– Speed
137 rpm
The Sulzer RTA62U-B engines with the following MCR rating:
– Power per cylinder
2285 kW
3110 bhp
– Speed
115 rpm
and
The Sulzer RTA72U-B engine with the following MCR rating:
– Power per cylinder
3080 kW
4190 bhp
– Speed
99 rpm
This issue of the Engine Selection and Project Manual (ESPM) is the first
edition for the above mentioned engine types.
Please note that the contents have been revised, which will have
consequences on new projects and could have an influence to your actual
projects. Particular attention is drawn to the major changes compared with
RTA52U, 62U and 72U engines:
a)
Three percent more power at R1, reduced rating layout field,
the lowest number of cylinders is 5.
b)
RTA62U-B and RTA72U-B are shorter than RTA62U and RTA72U.
c)
All three engine types are fully compatible to IMO-2000 regulations.
d)
The estimation of engine performance data (BSFC, BSEF and tEaT)
are given only for MCR rating. Derating and part load performance
figures can be obtained from the winGTD-program (CD-ROM included
inside the rear cover of this book).
e)
The inclusion of information referring to IMO-2000 regulations.
f)
The inclusion of information referring to winGTD (version 1.22,
mentioned under d) and EnSel (version 3.22), both on the CD-ROM
included inside the rear cover of this book.
A
Introduction
. . .
A–1
A1 Primary engine data . . . A–2
B
Considerations on engine selection
. . .
B–1
B1 Introduction . . . B–1 B2 Layout field . . . B–1 B2.1 Rating points R1, R2, R3 and R4. . . B–2 B2.2 Influence of propeller revolutions on the power requirement . . . B–2 B3 Load range. . . B–3 B3.1 Propeller curves . . . B–3 B3.2 Sea trial power . . . B–4 B3.3 Sea margin (SM). . . B–4 B3.4 Light running margin (LR) . . . B–4 B3.5 Engine margin (EM) or operational margin (OM) . . . B–4 B3.5.1 Continuous service rating (CSR =NOR=NCR). . . B–5 B3.5.2 Contract maximum continuous rating (CMCR = Rx) . . . B–5 B3.5.3 Engine optimisation point . . . B–5 B3.6 Load range limits . . . B–5 B3.7 Load range with main-engine driven generator . . . B–6 B3.8 Definitions . . . B–6 B3.9 Definition of light running margin . . . B–7 B4 Ambient temperature consideration. . . B–8 B4.1 Engine air inlet: operating temperatures from 45°C to 5°C. . . B–8 B4.2 Engine air inlet: arctic conditions at operating temperatures below 5°C. . . B–9
C
RTA52U-B, RTA62U-B and RTA72U-B engine
. . .
C–1
C1 RTA52U-B engine . . . C–1 C1.1 Engine description . . . C–1 C1.2 Engine data . . . C–3 C1.2.1 Reference conditions . . . C–3 C1.2.2 Design conditions . . . C–3 C1.2.3 Ancillary system design parameters . . . C–3 C1.2.4 Estimation of engine performance data . . . C–3 C1.2.4.1 Estimating brake specific fuel consumption (BSFC). . . C–4 C1.2.4.2 Estimating brake specific exhaust gas flow (BSEF) . . . C–5 C1.2.4.3 Estimating temperature of exhaust gas after turbocharger (tEaT) . . . C–6
C1.2.5.3 Hull vibration . . . C–7 C1.2.5.4 Estimation of engine vibration data . . . C–7 C1.2.5.5 Summary . . . C–11 C1.2.5.6 Questionnaire about engine vibration . . . C–12 C1.2.6 Turbocharger and scavenge air cooler . . . C–13 C1.2.6.1 Turbocharger and scavenge air cooler selection . . . C–14 C1.2.7 Auxiliary blower. . . C–17 C1.2.8 Turning gear requirements . . . C–17 C1.2.9 Pressure and temperature ranges . . . C–18 C1.3 Installation data. . . C–19 C1.3.1 Dimensions, masses and dismantling heights. . . C–19 C1.3.2 Engine outlines . . . C–20 C1.3.2.1 Engine outline 5RTA52U-B . . . C–20 C1.3.2.2 Engine outline 6RTA52U-B . . . C–21 C1.3.2.3 Engine outline 7RTA52U-B . . . C–22 C1.3.2.4 Engine outline 8RTA52U-B . . . C–23 C1.3.2.5 Engine seating . . . C–24 C1.4 Auxiliary power generation . . . C–25 C1.4.1 General information . . . C–25 C1.4.1.1 Introduction . . . C–25 C1.4.1.2 System description and layout . . . C–26 C1.4.2 Waste heat recovery . . . C–26 C1.4.3 Power take off (PTO) . . . C–26 C1.4.3.1 Arrangements of PTO . . . C–26 C1.4.3.2 PTO options. . . C–27 C1.4.3.3 Free-end PTO . . . C–27 C1.4.3.4 PTO Tunnel . . . C–27 C1.4.3.5 Constant-speed gear . . . C–27 C1.4.4 Sulzer S20U diesel generator set . . . C–28 C1.5 Ancillary systems . . . C–29 C1.5.1 General information . . . C–29 C1.5.1.1 Introduction . . . C–29 C1.5.1.2 Part-load data . . . C–29 C1.5.1.3 Engine system data . . . C–29 C1.5.2 Piping systems . . . C–33 C1.5.2.1 Cooling and pre-heating water systems . . . C–33 C1.5.2.2 Lubricating oil systems . . . C–37 C1.5.2.3 Fuel oil systems . . . C–42 C1.5.2.4 Starting and control air system. . . C–47 C1.5.2.5 Leakage collection system and washing devices . . . C–49 C1.5.3 Tank capacities . . . C–50 C1.5.4 Fire protection . . . C–51 C1.5.5 Exhaust gas system . . . C–52
C1.6 Engine noise . . . C–57 C1.6.1 Surface sound pressure level at 1 m distance under free field conditions . . . C–57 C1.6.2 Sound pressure level in suction pipe at turbocharger air inlet . . . C–57 C1.6.3 Sound pressure level in discharge pipe at turbocharger exhaust outlet . . . C–58 C2 RTA62U-B engine . . . C–59 C2.1 Engine description . . . C–59 C2.2 Engine data . . . C–61 C2.2.1 Reference conditions . . . C–61 C2.2.2 Design conditions . . . C–61 C2.2.3 Ancillary system design parameters . . . C–61 C2.2.4 Estimation of engine performance data . . . C–61 C2.2.4.1 Estimating brake specific fuel consumption (BSFC). . . C–62 C2.2.4.2 Estimating brake specific exhaust gas flow (BSEF) . . . C–63 C2.2.4.3 Estimating temperature of exhaust gas after turbocharger (tEaT) . . . C–64 C2.2.5 Vibration aspects . . . C–65 C2.2.5.1 Torsional vibration. . . C–65 C2.2.5.2 Axial vibration . . . C–65 C2.2.5.3 Hull vibration . . . C–65 C2.2.5.4 Estimation of engine vibration data . . . C–65 C2.2.5.5 Summary . . . C–69 C2.2.5.6 Questionnaire about engine vibration . . . C–70 C2.2.6 Turbocharger and scavenge air cooler . . . C–71 C2.2.6.1 Turbocharger and scavenge air cooler selection . . . C–72 C2.2.7 Auxiliary blower. . . C–75 C2.2.8 Turning gear requirements . . . C–75 C2.2.9 Pressure and temperature ranges . . . C–76 C2.3 Installation data. . . C–77 C2.3.1 Dimensions, masses and dismantling heights . . . C–77 C2.3.2 Engine outlines . . . C–78 C2.3.2.1 Engine outline 5RTA62U-B . . . C–78 C2.3.2.2 Engine outline 6RTA62U-B . . . C–79 C2.3.2.3 Engine outline 7RTA62U-B . . . C–80 C2.3.2.4 Engine outline 8RTA62U-B . . . C–81 C2.3.2.5 Engine seating . . . C–82 C2.4 Auxiliary power generation . . . C–83 C2.4.1 General information . . . C–83 C2.4.1.1 Introduction . . . C–83 C2.4.1.2 System description and layout . . . C–84 C2.4.2 Waste heat recovery . . . C–84 C2.4.3 Power take off (PTO) . . . C–84
C2.4.3.4 PTO Tunnel . . . C–85 C2.4.3.5 Constant-speed gear . . . C–85 C2.4.4 Sulzer S20U diesel generator set . . . C–86 C2.5 Ancillary systems . . . C–87 C2.5.1 General information . . . C–87 C2.5.1.1 Introduction . . . C–87 C2.5.1.2 Part-load data . . . C–87 C2.5.1.3 Engine system data . . . C–87 C2.5.2 Piping systems . . . C–91 C2.5.2.1 Cooling and pre-heating water systems . . . C–91 C2.5.2.2 Lubricating oil systems . . . C–95 C2.5.2.3 Fuel oil systems . . . C–100 C2.5.2.4 Starting and control air system. . . C–105 C2.5.2.5 Leakage collection system and washing devices . . . C–107 C2.5.3 Tank capacities . . . C–108 C2.5.4 Fire protection . . . C–109 C2.5.5 Exhaust gas system . . . C–110 C2.5.6 Engine air supply / Engine room ventilation . . . C–113 C2.6 Engine noise . . . C–115 C2.6.1 Surface sound pressure level at 1 m distance under free field conditions . . . C–115 C2.6.2 Sound pressure level in suction pipe at turbocharger air inlet . . . C–115 C2.6.3 Sound pressure level in discharge pipe at turbocharger exhaust outlet . . . C–116 C3 RTA72U-B engine . . . C–117 C3.1 Engine description . . . C–117 C3.2 Engine data . . . C–119 C3.2.1 Reference conditions . . . C–119 C3.2.2 Design conditions . . . C–119 C3.2.3 Ancillary system design parameters . . . C–119 C3.2.4 Estimation of engine performance data . . . C–119 C3.2.4.1 Estimating brake specific fuel consumption (BSFC). . . C–120 C3.2.4.2 Estimating brake specific exhaust gas flow (BSEF) . . . C–121 C3.2.4.3 Estimating temperature of exhaust gas after turbocharger (tEaT) . . . C–122 C3.2.5 Vibration aspects . . . C–123 C3.2.5.1 Torsional vibration. . . C–123 C3.2.5.2 Axial vibration . . . C–123 C3.2.5.3 Hull vibration . . . C–123 C3.2.5.4 Estimation of engine vibration data . . . C–123 C3.2.5.5 Summary . . . C–127 C3.2.5.6 Questionnaire about engine vibration . . . C–128 C3.2.6 Turbocharger and scavenge air cooler . . . C–129 C3.2.6.1 Turbocharger and scavenge air cooler selection . . . C–130 C3.2.7 Auxiliary blower. . . C–133
C3.2.9 Pressure and temperature ranges . . . C–134 C3.3 Installation data. . . C–135 C3.3.1 Dimensions, masses and dismantling heights . . . C–135 C3.3.2 Engine outlines . . . C–136 C3.3.2.1 Engine outline 5RTA72U-B . . . C–136 C3.3.2.2 Engine outline 6RTA72U-B . . . C–137 C3.3.2.3 Engine outline 7RTA72U-B . . . C–138 C3.3.2.4 Engine outline 8RTA72U-B . . . C–139 C3.3.2.5 Engine seating . . . C–140 C3.4 Auxiliary power generation . . . C–141 C3.4.1 General information . . . C–141 C3.4.1.1 Introduction . . . C–141 C3.4.1.2 System description and layout . . . C–142 C3.4.2 Waste heat recovery . . . C–142 C3.4.3 Power take off (PTO) . . . C–142 C3.4.3.1 Arrangements of PTO . . . C–142 C3.4.3.2 PTO options. . . C–143 C3.4.3.3 Free-end PTO . . . C–143 C3.4.3.4 PTO Tunnel . . . C–143 C3.4.3.5 Constant-speed gear . . . C–143 C3.4.4 Sulzer S20U diesel generator set . . . C–144 C3.5 Ancillary systems . . . C–145 C3.5.1 General information . . . C–145 C3.5.1.1 Introduction . . . C–145 C3.5.1.2 Part-load data . . . C–145 C3.5.1.3 Engine system data . . . C–145 C3.5.2 Piping systems . . . C–149 C3.5.2.1 Cooling and pre-heating water systems . . . C–149 C3.5.2.2 Lubricating oil systems . . . C–153 C3.5.2.3 Fuel oil systems . . . C–158 C3.5.2.4 Starting and control air system. . . C–163 C3.5.2.5 Leakage collection system and washing devices . . . C–165 C3.5.3 Tank capacities . . . C–166 C3.5.4 Fire protection . . . C–167 C3.5.5 Exhaust gas system . . . C–168 C3.5.6 Engine air supply / Engine room ventilation . . . C–171 C3.6 Engine noise . . . C–173 C3.6.1 Surface sound pressure level at 1 m distance under free field conditions . . . C–173 C3.6.2 Sound pressure level in suction pipe at turbocharger air inlet . . . C–173 C3.6.3 Sound pressure level in discharge pipe at turbocharger exhaust outlet . . . C–174
D
Engine management systems
. . .
D–1
D1 Introduction . . . D–1 D2 DENIS family . . . D–2 D2.1 DENIS specification . . . D–2 D2.2 Remote control systems suppliers. . . D–4 D2.3 Speed control . . . D–4 D2.3.1 Approved speed control (Governor) . . . D–4 D2.3.2 Selection of speed control. . . D–5 D2.3.3 Technical assistance . . . D–5 D2.4 Alarm sensors . . . D–5 D3 MAPEX Family . . . D–8 D3.1 SIPWA-TP: Trend processing. . . D–9 D3.2 MAPEX-PR: Piston-running reliability . . . D–10 D3.3 MAPEX-SM . . . D–11
E
Engine emissions
. . .
E–1
E1 IMO-2000 regulations . . . E–1 E1.1 IMO . . . E–1 E1.2 Establishment of emission limits for ships . . . E–1 E1.3 Regulation regarding NOx emissions of diesel engines . . . E–1 E1.4 Date of application of ANNEX VI . . . E–1 E1.5 Procedure for certification of engines . . . E–2
E2 Measures for compliance with the IMO regulation of the RTA52U-B, RTA62U-B and
RTA72U-B engines. . . E–2 E2.1 Standard measures . . . E–2 E2.2 Extended measures . . . E–2
F
winGTD – General Technical Data
. . .
F–1
F1 Installation of winGTD . . . F–1 F1.1 System requirements . . . F–1 F1.2 Installing winGTD . . . F–1 F1.3 Changes to previous versions . . . F–1 F2 Using winGTD (RTA52U-B, RTA62U-B and RTA72U-B) . . . F–2
F2.1 Main window . . . F–2 F2.2 Two-stroke propulsion engines. . . F–2 F2.3 Cooling system . . . F–2 F2.4 Lubricating oil system . . . F–3 F2.5 Results of the computation . . . F–3 F2.5.1 Service conditions . . . F–4 F2.6 Saving a project . . . F–4
G
Appendix
. . .
G–1
G1 Reference to other Wärtsilä NSD Switzerland documentation . . . G–1 G2 Piping symbols . . . G–2 G3 SI dimensions for internal combustion engines . . . G–5 G4 Approximate conversion factors . . . G–6 G5 Wärtsilä NSD Corporation worldwide . . . G–7 G5.1 Headquarters. . . G–7 G5.2 Marine business . . . G–7 G5.3 Navy business . . . G–7 G5.4 Product companies. . . G–7 G5.5 Corporation network . . . G–8 G5.6 Licensees . . . G–14 G6 Questionnaire order specification for RTA52, 62 and 72U-B engines . . . G–19
Fig. A1 Power/speed range of all IMO-2000 regulation compatible RTA engines. . . A–1 Fig. B1 Layout field applicable to the RTA engines. . . B–1 Fig. B2 Load range, with the load diagram of an engine . . . B–3
Fig. B3 Load range diagram for a specific engine showing the corresponding power
and speed margins. . . B–4
Fig. B4 Load range diagram for an engine equipped with a main-engine driven generator,
whether it is a shaft generator or a PTO-driven generator . . . B–6 Fig. B5 Scavenge air system for arctic conditions . . . B–9 Fig. B6 Blow-off effect at arctic conditions . . . B–9 RTA52U-B engine figures
Fig. C1 Sulzer RTA52U-B cross section. . . C–1 Fig. C2 Estimation of BSFC for Rx . . . C–4 Fig. C3 Estimation of BSEF for Rx . . . C–5 Fig. C4 Estimation of tEaT for Rx . . . C–6 Fig. C5 External couples and forces . . . C–8 Fig. C6 Typical attachment points for lateral stays . . . C–9 Fig. C7 ‘H-type’ and ‘X-type’ modes of engine vibration . . . C–10
Fig. C8 Turbocharger and scavenge air cooler selection (ABB VTR type tubochargers) . . C–14
Fig. C9 Turbocharger and scavenge air cooler selection (MHI MET type tubochargers) . . C–15
Fig. C10 Turbocharger and scavenge air cooler selection (MAN NA type tubochargers) . . . C–16
Fig. C11 Engine dimensions . . . C–19 Fig. C12 5RTA52U-B engine outline . . . C–20 Fig. C13 6RTA52U-B engine outline . . . C–21 Fig. C14 7RTA52U-B engine outline . . . C–22 Fig. C15 8RTA52U-B engine outline . . . C–23 Fig. C16 Engine foundation for RTA52U-B engine seating with epoxy resin chocks . . . C–24 Fig. C17 Heat recovery system layout . . . C–25 Fig. C18 Free-end PTO gear . . . C–26 Fig. C19 Tunnel PTO gear . . . C–26 Fig. C20 Key to illustrations . . . C–26 Fig. C21 Sulzer S20U diesel generator set . . . C–28 Fig. C22 Conventional sea-water cooling system . . . C–31 Fig. C23 Central fresh water cooling system, single-stage SAC . . . C–32 Fig. C24 Conventional sea-water cooling system layout . . . C–33 Fig. C25 Central fresh water cooling layout for single-stage scavenge air cooler . . . C–34 Fig. C26 Cylinder cooling water system . . . C–35 Fig. C27 Engine pre-heating power . . . C–36 Fig. C28 Main lubricating oil system . . . C–39 Fig. C29 Cylinder lubricating oil system . . . C–40 Fig. C30 Fuel oil viscosity-temperature diagram . . . C–43 Fig. C31 Heavy fuel oil treatment layout . . . C–45 Fig. C32 Pressurized fuel oil system . . . C–46 Fig. C33 Starting and control air system. . . C–47
Fig. C35 Leakage collection and washing layout.
Typical arrangement of wash water supply and drains collection . . . C–49 Fig. C36 Determination of exhaust pipe diameters . . . C–52 Fig. C37 Estimation of exhaust gas density . . . C–53 Fig. C38 Estimation of exhaust pipe diameters . . . C–53 Fig. C39 Air filter size . . . C–56 Fig. C40 Sound pressure level at 1 m distance . . . C–57 Fig. C41 Sound pressure level at turbocharger air inlet . . . C–57 Fig. C42 Sound pressure level at turbocharger exhaust outlet . . . C–58 RTA62U-B engine figures
Fig. C43 Sulzer RTA62U-B cross section . . . C–59 Fig. C44 Estimation of BSFC for Rx . . . C–62 Fig. C45 Estimation of BSEF for Rx . . . C–63 Fig. C46 Estimation of tEaT for Rx . . . C–64 Fig. C47 External couples and forces . . . C–66 Fig. C48 Typical attachment points for lateral stays . . . C–67 Fig. C49 ‘H-type’ and ‘X-type’ modes of engine vibration . . . C–68
Fig. C50 Turbocharger and scavenge air cooler selection (ABB VTR type tubochargers) . . C–72
Fig. C51 Turbocharger and scavenge air cooler selection (MHI MET type tubochargers) . . C–73
Fig. C52 Turbocharger and scavenge air selection (MAN NA type tubochargers) . . . C–74 Fig. C53 Engine dimensions . . . C–77 Fig. C54 5RTA62U-B engine outline . . . C–78 Fig. C55 6RTA62U-B engine outline . . . C–79 Fig. C56 7RTA62U-B engine outline . . . C–80 Fig. C57 8RTA62U-B engine outline . . . C–81 Fig. C58 Engine foundation for RTA62U-B engine seating with epoxy resin chocks . . . C–82 Fig. C59 Heat recovery system layout . . . C–83 Fig. C60 Free-end PTO gear . . . C–84 Fig. C61 Tunnel PTO gear . . . C–84 Fig. C62 Key to illustrations . . . C–84 Fig. C63 Sulzer S20U diesel generator set . . . C–86 Fig. C64 Conventional sea-water cooling system . . . C–89 Fig. C65 Central fresh water cooling system, single-stage SAC . . . C–90 Fig. C66 Conventional sea-water cooling system layout . . . C–91 Fig. C67 Central fresh water cooling layout for single-stage scavenge air cooler . . . C–92 Fig. C68 Cylinder cooling water system . . . C–93 Fig. C69 Engine pre-heating power . . . C–94 Fig. C70 Main lubricating oil system . . . C–97 Fig. C71 Cylinder lubricating oil system . . . C–98 Fig. C72 Fuel oil viscosity-temperature diagram . . . C–101 Fig. C73 Heavy fuel oil treatment layout . . . C–103 Fig. C74 Pressurized fuel oil system . . . C–104
Fig. C77 Leakage collection and washing layout.
Typical arrangement of wash water supply and drains collection . . . C–107 Fig. C78 Determination of exhaust pipe diameters . . . C–110 Fig. C79 Estimation of exhaust gas density . . . C–111 Fig. C80 Estimation of exhaust pipe diameters . . . C–111 Fig. C81 Air filter size . . . C–114 Fig. C82 Sound pressure level at 1 m distance. . . C–115 Fig. C83 Sound pressure level at turbocharger air inlet. . . C–115 Fig. C84 Sound pressure level at turbocharger exhaust outlet . . . C–116 RTA72U-B engine figures
Fig. C85 Sulzer RTA72U-B cross section. . . C–117 Fig. C86 Estimation of BSFC for Rx . . . C–120 Fig. C87 Estimation of BSEF for Rx . . . C–121 Fig. C88 Estimation of tEaT for Rx . . . C–122 Fig. C89 External couples and forces . . . C–124 Fig. C90 Typical attachment points for lateral stays . . . C–125 Fig. C91 ‘H-type’ and ‘X-type’ modes of engine vibration . . . C–126
Fig. C92 Turbocharger and scavenge air cooler selection (ABB VTR type turbochargers) . . C–130
Fig. C93 Turbocharger and scavenge air cooler selection (MHI MET type tubochargers) . . C–131
Fig. C94 Turbocharger and scavenge air cooler selection (MAN NA type tubochargers) . . . C–132
Fig. C95 Engine dimensions . . . C–135 Fig. C96 5RTA72U-B engine outline . . . C–136 Fig. C97 6RTA72U-B engine outline . . . C–137 Fig. C98 7RTA72U-B engine outline . . . C–138 Fig. C99 8RTA72U-B engine outline . . . C–139 Fig. C100 Engine foundation for RTA72U-B engine seating with epoxy resin chocks . . . C–140 Fig. C101 Heat recovery system layout . . . C–141 Fig. C102 Free-end PTO gear . . . C–142 Fig. C103 Tunnel PTO gear . . . C–142 Fig. C104 Key to illustrations . . . C–142 Fig. C105 Sulzer S20U diesel generator set . . . C–144 Fig. C106 Conventional sea-water cooling system . . . C–147 Fig. C107 Central fresh water cooling system, single-stage SAC . . . C–148 Fig. C108 Conventional sea-water cooling system . . . C–149 Fig. C109 Central fresh water cooling layout for single-stage scavenge air cooler . . . C–150 Fig. C110 Cylinder cooling water system . . . C–151 Fig. C111 Engine pre-heating power . . . C–152 Fig. C112 Main lubricating oil system . . . C–155 Fig. C113 Cylinder lubricating oil system . . . C–156 Fig. C114 Fuel oil viscosity-temperature diagram . . . C–159 Fig. C115 Heavy fuel oil treatment layout . . . C–161 Fig. C116 Pressurized fuel oil system . . . C–162 Fig. C117 Starting and control air system. . . C–163 Fig. C118 Correction of air receiver and air compressor capacities. . . C–164
Fig. C119 Leakage collection and washing layout.
Typical arrangement of wash water supply and drains collection . . . C–165 Fig. C120 Determination of exhaust pipe diameters . . . C–168 Fig. C121 Estimation of exhaust gas density . . . C–169 Fig. C122 Estimation of exhaust pipe diameters . . . C–169 Fig. C123 Air filter size . . . C–172 Fig. C124 Sound pressure level at 1 m distance . . . C–173 Fig. C125 Sound pressure level at turbocharger air inlet . . . C–173 Fig. C126 Sound pressure level at turbocharger exhaust outlet . . . C–174
Fig. D1 Intelligent engine-management comprising DENIS and MAPEX modules . . . D–1
Fig. D2 DENIS-6 remote control . . . D–3 Fig. D3 SIPWA-TP . . . D–9 Fig. D4 MAPEX-PR . . . D–10 Fig. D5 MAPEX- communication . . . D–11 Fig. D6 The maintenance circle . . . D–12 Fig. E1 Speed dependent maximum average NOx emissions by engines. . . E–1 Fig. E2 RTA52U-B compliance with the IMO regulation . . . E–2 Fig. E3 RTA62U-B compliance with the IMO regulation . . . E–2 Fig. E4 RTA72U-B compliance with the IMO regulation . . . E–2 Fig. F1 winGTD: Main window . . . F–2 Fig. F2 winGTD: Two-stroke engine propulsion . . . F–2 Fig. F3 winGTD: Lubricating oil system layout . . . F–3 Fig. F4 winGTD: Show results of the computation . . . F–3 Fig. F5 winGTD: Choose Service conditions . . . F–4 Fig. F6 winGTD: Service conditions . . . F–4 Fig. F7 winGTD: Save as... . . F–4 Fig. G1 Piping symbols 1. . . G–2 Fig. G2 Piping symbols 2. . . G–3 Fig. G3 Piping symbols 3. . . G–4
Table A1 Primary engine data of Sulzer RTA52U-B, RTA62U-B and RTA72U-B. . . A–2 RTA52U-B engine data tables
Table C1 Free couples of mass forces and torque variations . . . C–8 Table C2 Guide forces and moments. . . C–10 Table C3 Countermeasures for dynamic effects . . . C–11 Table C4 Scavenge air cooler details. . . C–13 Table C5 Turbocharger details . . . C–13 Table C6 Auxiliary blower requirements . . . C–17 Table C7 Approximative turning gear requirements . . . C–17 Table C8 Pressure and temperature ranges . . . C–18 Table C9 Dimensions and masses . . . C–19 Table C10 PTO feasibility . . . C–26 Table C11 PTO options for power and speed . . . C–27 Table C12 Engine data for Sulzer S20U . . . C–28 Table C13 R1 data for conventional sea-water cooling system for engines
with ABB VTR turbochargers.. . . C–31 Table C14 R1 data for central fresh water cooling system for engines with
ABB VTR turbochargers, single-stage SAC. . . C–32 Table C15 Lubricating oils . . . C–41 Table C16 Fuel oil requirements . . . C–42 Table C17 Air receiver and air compressor capacities . . . C–48 Table C18 Tank capacities . . . C–50 Table C19 Recommended quantities of fire extinguishing medium . . . C–51 Table C20 Guidance for air filtration . . . C–55 RTA62U-B engine data tables
Table C21 Free couples of mass forces and torque variations . . . C–66 Table C22 Guide forces and moments. . . C–68 Table C23 Countermeasures for dynamic effects . . . C–69 Table C24 Scavenge air cooler details. . . C–71 Table C25 Turbocharger details . . . C–71 Table C26 Auxiliary blower requirements . . . C–75 Table C27 Approximative turning gear requirements . . . C–75 Table C28 Pressure and temperature ranges . . . C–76 Table C29 Dimensions and masses . . . C–77 Table C30 PTO feasibility . . . C–84 Table C31 PTO options for power and speed . . . C–85 Table C32 Engine data for Sulzer S20U . . . C–86 Table C33 R1 data for conventional sea-water cooling system for engines
with ABB VTR turbochargers.. . . C–89 Table C34 R1 data for central fresh water cooling system for engines with
ABB VTR turbochargers, single-stage SAC. . . C–90 Table C35 Lubricating oils . . . C–99 Table C36 Fuel oil requirements . . . C–100
Table C38 Tank capacities . . . C–108 Table C39 Recommended quantities of fire extinguishing medium . . . C–109 Table C40 Guidance for air filtration . . . C–113 RTA72U-B engine data tables
Table C41 Free couples of mass forces and torque variations . . . C–124 Table C42 Guide forces and moments . . . C–126 Table C43 Countermeasures for dynamic effects . . . C–127 Table C44 Scavenge air cooler details . . . C–129 Table C45 Turbocharger details . . . C–129 Table C46 Auxiliary blower requirements . . . C–133 Table C47 Approximative turning gear requirements . . . C–133 Table C48 Pressure and temperature ranges . . . C–134 Table C49 Dimensions and masses . . . C–135 Table C50 PTO feasibility . . . C–142 Table C51 PTO options for power and speed . . . C–143 Table C52 Engine data for Sulzer S20U . . . C–144 Table C53 R1 data for conventional sea-water cooling system for engines
with ABB VTR turbochargers.. . . C–147 Table C54 R1 data for central fresh water cooling system for engines with
ABB VTR turbochargers, single-stage SAC. . . C–148 Table C55 Lubricating oils . . . C–157 Table C56 Fuel oil requirements . . . C–158 Table C57 Air receiver and air compressor capacities . . . C–164 Table C58 Tank capacities . . . C–166 Table C59 Recommended quantities of fire extinguishing medium . . . C–167 Table C60 Guidance for air filtration . . . C–171 Table D1 DENIS specification . . . D–3 Table D2 Alarm and safety functions of RTA.2U-B marine diesel engines . . . D–6 Table D3 Alarm and safety functions of RTA.2U-B marine diesel engines . . . D–7 Table G1 SI dimensions . . . G–5 Table G2 Questionnaire 1. . . G–20 Table G3 Questionnaire 2. . . G–21 Table G4 Questionnaire 3. . . G–22 Table G5 Questionnaire 4. . . G–23 Table G6 Questionnaire 5. . . G–24 Table G7 Questionnaire 6. . . G–25 Table G8 Questionnaire 7. . . G–26 Table G9 Questionnaire 8. . . G–27 Table G10 Questionnaire 9. . . G–28 Table G11 Questionnaire 10 . . . G–29
Table G12 Questionnaire 11. . . G–30 Table G13 Questionnaire 12 . . . G–31 Table G14 Questionnaire 13 . . . G–32 Table G15 Questionnaire 14 . . . G–33
ABB ASEA Brown Boveri
ALM Alarm
AMS Attended machinery space
BFO Bunker fuel oil
BN Base Number
BSEF Brake specific exhaust gas flow
BSFC Brake specific fuel consumption
CAC Charge air cooler (four stroke)
CCR Conradson carbon
CCW Cylinder cooling water
CMCR Contract maximum continuous rating (Rx)
cSt centi-Stoke (kinematic viscosity)
CSR Continuous service rating (also
designated NOR and NCR)
DENIS Diesel engine control and optimizing
specification
e.g. Exampli gratia (for example, for
instance)
EM Engine margin
EnSelR Engine selection program
ESPM Engine selection and project manual
FQS Fuel quality setting
FW Fresh water
GEA Scavenge / charge air cooler
(GEA manufacture)
GTD General technical data book
HFO Heavy fuel oil
HT High temperature
i.e. id est (that is to say)
IMO International Maritime Organisation
IND Indication
IPDLC Integrated power-dependent liner
cooling
ISO International Standard Organisation
kW Kilowatt
kWe Kilowatt electrical
kWh Kilowatt hour
LCV Lower calorific value
LR Light running margin
LT Low temperature
M Torque
MAPEX Monitoring and maintenance performance
enhancement with expert knowledge
M1H External couple 1st order horizontal
M1V External couple 1st order vertical
M2V External couple 2nd order vertical
MCR Maximum continuous rating (R1)
MDO Marine diesel oil
mep Mean effective pressure
MET Turbocharger (Mitsubishi manufacture)
MHI Mitsubishi
MIM Marine installation manual
N, n Speed of rotation
NCR Nominal continuous rating
NOR Nominal operation rating
OM Operational margin
P Power
PI Pressure indicator
PIG Proportional integral governor
ppm Parts per million
PTO Power take off
RCS Remote control system
RW1 Redwood seconds No. 1 (kinematic
viscosity)
SAC Scavenge air cooler (two stroke)
SAE Society of Automotive Engineers
S/G Shaft generator
SHD Shut down
SIPWA-TP Sulzer integrated piston ring wear detecting arrangement with trend processing
SLD Slow down
SM Sea margin
SSU Saybolt second universal
SW Sea-water
TBO Time between overhauls
TC Turbocharger
tEat Temperature of exhaust gas after
turbine
UMS Unattended machinery space
VEC Variable exhaust valve closing
VI Viscosity index
VIT Variable injection timing
VTR Turbocharger (ABB manufacture)
WG Water gauge
The Sulzer RTA52U-B, RTA62U-B and RTA72U-B low-speed diesel engines are a further development of the RTA52-U, RTA62-U and RTA72-U engines. They are designed for today’s and future large and fast general cargo ships, container ships, tanker and bulk carrier vessels and are available with any or all of the following options:
1. Main-engine driven generator –
Power take off (PTO);
2. Conventional sea-water or central fresh water cooling systems;
3. ABB, Mitsubishi or MAN turbochargers;
4. Engine monitoring and remote control.
The purpose of this manual is to provide our clients with information enabling them to select the engine and options to meet the needs of their vessels.
F10.3873
Fig. A1 Power/speed range of all IMO-2000 regulation compatible RTA engines
This book is intended to provide the information required for the layout of marine propulsion plants. Its content is subject to the understanding that any data and information herein have been prepared with care and to the best of our knowledge. We do not, however, assume any liability with regard to unforeseen variations in accuracy thereof or for any consequences arising therefrom.
Wärtsilä NSD Switzerland Ltd PO Box 414
CH-8401 Winterthur, Switzerland Telephone: +41 52 262 4922 Telefax: +41 52 212 4917
A1
Primary engine data
Engine RTA52U-B RTA62U-B RTA72U-B
Bore x stroke [mm] 520 x 1800 620 x 2150 720 x 2500 Speed [rpm] 137 137 110 110 115 115 92 92 99 99 79 79 Engine power (MCR) Cylin-der Power R1 R2 R3 R4 R1 R2 R3 R4 R1 R2 R3 R4 5 [bhp][kW] 10 8758 000 5 6007 625 6 4258 750 5 6007 625 15 55011 425 10 8758 000 12 4509 150 10 8758 000 15 40020 950 10 77514 650 12 30016 725 10 77514 650 6 [kW] [bhp] 9 600 13 050 6 720 9 150 7 710 10 500 6 720 9 150 13 710 18 660 9 600 13 050 10 980 14 940 9 600 13 050 18 480 25 140 12 930 17 580 14 760 20 070 12 930 17 580 7 [kW] [bhp] 11 200 15 225 7 840 10 675 8 995 12 250 7 840 10 675 15 995 21 770 11 200 15 225 12 810 17 430 11 200 15 225 21 560 29 330 15 085 20 510 17 220 23 415 15 085 20 510 8 [kW] [bhp] 12 800 17 400 8 960 12 200 10 280 14 000 8 960 12 200 18 280 24 880 12 800 17 400 14 640 19 920 12 800 17 400 24 640 33 520 17 240 23 440 19 680 26 760 17 240 23 440
Brake specific fuel consumption (BSFC) Load 85 % [g/bhph][g/kWh] 171126 168124 171126 169124 170125 167123 170125 168123 168124 165121 168124 166122 100 % [g/kWh] [g/bhph] 174 128 168 124 174 128 170 125 173 127 167 123 173 127 169 124 171 126 165 121 171 126 167 123 mep [bar] 18.3 12.8 18.3 16.0 18.4 12.9 18.4 16.1 18.3 12.8 18.4 16.1
Lubricating oil consumption *1)
System oil approximately 6 kg/cyl per day approximately 7 kg/cyl per day approximately 9 kg/cyl per day
Cylinder oil *2) 0.9–1.3 g/kWh
Remark: *1) For fully run-in engines and under normal operating conditions.
*2) This data is for guidance only, it may have to be increased as the actual cylinder lubricating oil consumption in service is dependent on a number of operational factors.
B1
Introduction
Selection of a suitable main engine to meet the power demands of a given project involves proper tuning in respect of load range and the influence of operating conditions which are likely to prevail throughout the entire life of the ship. This chapter explains the main principles in selecting a Sulzer RTA low-speed diesel engine.
Every engine has a layout field within which the power/speed ratio (= rating) can be selected. It is limited by envelopes defining the area where 100 per cent firing pressure (i.e. nominal maximum pressure) is available for the selection of the contract maximum continuous rating (CMCR). Contrary to the ‘layout field’, the ‘load range’ is the admissible area of operation once the CMCR has been determined.
In order to define the required contract maximum continuous rating, various parameters such as propulsive power, propeller efficiency, operational flexibility, power and speed margins, possibility of a main-engine driven generator, and the ship’s trading patterns need to be considered.
Selecting the most suitable engine is vital to achieving an efficient cost/benefit response to a specific transport requirement.
B2
Layout field
The layout field shown in figure B1 is the area of power and engine speed within which the contract maximum continuous rating of an engine can be positioned individually to give the desired combination of propulsive power and rotational speed. Engines within this layout field will be tuned for maximum firing pressure and best fuel efficiency. Experience over the last years has shown that engines are ordered with CMCR points in the upper part of the layout field only. It was
order to provide the most cost effective solution for the projected application. Please note that the layout fields for some RTA engines have been reduced in the lower parts of the former layout fields in order to allow the fulfilling of IMO-2000 emission regulations. This is of no disadvantage since engine ratings are normally selected near the R1–R3 line
F10.3875
Fig. B1 Layout field applicable to the RTA engines. The contracted maximum continuous rating (Rx) may be freely positioned within the layout field for that engine.
The engine speed is given on the horizontal axis and the engine power on the vertical axis of the layout field, both are expressed as a percentage (%) of the respective engine’s nominal
Percentage values are being used so that the same diagram can be applied to various engine models. The scales are logarithmic so that exponential curves, such as propeller characteristics (cubic power) and mean effective pressure (mep) curves (first power), are straight lines.
The layout field serves to determine the specific fuel oil consumption, exhaust gas flow and temperature, fuel injection parameters, turbo-charger and scavenge air cooler specifications for a given engine.
Calculations for specific fuel consumption, exhaust gas flows and temperature after turbine are explained in later chapters.
B2.1
Rating points R1, R2, R3 and R4
The rating points for the RTA engines R1, R2, R3 and R4 are the corner points of the engine layout field.
The points R1 represent the nominal maximum continuous rating (MCR). It is the maximum power/speed combination which is available for a particular engine. 10 per cent overload thereof is permissible for one hour during sea trials in the presence of authorized representatives of the engine builder.
The points R2 define 100 per cent speed and 70 per cent power.
The points R3 define 80 per cent speed and 80 per cent power.
The connection R1 – R3 is the nominal 100 per cent line of constant mean effective pressure.
The points R4 define 80 per cent speed and 70 per cent power.
The connection line R2 – R4 is the line of 70 per cent power between 80 and 100 per cent speed.
Points such as Rx are power/speed ratios for the selection of contracted maximum continuous ratings required for individual applications. Rating points Rx can be selected within the entire layout field for that particular engine.
B2.2
Influence of propeller revolutions
on the power requirement
At constant ship speed and for a given propeller type, lower propeller revolutions combined with a larger propeller diameter increase the total propulsive efficiency. Less power is needed to propel the vessel at a given speed.
The relative change of required power in function of the propeller revolutions can be approximated by the following relation:
Px2ńPx1+ǒN2ńN1Ǔa
Pxj = Propulsive power at propeller revolution Nj
Nj = Propeller speed corresponding with propulsive power Pxj
α = 0.15 for tankers and general cargo ships up to 10 000 dwt.
= 0.20 for tankers, bulkcarriers from 10 000 dwt to 30 000 dwt.
= 0.25 for tankers, bulkcarriers larger than 30 000 dwt.
= 0.17 for reefers and container ships up to 3000 TEU.
= 0.22 for container ships larger than 3000 TEU.
This relation is used in the engine selection procedure to compare different engine alternatives and to select optimum propeller revolutions within the selected engine layout field.
Usually, the selected propeller revolution depends on the maximum permissible propeller diameter. The maximum propeller diameter is often determined by operational requirements such as design draught and ballast draught limitations, class recommendations concerning propeller – hull clearance (pressure impulse induced by the propeller on the hull).
The selection of main engine in combination with the optimum propeller (efficiency) is an iterative procedure where also commercial considerations (engine and propeller prices) play a great role. From the above follows that, when a power/speed combination is known to be required, for example point Rx1 as shown in figure B1, a CMCR line for a given ship’s speed, following the above approximation, can be drawn through the point Rx1. This is a straight line with a slope α, shown as
a dashed line, i.e. through Rx2 in figure B1. Any other point on this line represents a new power/speed combination, requiring a new adaptation of the propeller.
F10.1863
.
* See also under B3.2
Fig. B2 Load range, with the load diagram of an engine corresponding to a specific rating point Rx
B3
Load range
The load range diagram shown in figure B2 defines the power/speed limits for the operation of the engine. For simplicity and general application to all engine models, the scales for power and speed are logarithmic and given in percentage values of the CMCR (Rx) point. In practice absolute figures might be used for a specific installation project.
B3.1
Propeller curves
In order to establish the proper location of propeller curves, it is necessary to know the ship’s speed to power response.
Propeller curve without sea margin is for a ship with a new and clean hull in calm water and weather, often referred to as ‘trial condition’.
The propeller curves can be determined by using full scale trial results of similar ships, algorithms developed by maritime research institutes or model tank results. Furthermore, it is necessary to define the maximum reasonable diameter of the propeller which can be fitted to the ship. With this information at hand and by applying propeller series such as the ‘Wageningen’, ‘SSPA’ (Swedish Maritime Research Association), ‘MAU’ (Modified AU), etc., the power/speed relationships can be established and characteristics developed. The relation between absorbed power and rotational speed for a fixed-pitch propeller can be approximated by the following cubic relationship:
P2ńP1+ǒN2ńN1Ǔ 3
in which
Pi = propeller power
Ni = propeller speed
Propeller curve without sea margin is often called the light running curve. The nominal propeller characteristic is a cubic curve through the CMCR
B3.2
Sea trial power
The sea trial power must be specified. Figure B2 shows the sea trial power to be the power required for point ‘B’ on the propeller curve. Often and alternatively the power required for point ‘A’ on the propeller curve is referred to as the sea trial power.
B3.3
Sea margin (SM)
The increase in required power to maintain a given ship’s speed in calm weather (point ‘A’ in figure B2) and under average service condition (point ‘D’), is defined as the ‘sea margin’. This margin can vary depending on owner’s and charterer’s expectations, routes, season and schedules of the ship. The location of the reference point ‘A’ and the magnitude of the sea margin are determined between the shipbuilder and the owner. They form part of the newbuilding contract.
With the help of effective antifouling paints, drydocking intervals have been prolonged up to 4 or 5 years. Therefore, it is still realistic to provide an average sea margin of about 15 per cent of the sea trial power, refer to figure B2 , unless as mentioned above, the actual ship type and service route dictate otherwise.
B3.4
Light running margin (LR)
The sea trial performance (curve ‘a’) in figure B3 should allow for a 3 to 7 per cent light running of the propeller when compared to the nominal pro-peller characteristic (the example in figure B3 shows 5 per cent light running margin only). This is in order to provide a sufficient torque reserve whenever full power must be attained under un-favourable conditions. Normally, the propeller is hydrodynamically optimized for a point ‘B’. The trial speed found for ‘A’ is equal to the service speed at ‘D’ stipulated in the contract at 90 per cent of CMCR.
The recommended light running margin originates from past experience. It varies with specific ship designs, speeds, drydocking intervals, and trade
routes (for additional information, refer to the ‘Definition of light running margin’ B3.9).
F10.3148
Fig. B3 Load range diagram for a specific engine showing the corresponding power and speed margins
B3.5
Engine margin (EM) or operational
margin (OM)
Most owners specify the contractual ship’s loaded service speed at 85 to 90 per cent of the contract maximum continuous rating. The remaining 10 to 15 per cent power can then be utilized to catch up with delays in schedule or for the timing of drydocking intervals. This margin is usually deducted from the CMCR. Therefore, the 100 per cent power line is found by dividing the power at point ‘D’ by 0.85 to 0.90. The graphic approach to find the level of CMCR is illustrated in figures B2, B3 and B4.
In the examples two current methods are shown. Figure B2 presents the method of fixing point ‘B’ and CMCR at 100 per cent speed thus obtaining automatically a light running margin B– D of 3.5 per cent. Figures B3 and B4 show the method
of plotting the light running margin from point ‘B’ to point ‘D’ or ‘Di’ (in our example 5 per cent) and then along the nominal propeller characteristic to obtain the CMCR point. In the examples point ‘B’ was chosen to be at 90 per cent engine power.
B3.5.1
Continuous service rating
(CSR=NOR=NCR)
Point ‘A’ represents power and speed of a ship operating at contractual speed in calm seas with a new clean hull and propeller. On the other hand, the same ship at the same speed requires a power/speed combination according to point ‘D’, shown in figure B2, B3 and B4, under service condition with aged hull and average weather. ‘D’ is then the CSR point.
B3.5.2
Contract maximum continuous
rating (CMCR = Rx)
By dividing CSR by 0.90 (in our example), an operational margin of 10 per cent is provided, see figures B2 and B3. The found point Rx, also designated as CMCR, can be selected freely within the layout field defined by the four corner points R1, R2, R3 and R4 (see figure B1).
B3.5.3
Engine optimisation point
The RTA52U-B, RTA62U-B and RTA72U-B engines are optimized for the selected CMCR point. The built-in variable injection timing (VIT) feature provides lowest fuel consumptions at part load. Other optimisation points than at CMCR are not regarded to be of advantage for these engines.
B3.6
Load range limits
Once an engine is optimized at CMCR (Rx), the working range of the engine is limited by the following border lines, refer to figure B2:
Line 1 is a constant mep line through CMCR from 100 per cent speed and power down to
Line 2 is the overload limit. It is a constant mep line reaching from 100 per cent power and 93.8 per cent speed to 110 per cent power and 103.2 per cent speed. The latter is the point of intersection between the nominal propeller characteristic and 110 per cent power.
Line 3 is the 104 per cent speed limit. For speed derated engines (NCMCR≤0.98NMCR) this limit can be extended to 106 per cent if tor-sional vibration limitations are not ex-ceeded.
Line 4 is the overspeed limit at 108 per cent
speed. The overspeed range between 104 and 108 per cent speed is only per-missible during sea trials if needed to demonstrate the ship’s speed at CMCR power with a light running propeller in the presence of authorized representatives of the engine builder.
Line 5 reaches from 95 per cent power and
speed to 45 per cent power and 70 per cent speed. This represents a curve de-fined by the equation:
P2ńP1+ǒN2ńN1Ǔ2.45
When approaching line 5 , the engine will
increasingly suffer from lack of scavenge air and its consequences. The area formed by lines 1 , 3 and 5 represents the range within which the engine should be operated. More specifically, the area which is limited by the nominal propeller characteristic, 100 per cent power and line
3 is recommended for continuous opera-tion. The area between the nominal pro-peller characteristic (figures B2, B3 and B4) and line 5 should be reserved for ac-celeration, shallow water and normal op-erational flexibility.
Line 6 is defined by the equation:
P2ńP1+ǒN2ńN1Ǔ 2.45
through 100 per cent power and 93.8 per cent speed.
The area above line 1 is the overload
range. It is only allowed to operate en-gines in that range for a maximum dura-tion of one hour during sea trials in the presence of authorized representatives of the engine builder.
The area between lines 5 and 6 and
constant torque should only be used for transient conditions, i.e. during fast accel-eration. This range is called ‘service range with operational time limit’. As al-ready stated above, the area between the nominal propeller characteristic and line
5 is not an ideal zone for continuous op-eration of the engine.
B3.7
Load range with main-engine
driven generator
The load range diagram with main-engine driven generator, whether it is a shaft generator (S/G) mounted on the intermediate shaft or driven through a power take off gear (PTO), is very similar to that in figure B3. The difference is the additional power for the PTO, shown by curve ‘c’ in figure B4. This curve is not parallel to the propeller characteristic without main-engine driven generator because of the varying magnitude of a constant power in a logarithmic scale. In the example of figure B4, the main-engine driven generator is assumed to absorb 5 per cent of the nominal engine power.
Of course, the CMCR point thus found must also lie within the layout field of the engine as shown in figure B1.
F10.3149
Fig. B4 Load range diagram for an engine equipped with a main-engine driven generator, whether it is a shaft generator or a PTO-driven generator
B3.8
Definitions
Engine layout field:
Power/speed field within which the CMCR of an engine may be freely positioned. The four corner points of the engine layout field are R1, R2, R3 and R4 (refer also to B2).
Engine load range:
Admissible power/speed area of operation based on the CMCR point (see also B2).
B3.9
Definition of light running margin
The recommended ‘light running’ of a propeller under new hull, loaded sea trial condition, is to compensate for the expected future drop in revolutions for constant-power operation. The range is between 3–7 % of CMCR engine speed. Example: Under the following assumptions a light running margin of 5–6 % is required as follow:
• Drydocking intervals of ship: 5 years;
• Time between main engine overhauls: 2 years
or more;
• The full service speed must be attainable
under less than favourable conditions and without exceeding 100 per cent mep, without surpassing the torque limit.
1. 1.5 – 2 % influence of wind and weather with an adverse effect on the intake water flow of the propeller. Difference between Beaufort 2 sea trial condition and Beaufort 4 – 5 average service condition. For vessels with a pro-nounced wind sensitivity, i.e. containerships with 5 – 6 tiers of boxes on deck, this value will be exceeded.
2. 1.5 – 2 % increase of ship’s resistance and mean effective wake brought about by:
• Rippling of hull (frame to frame);
• Fouling of local, damaged areas, i.e. boot top and bottom of the hull;
• Formation of roughness under paint;
• Influence on wake formation due to small
changes in trim and immersion of bulbous bow, particularly in the ballast condition. 3. 1 % frictional losses due to increase of
pro-peller blade roughness and consequent drop in efficiency, e.g. aluminium bronze propellers:
• New: surface roughness = 12 microns;
• Aged: rough surface but no fouling
= 40 microns.
4. 1 % deterioration in engine efficiency such as:
• Fouling of scavenge air coolers;
• Fouling of turbochargers;
• Condition of piston rings;
• Fuel injection system (condition and/or
timing);
• Increase of back pressure due to fouling of the exhaust gas boiler, etc.
B4
Ambient temperature consideration
B4.1
Engine air inlet: operating
tem-peratures from 45
°
C to 5
°
C
Due to the high compression ratio, RTA series die-sel engines do not require any special measures, such as pre-heating the air at low temperatures, even when operating on heavy fuel oil at part load or idling. The only condition which must be fulfilled is that the water inlet temperature to the scavenge air cooler must not be lower than 25°C.
This means that:
• When combustion air is drawn directly from the engine room, no pre-heating of the combus-tion air is necessary.
• When the combustion air is ducted from
out-side the engine room and the air temperature before the turbocharger does not fall below
5°C, no measures have to be taken.
The sea-water or the central fresh water cooling system permits the recovery of the engine’s dissi-pated heat and maintains the required scavenge air temperature after the scavenge air cooler by re-circulating part of the warm water to the scavenge air cooler.
The scavenge air cooling water inlet temperature is to be maintained at a minimum of 25°C. This means that the scavenge air cooling water will have to be pre-heated in the case of low tempera-ture operation. The required heat at low power is obtained from the lubricating oil cooler and the en-gine cylinder cooling.
B4.2
Engine air inlet: arctic conditions
at operating temperatures below
5
°
C
Under arctic conditions the ambient air tempera-tures can meet levels below –50°C. If the combus-tion air is drawn directly from outside, these en-gines may operate over a wide range of ambient air temperatures between arctic condition and tropical (design) condition (45°C).
To avoid the need of a more expensive combustion air preheater, a system has been developed that enables the engine to operate directly with cold air from outside.
If the air inlet temperature drops below 5°C, the air density increases to such an extent that the maxi-mum permissible cylinder pressure is exceeded. This can be compensated by blowing off a certain mass of the scavenge air through a blow-off device as shown in figure B5.
F10.1964
Fig. B5 Scavenge air system for arctic conditions
There are up to three blow-off valves fitted on the scavenge air receiver. In the event that the air inlet temperature to the scavenge air cooler is below 5°C the first blow-off valve vents. For each actu-ated blow-off valve, a higher suction air tempera-ture is simulated by reducing the scavenge air pressure and thus the air density. The second blow-off valve vents automatically as required to maintain the desired relationship between scav-enge and firing pressures. Figure B6 shows the ef-fect of the blow-off valves to the air flow, the ex-haust gas temperature after turbine and the firing
F10.1965
C1
RTA52U-B engine
C1.1
Engine description
The Sulzer RTA52U-B type engine is a low-speed, direct-reversible, single-acting, two-stroke engine, comprising crosshead-guided running gear, hydraulically operated poppet-type exhaust valves, turbocharged uniflow scavenging system and oil-cooled pistons.
The Sulzer RTA52U-B is designed for running on a wide range of fuels from marine diesel oil (MDO) to heavy fuel oils (HFO) of different qualities.
Main parameters:
Bore 520 mm
Stroke 1800 mm
Power (MCR) 1600 kW/cyl
Speed (MCR) 137 rpm
Mean effect. press. 18.3 bar Mean piston speed 8.2 m/s Number of cylinders 5 to 8
It is available with five to eight cylinders rated at 1600 kW/cyl to provide a maximum output for the eight-cylinder engine of 12 800 kW. Overall sizes range from 6.7 m in length to 8.6 m in height for the five-cylinder engine and 9.5 m in length to 8.6 m in height for the eight-cylinder engine. Dry weights range from 210 tonnes for the five-cylin-der to 300 tonnes for the eight-cylinfive-cylin-der model. Refer to table A1 for primary engine data.
The further development of the RTA52U-B range to provide an engine for ships concentrated around providing power and reliability at the re-quired service speeds. The well-proven bore-cooling principle for pistons, liners, cylinder covers and exhaust valve seats is incorporated with vari-able injection timing (VIT) which maintains the nominal maximum firing pressure within the power range 100 per cent to 85 per cent.
Refer to figure C1 and the following text for the
Remark: * The direction of rotation looking always from the propeller towards the engine is clockwise as standard.
F10.4163
Note: This illustration of the cross section is considered as general information only
Fig. C1 Sulzer RTA52U-B cross section
1. Welded bedplate with integrated thrust
bearings and large surface main bearing shells.
2. Sturdy engine structure with low stresses and high stiffness comprising A-shaped fabricated double-wall columns and cylinder blocks attached to the bedplate by pre-tensioned vertical tie rods.
3. Fully built-up camshaft driven by gear wheels housed in a double column located at the driving end.
4. A combined injection pump and exhaust valve
actuator unit for two cylinders each. Camshaft driven fuel pump with double spill valves for timing fuel delivery to uncooled injectors. Camshaft-driven actuator for hydraulic drive
5. Standard pneumatic control – fully equipped local control stand. Diesel Engine CoNtrol and optImizing Specification (DENIS-6), standard set of sensors and actuators for control, safety and alarms. Speed control system according to chapter D2.3.
6. Rigid cast iron cylinder monoblock or iron
jacket moduls bolted together to form a rigid cylinder block.
7. Special grey cast iron, bore-cooled cylinder liners with load dependent cylinder lubrication.
8. Solid forged or steel cast, bore-cooled
cylinder cover with bolted-on exhaust valve cage containing Nimonic 80A exhaust valve.
9. Constant-pressure turbocharging system
comprising exhaust gas turbochargers and auxiliary blowers for low-load operation. 10. Uniflow scavenging system comprising
scavenge air receiver with non-return flaps. 11. Oil-cooled piston with bore-cooled crowns
and short piston skirts.
12. Crosshead with crosshead pin and single-piece white metal large surface bearings. Elevated pressure hydrostatic lubrication.
13. Main bearing cap jack bolts for easy assembly and disassembly of white-metalled shell bearings.
14. White-metalled type bottom-end bearings. 15. Semi-built crankshaft.
The following option is also available:
C1.2
Engine data
C1.2.1
Reference conditions
If the engine is operated in the ambient condition range between reference conditions and design (tropical) conditions its performance is not af-fected.
The engine performance data BSFC, BSEF and tEaT in figures C2, C3 and C4 are based on refer-ence conditions as shown below. They are fol-lowing the ISO Standard 3046-1:
• Air temperature before blower : 25°C
• Engine room ambient air temp. : 25°C
• Coolant temp. before SAC : 25°C for SW
• Coolant temp. before SAC : 29°C for FW
• Barometric pressure : 1000 mbar
The reference value for the fuel lower calorific value (LCV) follows an international marine con-vention. The specified LCV of 42.7 MJ/kg differs from the ISO Standard.
C1.2.2
Design conditions
The design data for the ancillary systems are based on standard design (tropical) conditions as shown below. They are following the IMO-2000 recommendations.
• Air temperature before blower : 45°C
• Engine ambient air temp. : 45°C
• Coolant temp. before SAC : 32°C for SW
• Coolant temp. before SAC : 36°C for FW
• Barometric pressure : 1000 mbar
The reference value for the fuel lower calorific value (LCV) of 42.7 MJ/kg follows an international marine convention.
C1.2.3
Ancillary system design
parameters
The layout of the ancillary systems of the engine bases on the performance of its specified rating point Rx (CMCR). The given design parameters must be considered in the plant design to ensure a proper function of engine and ancillary systems.
• Cylinder water outlet temp. : 85°C
• Oil temperature before engine : 45°C
• Exhaust gas back pressure
at rated power (Rx) : 300 mm WG
The engine power is independent from ambient conditions. The cylinder water outlet temperature and the oil temperature before engine are system-internally controlled and have to remain at the spe-cified level.
C1.2.4
Estimation of engine
performance data
To estimate the engine performance data BSFC, BSEF and tEaT for any engine rating Rx in the de-fined rating field, figures C2, C3 and C4 may be used.
The estimation of the performance data for any en-gine power will be done with the help of a computer program, the so-called winGTD, which is enclosed in this book in the form of a CD-ROM.
If needed we offer a computerized information ser-vice to analyse the engine’s heat balance and de-termine main system data for any rating point within the engine layout field.
For details of this service please refer to chapters C1.5 and F.
The installation of the winGTD and the hardware specification are explained in chapter F.
C1.2.4.1
Estimating brake specific fuel
consumption (BSFC)
F10.3877
Fig. C2 Estimation of BSFC for Rx
Example:
Estimation of BSFC for 7RTA52U-B CMCR (Rx) specified and for reference condition:
Power (R1) = 11 200 kW Speed (R1) = 137 rpm Power (Rx) = 85.0 % R1 = 9 520 kW Speed (Rx) = 89.8% R1 = 123 rpm BSFC (R1) = 174 g/kWh BSFC at Rx-point: DBSFC – 1.9 g/kWh (figure C2) BSFC (Rx) = 174 – 1.9 = 172.1 g/kWh
For design (tropical) conditions add 3 g/kWh to the calculated values.
Please note that any BSFC guarantee must be subject to confirmation
by the engine manufacturer.
Derating and part load performance figures can be obtained from the winGTD-program which is en-closed in this book in the form of a CD-ROM.
C1.2.4.2
Estimating brake specific
ex-haust gas flow (BSEF)
F10.3878
Fig. C3 Estimation of BSEF for Rx
Example:
Estimation of BSEF for 7RTA52U-B CMCR (Rx) specified and for reference condition:
Power (R1) = 11 200 kW Speed (R1) = 137 rpm Power (Rx) = 85.0 % R1 = 9 520 kW Speed (Rx) = 89.8% R1 = 123 rpm BSEF (R1) = 8.2 kg/kWh BSEF at Rx-point: DBSEF + 0.17 kg/kWh (figure C3) BSEF (Rx) = 8.2 + 0.17= 8.37 kg/kWh
For design (tropical) conditions subtract 0.4 kg/kWh from the calculated values.
The estimated brake specific exhaust gas flows are within a tolerance of ± 5 per cent. An increase of BSEF by 5 per cent corresponds to a decrease of the tEaT by 15°C.
Please note that any BSEF figure must be subject to confirmation
by the engine manufacturer.
Derating and part load performance figures can be obtained from the winGTD-program which is en-closed in this book in the form of a CD-ROM.
C1.2.4.3
Estimating temperature of
exhaust gas after turbocharger
(tEaT)
F10.3879
Fig. C4 Estimation of tEaT for Rx
Example:
Estimation of tEaT for 7RTA52U-B CMCR (Rx) specified and for reference condition:
Power (R1) = 11 200 kW Speed (R1) = 137 rpm Power (Rx) = 85.0 % R1 = 9 520 kW Speed (Rx) = 89.8% R1 = 123 rpm tEaT (R1) = 275°C tEaT at Rx-point: DtEaT –9°C (figure C4) tEaT (Rx) = 275 – 9 = 266 °C
For design (tropical) conditions add 30°C to calculated values.
The estimated temperatures after turbocharger are within a tolerance of ± 15°C. An increase of tEaT by 15°C corresponds to a decrease in BSEF of 5 per cent.
Please note that any tEaT figure must be subject to confirmation
by the engine manufacturer.
Derating and part load performance figures can be obtained from the winGTD-program which is en-closed in this book in the form of a CD-ROM.
C1.2.5
Vibration aspects
As a leading designer and licensor we are con-cerned that satisfactory vibration levels are ob-tained with our engine installations. The assess-ment and reduction of vibration is subject for continuous research and we have developed ex-tensive computer software, analytical procedures and measuring techniques to deal with the subject. For successful design the vibration behaviour needs to be calculated over the whole operating range of the engine and propulsion system.
C1.2.5.1
Torsional vibration
This involves the whole shafting system compris-ing crankshaft, propulsion shaftcompris-ing, propeller, en-gine running gear, flexible couplings and power take off. It is caused by gas and inertia forces as well as by the irregularities of the propeller torque. It is vitally important to limit torsional vibration in order to avoid damage to the shafting. If the vibra-tion at a critical speed reaches dangerous stress levels, the corresponding speed range has to be passed through rapidly (barred-speed range). However, barred-speed ranges can be reduced, shifted, and in some cases avoided by installing a heavy flywheel at the driving end and/or a tuning wheel at the free end or a torsional vibration damper at the free end of the crankshaft.
Torsional vibration dampers of various designs are available to reduce energy on different levels of vibration.
Lower energy vibrations are absorbed by viscous dampers.
Higher energy vibrations are absorbed by a spring loaded damper type. In this case the damper is supplied with oil from the engine’s lubricating sys-tem and the heat dissipated can range from 20 kW to 60 kW depending on the size of the damper.
C1.2.5.2
Axial vibration
The shafting system is also able to vibrate in the axial direction. This vibration is due to the axial ex-citations coming from the engine and the propeller. In order to limit the influence of these excitations and limit the level of vibration, an integrated axial detuner/damper is fitted to the crankshaft of all Sul-zer RTA engines. In rare cases (e.g. five-cylinder engines and very stiff intermediate and propeller shafts) the influence of axial vibration may be ap-parent at the engine top. This can be reduced by longitudinal friction stays attached to the ship’s structure.
C1.2.5.3
Hull vibration
The hull and accommodation are susceptible to vibration caused by the propeller, machinery and sea conditions. Controlling hull vibration is achieved by a number of different means and may require fitting longitudinal and lateral stays to the main engine and installing second order balancers on each end of the main engine. These balancers are available for our engines and involve counter-weights rotating at twice the engine speed. There are also electrically driven secondary balancers available for mounting at the aft end of the ship and which are tuned to the engine’s operating speed and controlled in accordance with it.
Eliminating hull vibration requires co-operation be-tween the propeller manufacturer, naval architect, shipyard and engine builder.
C1.2.5.4
Estimation of engine vibration
data
The RTA52U-B engine has been designed to elim-inate free forces and minimize unbalanced exter-nal couples of first and second order.
However, different numbers of cylinders, rating point and engine tuning affect the magnitude of
Figure C5 is a representation of the engine show-ing the free couples of mass forces and the torque variation about the centre lines of the engine and crankshaft.
M1V is the first order couple having a vertical com-ponent.
M1H is the first order couple having a horizontal component.
M2V is the second order couple having a vertical component.
∆M is the reaction to variations in the nominal torque.
Reducing the first order couples is achieved by counterweights installed at both ends of the crank-shaft.
The second order couple is larger on 5 and 6 der engines than it is on engines of 7 and 8 cylin-ders, however it is reduced to acceptable levels by fitting second order balancers.
It is important to establish at the design stage what the ship’s vibration form is likely to be. Table C1 will assist in assessing the effects of fitting the chosen RTA52U-B.
F10.1931
Fig. C5 External couples and forces
Free couples of mass forces Torque variation
e rs R1 / R2 R3 / R4 R1 R2 R3 R4 n der e d 1st order 2nd order e d 1st order 2nd order c ylin pee d
with with without with*) pee
d
with with without with*)
ber of c y n gine s p standard counter-weights non-standard counter-weights 2nd-order balancer n gine s p standard counter-weights non-standard counter-weights 2nd-order balancer u m b En M1V M1H M1V M1H M2V M2V En M1V M1H M1V M1H M2V M2V ∆M ∆M ∆M ∆M Nu [rpm] [±kNm] [±kNm] [±kNm] [±kNm] [±kNm] [±kNm] [rpm] [±kNm] [±kNm] [±kNm] [±kNm] [±kNm] [±kNm] [±kNm] [±kNm] [±kNm] [±kNm] 5 126 112 – – 1271 565 81 72 – – 819 364 710 717 698 695 6 137 0 0 – – 884 144 110 0 0 – – 570 93 500 556 500 512 7 76 65 – – 257 – 49 42 – – 166 – 391 451 391 411 8 260 216 – – 0 – 168 139 – – 0 – 275 350 275 305
Remarks: *) These data refer to engines equipped with ELBA (electrical balancer) at the free end together with a gear-driven
integrated balancer at the driving end.
As mentioned earlier the results of vibration analy-sis may lead to fitting engine stays. The lateral components of the forces acting on the cross-heads may induce lateral rocking, depending on the number of cylinders and the firing sequence. These forces may be transmitted to the engine seating structure, and induce local vibrations. These vibrations are difficult to predict and strongly depend on the engine foundation, frame stiffness and pipe connections. For this reason, we recom-mend consideration of lateral stays (please refer to table C3 ‘Countermeasures for dynamic effects’), either of the hydraulic or friction type early in the design stage.
Figure C6 illustrates typical attachment points for lateral stays. Friction stays are installed on the en-gine exhaust side only.
F10.3588