Training Manual

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Company

Owner

Top Drive

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Varco Technical Education Centre

Montrose Scotland

TOP DRIVE

Training Manual

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Varco Technical Education Centre

Montrose Scotland

TOP DRIVE

Training Manual

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Training Manual June 99

Chapter 1 Preparation

Preinstallation checklist

The following assumes that all preinstallation planning and rig-up has been accomplished prior to installation of the TDS. This includes:

1. Guide rails and bracing are installed and inspected to conform to Varco specification and installation tolerances (Figures 1, 2, and 3).

2. Stops are ready for installation at the bottom of the rails. 3. Hydraulic and air standpipes are installed in the derrick,

flushed clean and pressure tested. Water piping is installed, flushed and pressure tested as well for configurations with closed loop cooling systems.

4. All electronics are installed up to the derrick junction box: DC power leads, AC leads for blower motor, and control/ alarm signals.

5. The transfer panel is installed.

6. Rigging of the tong lines, etc. are inspected to ensure that they will not foul with the TDS and other rig equipment.

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Chapter 2 Installation

Derrick electrical termination kit

Installation

Refer to Figures 1, 2 and 3 for typical mounting dimensions of the plate assembly. Mount it at racking board height within 15' of the service loop support bracket. Remember to provide

convenient access for wiring and maintenance.

Usually, mounting the plate so that the J-box is four to five feet above the walk-around and near the service loop support bracket is adequate. If a walk-around does not exist, then construct a work platform to allow access to the J-boxes. Manufacture appropriate brackets and clamps to attach the plate to the derrick structure.

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OPERATIONAL CLEARANCE BETWEEN TOP DRIVE & NEAREST GIRT OR FASTLINE SHOULD BE 3“ MINIMUM

DOLLY OVERHANG

± 1/4"

OVER FULL LENGTH

± 3/8" OVER FULL LENGTH

± 1/8" WITHIN 25' OF FLOOR

± 3/8 OVER FULL LENGTH

± 1/8" WITHIN 25' OF FLOOR C WELL_L 10' 6" +0"/-4" SUPPORT SPACING MAXIMUM RAIL 16 FT FOR W12x53 RAILS 25 FT FOR W14x74 RAILS NEAREST GIRT GUIDE RAILS L C WELL L C RAIL SPLICE CLEARANCE DRILL FLOOR 6" RAIL STOP TDS BACK L C RAIL L C WELL SPLICE PLATES OR BOLTS ARE NOT PERMISSABLE ON INSIDE SURFACES OF BEAM 39 X 66 W14X74 48 X 62 W14X74 30 X 72 W12X53 30 X 72 W14X74 3.3 3.3 2.3 3.3 0 0 1.6 0.5 RAIL SIZE SPLICE CLEAR DOLLY OVERHANG INCHES GUIDE DOLLY CONFIG L C RAIL C RAILL

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10' 6"+0"/-4" _{7 FT REF}

73 FT. MUD HOSE CONNECTION

83 FT. HYD, AIR & WATER STANDPIPE HEIGHT & SERVICE LOOP BRACKET LOCATION

TYPICAL EQUIPMENT STACK-UP

* CUSTUMER SUPPLIED ** VARCO SUPPLIED 86 FT. SERVICE LOOPS B B 16.00

ELECTRICAL SERVICE LOOP ** BRACES *

INSTRUMENT J-BOX ** MOTOR J-BOX ** DERRICK J-BOX PLATE

16.0 16.0 16.0 MUST SUPPORT 4000 LBS VIEW A-A

TYPICAL SERVICE LOOP TERMINATION

GUSSETS * EXISTING GIRT * VIEW B-B HYDRAULIC STANDPIPES TO BE 1-1/2” SCHED 80 PIPE* AIR STANDPIPES TO BE 1-1/2” SCHED 40 PIPE* WATER STANDPIPES TO BE 2” SCHED 40 PIPE* CLEARANCE HOLE FOR .75 DIA BOLT 4 PLACES CONVENIENT WORKING HEIGHT ABOVE WALKAROUND SERVICE LOOP BRACKET** 75 FT. MUD HOSE REF A A

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Training Manual June 99 Rail Stops 42,600 LBS for a typical TDS-3S 48,000 LBS for a typical TDS-4S 52,000 LBS for a typical TDS-7S Motor Frame Setback L L L L Rails 9'3" TDS-3S 10'3" TDS-4S _{7'0" TDS-3S} 8'0"TDS-4S, TDS-6S

Rail Loading while Drilling - 38,000 FT LBS for TDS-3S, 60,000 FT LBS for TDS-4S, 68,000 FT LBS for TDS-6S, and 34,000 FT LBS for TDS-7S. Rail Spacing TDS-3S TDS-4S Load L - LBS 39 x 66 3450 TDS-6S --48 x 62 3680 --30 x 72 3170 91/101 x 108 --5450 5800 5000 3330 3090 3290 2840 3780 TDS-7S P P

Rail Loading with TDS in Setback position

Rail Spacing 39 x 66 48 x 62 30 x 72 TDS-3S TDS-4S Load P - LBS 18,600 18,600 17,500 18,900 18,900 17,800

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Rail Stops 48,000 LBS for a typical TDS-4H Motor Frame Setback L L L L Rails 10'3" TDS-4H 7'0"TDS-4H,

Rail Loading with TDS in Setback position

Rail Spacing TDS-4H Load P - LBS 39 x 66 48 x 62 30 x 72 18,900 18,900 17,800

Rail Loading while Drilling - 60,000 FT LBS

Rail Spacing TDS-4H Load L - LBS 39 x 66 5450 48 x 62 5800 30 x 72 5000 91/101 x 108 3330

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Wiring

The electrical installation requires routing power to the transfer panel and then to the TDS through the service loops (Figure 4). In addition, control cables are required between the service loop, the transfer panel, the SCR, the TDS driller’s console, the SCR’s driller’s console, the hydraulic and water pumps and the drilling recorder. Transfer Panel #12AWG/20C #10AWG/4C #14AWG/2 Pr Shld #6AWG/2C* Shunt Field Top Drive System Derrick A.C. J Box Derrick Power J Box Service Loop Rotary Table Existing Power Cables

#14AWG/2 Pr Shld #12AWG/3C #14AWG/37C #12AWG/20C #12AWG/20C #16AWG/10C #12AWG/20C

#10AWG/4C #10AWG/4C #6AWG/4C #6AWG/4C

#12AWG/3C #14AWG/2 Pr Shld #10AWG/4C #16AWG/10C #16AWG/10C #16AWG/10C #16AWG/10C #6AWG/2C* Shunt Field #16AWG/10C SCR Room AC Power E/P Torq E/P RPM RBS Controls #12AWG/3C TDS Driller's Console Existing Driller's Console HYD Pump #1 HYD Pump #2 Water_Pump #1 Water Pump #2 (4)646MCM*

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The cable requirements, depending on options selected are: Cable Runs

646MCM (4 Shunt) SCR room to transfer panel (8 Series) Transfer panel to derrick J-box

Transfer panel to rotary #6AWG/2C (Shunt only) SCR Room to transfer panel

Transfer panel to derrick J-box Transfer panel to rotary #6AWG/4C AC Power to hydraulic pumps #10AWG/4C AC Power to water pumps

AC Power to transfer panel Transfer panel to derrick J-box #12AWG/20C Transfer panel to derrick J-box

Transfer panel to hydraulic pumps Transfer panel to water pumps #12AWG/3C Transfer panel to RBS unit

Transfer panel to driller’s console RBS unit to driller’s console #14AWG/37C Transfer panel to driller’s console #14AWG/2PR SHLD Transfer panel to derrick J-box

Transfer panel to driller’s console Transfer panel to drilling recorder #16AWG/10C Transfer panel to SCR console

Transfer panel to SCR room Purge control system (not shown)

#12AWG/3C Purge control unit to transfer panel Isolation unit to floor air control unit

Transfer panel protection unit to isolation unit #16AWG/10C Purge control unit to transfer panel

Driller’s console protection unit to isolation unit #14AWG/2PR SHLD Transfer panel to derrick J-box

Terminate the J-boxes per the electrical schematic. Follow applicable electrical codes during installation. Cable glands are provided for the service loop cables. Cable glands for the incoming power, control and signal cables are not provided.

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Plumbing

The plumbing connections should terminate near the service loop bracket. The mating halves are preassembled on the service loop. Specifications for specific lines are described in the following sections.

Hydraulic

Hydraulic lines should be cleaned and pickled, black pipe lines (one pressure and one return) 1 1/2" or 2" schedule 80 pipe. Install shut-off valves at the drill floor or racking board level. The derrick connections are reduced to 1" NPT female pressure and fluid return for connection to the service loop.

Air

Air lines should be schedule 40, 1" or 1 1/2" pipe in the case of the purge supply for the TDS. Install a shut-off valve at drill floor or racking board level. The air lines connect to the filtered and lubricated supply. The derrick connections are reduced to 1" NPT female for the purge line (if required) and 1/2" for the air line in order for the fluids service loop to match.

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Do not connect purge air lines to the lubricator. Only use clean, dry air in the purge air system.

Water

The two cooling lines should be schedule 40, 2" pipe. Install shut-off valves at the drill floor or racking board level. See the cooling system specifications for water supply requirements. The derrick connections are reduced to 1 1/4" NPT female pressure and return for connection to the fluids service loop.

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required.

The connection on the main shaft is 7-5/8 API regular left hand. The bail bumper on the swivel faces the guide rails. On some swivel/rail setback combinations, the bumper side ears may require trimming to clear the motor guide dolly.

4. Loosely install the bearing shield around the flange on the main shaft with the T-bolt clamp supplied. After the main shaft is stabbed into the quill shaft, adjust the shield and tighten the clamp.

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September 16, 1996

TDS-4H Installation and commissioning 17

5. Use the four lift slings from the crane, one attached at each corner of the guide dolly, to lift the top drive motor and dolly assembly onto the rig floor. If possible, set it on the rig floor with the crane - do not drag it up the V-door. Position it on the rotary table with the swivel end under the guide rails. The slings must be a minimum of 15' long (equal length) and capable of lifting 40,000 lb combined. (BOP lift slings are usually adequate.)

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September 16, 1996

6. Attach lifting slings to the pad eyes located at the swivel end of the motor frame and lift the TDS into the guide rails.

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On some configurations it may be necessary to remove the upper roller brackets from the dolly to allow the unit to engage the guide rails.

7. Once the TDS is fully engaged on the guide rails, install the stops at the bottom of the guide rails and lower the TDS onto the stops.

8. Apply a liberal amount of grease to the main shaft from 6" below the splines up to the top flange. Also grease the top and bottom 18"of the quill shaft I.D. Pack both the main shaft and bull gear splines flush with grease. Check the O-ring in the groove located 12" inside the quill shaft to be sure it is greased and located properly.

9. Spread apart the swivel links and stab the swivel/main shaft through the quill shaft with care, until the drive splines are fully engaged. Slide the swivel links onto the extended bail pins and install the retainers with the bolts, lockwashers and safety wire supplied.

10. Slide the link adapter onto the main shaft and support it up against the rotating head with adequate rigging and an air winch. Be certain that the link tilt mounting bosses are opposite from the torque wrench mounting clevis on the rotating head.

11. Slide the landing collar retainer onto the drive stem as shown in Figure 4. Install the O-ring in the uppermost groove on the stem. Load the O-ring and remaining grooves with a

waterproof grease. Place the split landing collar around the grooves of the drive stem, and drive in the remaining roll pin. Grease the O.D. liberally, and slide the retainer down,

covering the split landing collar. Use a hammer and drift to bend all 32 tabs on the retainer to secure the split landing collar. Wipe off excess grease.

12. Use the pipehandler to tighten the connection between the lower IBOP/saver sub assembly to the upper IBOP.

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September 16, 1996

Drive Stem Landing Collar Retainer Landing Collar Retainer Tabs Safety Link (4) Roll Pin (4) Split Landing Collar (2) O-Ring

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September 16, 1996

13. Pull up on the release handle and unlock the rotating head. Rotate the link adapter and the rotating head so that the mounting point for the torque wrench is at the front of the tool. Raise the torque wrench with the air winch and pin into place. Adjust hanging position per the procedure described in Book 4. Rotate the pipehandler assembly to the rear and connect the two air hoses and two hydraulic hoses. Quick disconnects on the hoses allow connection in only one way so that the hoses cannot be interchanged.

14. Connect the hose to the back of the link tilt actuator. Use the four bolts, lockwashers and safety wire provided to install the link tilt acutator to the link adapter. Connect the opposite end of the hose to the quick disconnect on the rotating head assembly.

15. Install the elevator links and drill pipe elevator. Attach the link tilt clamps to the bails (U-bolts on the inside). Allow for 1/2" slack in the chains.

16. Install the counterbalance system as follows (Figure 5): a. Install pear links to ears on hook-block.

b. With the hook supporting the top drive, measure distance from bottom of pear link to top of mounting lug on swivel link (Dimension A).

c. Subtract 37 1/4" from dimension A.

d. Cut chain to the length obtained in step c (measure inside chain links per illustration). The tolerance is: +3 1/4"/-0". e. Assemble remaining components and install per the

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September 16, 1996

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September 16, 1996

17. Attach the service loops to the bracket on the top drive frame. Use the cable clamps provided on the motor frame to route the electrical cables over the gear box and into the junction boxes. The front guard swings aside for access to the junction boxes by removing the attachment bolts on one side.

Use the electrical schematic (refer to the engineering

drawings) to make the connections. Be certain that the cables are securely tied or clamped to the structure along their length. Route the hoses to the bulkhead and plug in the quick disconnects. Follow the stamped code numbers to confirm each type and identify spares.

18. Attach the S-tube to the swivel gooseneck and the side of the motor frame as follows (Figure 6):

a. Makeup the upper union just before clamping S-tube to side of motor frame.

b. Install the drill pipe rubber onto the S-tube aligned with mounting saddle on the frame.

c. Attach the mud hose to the bottom connection of S-tube. d. Position 15° S-tube elbow on bottom of S-tube to adjust

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September 16, 1996

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August 22, 1997

Rig-up procedure

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Refer to the engineering drawings to install the TDS.

1. Using four lift slings from the crane, one attached at each corner of the guide dolly, lift the TDS motor and dolly assembly to the V-door.

2. Attach the lifting slings from the hook or block to the pad eyes located at the swivel end of the motor support bonnet and lift the TDS into the guide rails. The slings must be a minimum of 15' long (equal length) and capable of lifting 40,000 lb combined. (BOP stack lift slings are usually adequate.)

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On some configurations it may be necessary to remove the upper roller brackets from the dolly to allow the unit to engage the guide rails.

3. Once the TDS is fully engaged on the guide rails, install the stops at the bottom of the guide rails and lower the TDS onto the stops.

4. Slide the link adapter onto the drive stem and support it up against the rotating head with adequate rigging and an air winch. Be certain that the link tilt mounting bosses are opposite from the torque wrench mounting clevis on the rotating head.

5. Slide the landing collar retainer onto the drive stem as shown in Figure 5. Install the O-ring in the uppermost groove on the stem. Load the O-ring and remaining grooves with a

waterproof grease. Place the split landing collar around the grooves of the drive stem. Grease the O.D. liberally, and slide the retainer down, covering the split landing collar. Use a hammer and drift to bend all 32 tabs on the retainer to secure the split landing collar. Wipe off excess grease.

6. Use the installation procedure in the IBOP Service Manual (included as a separate book in this manual) to install the pipehandler assembly.

7. Use the pipehandler to tighten the connection between the lower IBOP/saver sub assembly to the upper IBOP.

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TDS-4S Installation 17 Drive Stem Landing Collar Retainer Landing Collar Retainer Tabs Split Landing Collar (2) O-Ring

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August 22, 1997

8. Connect the hose to the back of the link tilt actuator. Use the four bolts, lock washers and safety wire provided to install this assembly to the link adapter. Connect the opposite end of the hose to the quick disconnect on the rotating head assembly. 9. Install the elevator links and drill pipe elevator. Attach the

link tilt clamps to the bails (U-bolts on the inside). There should be about 1/2 inch slack in the chains.

10. Install the counterbalance system as illustrated in Figure 6. When using chain, use the following procedure to determine the chain length required:

a. Install pear links to ears on hook-block.

b. With the hook supporting the TDS, measure the distance from the point of contact inside the pear link to the top of the mounting lug on the integrated swivel bail. c. Subtract 37 1/4" from the measurement in step b. d. Cut the chain to the length obtained in step c. The

tolerance is: +3-1/4" or -0".

e. Assemble remaining components and install per Figure 6.

Pear Link

Hydraulic Accumulator

(Inside Motor Frame)

Motor Frame & Guide Dolly Assy.

Counterbalance Cylinder Assy. (2) Connecting Link Counterbalance Manifold

(On Guide Dolly)

Counterbalance Lug (Bolted to Bail) Integrated Swivel Bail

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TDS-4S Installation 19

11. Attach the service loops to the bracket on the TDS dolly frame. Using the cable clamps provided on the motor support bonnet, route the electrical cables over the gear box and into the junction boxes. The front guard folds down for access to the junction boxes.

Use the electrical schematic (refer to the engineering

drawings) to make the connections. Be certain that the cables are securely tied or clamped to the structure along their length. Route the hoses to the bulkhead and plug in the quick disconnects. Follow the stamped code numbers to confirm each type, and identify spares.

12. Attach the S-tube to the swivel gooseneck and the side of the motor frame as follows:

a. Make up the upper union just before clamping the S-tube to the side of the motor frame.

b. Install the drill pipe rubber onto the S-tube aligned with the mounting saddle on the frame.

c. Attach the mud hose to the bottom connection of the S-tube.

d. Position the 20° S-tube elbow on the bottom of the S-tube to adjust the hanging direction of mud hose. 13. Remove the exhaust duct shipping cover from the spark arrestors on the air exhaust duct at each side of the DC motor. Save the covers for use during future shipping or storage.

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Never operate the top drive with the exhaust duct covers attached to the spark arrestors on the air exhaust ducts. Doing so severely restricts air flow through the motor, causing

overheating and potential damage. They can also fall off during operation and injure personnel working below. Attach the covers only during shipping and storage.

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August 22, 1997

Counterbalance system

Figure 6 illustrates the installation arrangement for this system. Please see the Maintenance and troubleshooting book for the adjustment procedures.

This assembly is pre-charged when it is shipped by land or water transport. When this assembly is shipped by air freight, it must be pre-charged according to the instructions inthe Maintenance and troubleshooting book.

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TDS-4S Installation 21

Motor alignment cylinder system

Figure 7 shows the motor alignment cylinder installed on a typical motor frame.

The split shipping brace, shown exploded from the cylinder rod, is only removed after unit is fully installed. If the brace is removed before the hydraulic system is powered, the motor will tend to rotate on its trunnions.

If the cylinder is removed for service, use the three bleed holes (located along the top of the cylinder barrel) to remove trapped air from the cylinder before operating the unit. Refer to the Maintenance and troubleshooting book for the adjustment procedure, as this dimension can vary.

Motor Alignment

Cylinder

Motor Frame Dolly (Ref)

Split Shipping

Brace

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August 22, 1997

Driller’s controls and instrumentation

The controls and instrumentation described in the following sections are, or must be, supplied for operation of the TDS system.

Driller’s console

Mount the driller’s console within easy reach and in plain view of the driller while he is operating the drawworks brake and

clutches. The gauges must be easily seen by the driller during drilling operations. Provide appropriate cable glands for the electric cables.

Throttle and torque limit controls

The throttle and torque limit controls are the standard controls used for the independent rotary drive table. If not using an independent rotary drive, then these controls must be added by the SCR manufacturer.

Wiring

Refer to the electrical schematics in the engineering drawings.

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Customers who choose to use control systems not manufactured

by Varco should be aware that Varco systems are specifically designed with operational interlocks and safety devices to prevent possible injury to personnel or damage to the system. Other systems must meet Varco requirements. Varco highly recommends the use of its system as it is specifically made for use with the TDS system.

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Service loops

Installation

Install the service loops as follows:

1. Fabricate the appropriate brackets and clamps to attach the service loop mounting bracket to the derrick structure. 2. Place the service loop derrick mounting bracket at the height

specified on the derrick interface drawing provided in the engineering drawings. Locate the bracket on the side of the derrick adjacent to the hinges on the TDS and as far as practical toward the corner where the guide rail bracing is attached. The bracket must be located far enough from the corner to insure the loops do not catch under the guide rails during operations, but far enough back to provide clearance for tong lines, the stabbing board, tugger lines, etc.

3. Do not unpack the service loops from the shipping protective crate until they are ready to hang in the derrick. Lift the service loops onto the rig floor (still in the crates) and then remove them from the crates with the lifting eyes provided.

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Use care in lifting gear rigging so as not to damage electrical

conductors. Use lifting eyes only. Do not bend the service loops tighter than a three foot bend radius. Tighter bends damage the loops. 4. Attach a sling to the top drive end of the service loop and lift

using the lifting eyes only. Allow enough room for the 86-foot long service loop to hang and untwist.

5. Use the lifting eyes to pull the derrick end of the loop through the "V" door and attach it to the air tugger. Hoist this end of the loop into the derrick while slacking off at the crane end. Do not drag the loop on any sharp areas on the derrick . Disconnect the crane from the sling and continue hoisting the loop into the derrick.

6. Check that the derrick end of the loop is hanging toward the crown. Attach the derrick end to the derrick service loop bracket and hold in place with flange clamps (Figures 1 and 2).

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August 22, 1997

7. Pick up the TDS end of the loops and attach them to the service loop bracket at the bottom of the motor frame.

8. Complete the terminations of the two loops as outlined in the following sections.

Electrical loop

1. Connect the pre-terminated wire ends at the motor J-boxes using the appropriate glands. Refer to the electrical schematic provided to ensure proper terminal block assignments. 2 Cut wires and cables to length and terminate them at the

derrick end to attach them to the derrick J-boxes. Terminal ends and lugs are supplied, but proper assembly

equipment (crimping pliers, wire strippers, and hydraulic crimper for the DC power lugs with the correct dies for the cable) must be provided by the installer. Installation practices should comply with applicable electrical codes (i.e., NEC, etc.).

Fluids loop

1. Before connecting the hoses from the service loop, be certain that the service stand pipes have been flushed free of any contamination.

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Use only 10 wt. hydraulic oil or non-detergent motor oil as a lubricant in the air system. Use of any other type of oil (i.e., Marvel Mystery Oil, etc.) or synthetic additive will cause the seals in the air valves to swell and cease to function.

2. Plug the quick disconnects into the appropriate mating end on the TDS. The quick disconnects are arranged to connect only one way so that the hoses cannot be mixed up. The hydraulic and air lines are identification stamped at both ends so they can be verified and connected properly.

An assortment of pipe fittings are supplied with the termination kit to attach the fluid service loop hoses to the top of the standpipes in the derrick (Figure 2).

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3. Connect the service loop to the standpipes, noting the codes (i.e., A for air, H for hydraulic, etc.) to separate the hoses.

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The hoses in the fluid loop only extend 11' from the mounting bracket. It may be necessary to make jumper hoses to reach the standpipes.

Air loop

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To reduce the possibility of accidental opening of the air operated elevator attach the airlines from the air operated elevators to the spare port S1 on the rotating head whenever possible. Port S1 is located next to the hydraulic return port in the rotating head. Port S2 is next to the hydraulic press port.

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Chapter 3 Commissioning

Checkout procedure

1. Turn on the hydraulic and air power and check for leaks. Repair as required.

2. Turn on the electric power (driller’s controls only). 3. Check the function of switches and solenoids. There is an

audible click when each solenoid is actuated.

4. Actuate the link tilt. Be sure that it operates smoothly and the elevator reaches a joint in the mousehole.

5. Adjust the intermediate stop so that the elevator clears the monkey-board when actuated. Refer to the Maintenance and troubleshooting book if a problem occurs.

6. Actuate the motor brake. There is a loud sound as the air escapes when the brake releases.

7. Move the make/break valve located on the manifold at the back of the pipehandler torque wrench to the BREAK position. 8. Turn on the hydraulic power supply and adjust the pressure

reducing valve (also located on the torque wrench manifold) to the appropriate pressure for the lower IBOP connection.

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August 22, 1997

9. Return the Make/Break valve to the MAKE position. 10. Torque the connection between the upper and lower safety

valves. The torque wrench automatic sequence is adjusted at the factory, but be sure that it follows the proper sequence. If necessary, refer to the Maintenance and troubleshooting book for the adjustment procedure.

11. Push and hold the control button on the driller’s console a sufficient number of times to make up the connection. 12. Make up the lower IBOP to the saver sub.

13. Reset pressure to the appropriate setting for drill pipe

connections (you can preset the pressure with the Make/Break valve in the MAKE position).

14. Use the procedure outlined in the Maintenance and Troubleshooting book to adjust the safety valve actuator mechanism.

15. Actuate the safety valve. Verify that the stroke adjustment is correct and that no binding occurs.

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It is extremely important to verify that the stroke adjustment is correct and that no binding occurs as the valve will fail prematurely (wash out) if it does not open and close fully.

16. Verify that the indicator light on the driller’s console lights up when the safety valve is closed.

17. Assign the TDS at the driller’s console and check that the blower operates.

18. Advance the throttle and be sure that the motor is operating properly in both directions.

19. Calibrate the Amp meter and RPM meter.

20. With the hydraulic power unit off, bleed down the TDS accumulators (HYD SIDE, not gas side).

21. Remove the split shipping brace (Figure 12 book 1) from the motor alignment cylinder.

22. Open the two flow control valves 1-1/2 turns off their seats. 24. Set a joint of drill pipe in the slips.

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25. Bring the TDS down as if stabbing the saver sub into box. The pin and box should be in alignment. If adjustment is necessary, use the following procedure:

a. Measure how far and in what direction (toward or away from the rails) the pin must move to line up with the drill pipe box.

b. Turn off the hydraulic power unit and bleed down the cylinder accumulator (open the needle valve on the back of the manifold). This allows the motor alignment cylinder to relax and the motor to rotate on its trunnions until the integrated swivel bail contacts the motor support bonnet.

c. Loosen the lock tab and jam nut on the cylinder clevis. d. With a wrench located on the cylinder rod flats, screw the

rod into or out of the clevis, in the same direction the saver sub pin is to be moved.

e. Secure the jam nut and lock tab.

f. The nominal position of the two cylinder flow control valves is 1-1/2 turn off their seats. If you experience heavy drill pipe vibration, first attempt to control it with non-rotating stabilizers if the casing shoe is close to the surface. If motor movement becomes excessive due to continued vibration, (more than 1/2" of total cylinder stroke) close the flow controls to 3/4 turn off their seats.

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August 22, 1997

Long term TDS storage procedures

1. Palletize the main unit for indoor storage. A cargo container is appropriate for indoor/outdoor storage.

2. Avoid wide variations in temperature and high humidity. The preferred environment is clean and dry at 60˚ F ambient. If high humidity is unavoidable, 70˚ F is recommended. 3. All exposed unpainted metal surfaces are coated with a rust

preventive at the factory prior to shipment, however, check these surfaces periodically to be sure that no corrosion is taking place. The recommended rust preventive (slushing compound) for bare metal surfaces is Kendall Grade 5 (GE-D6C6A1) or equivalent.

4. Cover all openings to prevent water or dust from entering. Leave enough space around the drilling motor to allow the machine to breathe. Do not use silica gel or a dehydrating agent.

5. During storage, lubricant drains from the top half of the roller bearings in the motor, allowing corrosion to take place on the exposed areas. In order to counteract this, rotate the motor and gear train periodically to distribute lubricant over the top of the bearings. Perform this at three month intervals if stored indoors, and at one month intervals if stored outdoors. 6. The drilling motor is equipped with AC space heaters in

order to keep the internal motor temperature above ambient, preventing condensation. Connect power to the space heaters at terminals 1 and 2 in the AC motor J-box (see electrical schematic in the back of this section for proper voltage). Be sure to reseal the protective covering after connection. 7. Megger the drilling motor armature and field (static voltage of

1,000 VAC and 2 meg ohm minimum) when placed into storage and at three month intervals thereafter (one month if stored outside). Keep a record of the readings, as a drop between readings indicates an increase in moisture in the windings created by inadequate storage protection. If megger readings drop, bake the motor as soon as possible to restore proper resistance and avoid further damage.

8. Varco recommends adding one gallon of Mobilarma 524 Rust Preventive prior to shutdown. Or drain the oil and mix with a rust preventive, then replace the oil, run the oil pump and rotate motor to insure 100% coverage.

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Returning the TDS to service after storage

Before placing the TDS back into service, verify the following items:

1. Remove all rust preventive and any corrosion that may have taken place, taking special care with all load carrying components.

2. Follow the procedure in the drilling motor service manual included in this manual. To verify the condition of the motor, take note of the following:

a. Blow out all dust and dirt that may have accumulated in the windings with clean, dry air.

b. Visually inspect for spring corrosion, sticking brushes and general defects.

c. Remove the brushes from holders, inspect and replace them as necessary prior to operation.

d. Check the winding insulation continuity to ground with a 1000 volt megger. If the reading is less than two meg ohms, bake the winding until the moisture content is sufficiently reduced to produce an acceptable reading. 3. Perform a complete system test and adjustment as detailed in

the next section.

TDS Installation checklists (QA00026)

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reducing/pressure relieving valve to set the system along with a pilot to open check valve.

The IDS with onboard hydraulics uses a pressure reducing pressure relieving valve with a pilot to open check valve and a needle valve.

The IDS without onboard hydraulics uses a pressure reducing valve and a flow control valve.

The TDS DC System uses a pressure reducing valve along with a needle valve and pilot open check valve.

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Installation of Counterbalance System

Install counterbalance system as illustrated. When using chains use the following procedure to determine the chain length required.

a) Install Pear links onto hook-block

b) With the hook supporting the TDS, measure the distance from point of contact inside the pear link to top of the mounting lug on the integrated swivel bail.

c) Subtract 37/-14” from the measurement in step b. d) Cut the chain to length obtained in step c. The

tolerance is + 3-1/4” or – 0”

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Precharging the counterbalance

system

Please read these instructions completely before precharging, making note of the special cautions at the end of the section. 1. Use an inert gas such as Nitrogen for precharging

accumulators. If oil-pumped is not available, use dry, water-pumped Nitrogen gas.

2. Before precharging, make certain:

❏ The accumulator end caps are screwed flush into the accumulator body.

❏ The gas valve is screwed in tight.

❏ No oil remains trapped in the top end of the accumulator. 3. Remove the gas valve protector and the gas valve cap.

4. Attach the charging hose to the nitrogen bottle and to the gas valve using the following procedure:

a. Use thread sealing and lubricating compound on the pipe threads of the gauge.

b. Back the gas chuck stem completely out of the way before attaching the assembly to the accumulator gas valve. c. Use a wrench to tighten the gas chuck swivel nut onto the

gas valve. Close the bleeder valve.

d. Turn the gas chuck stem all of the way down, depressing the core in the accumulator gas valve.

e. Only crack open the nitrogen bottle valve to slowly fill the accumulator. Shut it off when the gauge indicates 900 psi. f. If the 900 psi pre-charge pressure is exceeded, make sure

the nitrogen bottle valve is closed, then open the bleeder valve (opposite gas valve below gauge) slightly, but only momentarily, to reduce pressure.

g. Before loosening the swivel nut, turn the gas chuck stem out all of the way, then open the bleeder valve.

h. Prevent the gas valve from turning, loosen swivel nut, and remove the assembly.

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Accumulators

The main task of an accumulator is to take a specific amount of fluid under pressure from the hydraulic system and store it until it is required within the system.

As the fluid is under pressure, accumulators are treated as pressure vessels and must be designed taking into account the max operating pressure. How ever they must also pass the acceptance standards in the country in which they are being used.

In order to store energy in accumulators, the fluid in an accumulator is weight or spring loaded or pressurised by gas. Therefore a balance is maintained between the pressure in a fluid and opposing pressure produced by the weight, spring or pressure created by gas.

In most hydraulic systems hydro-pneumatic (gas pressurised) accumulators with a separating element are used. Depending on the type of separating element used, accumulators are categorised into Bladder, Piston and membrane accumulators.

Function

Accumulators have to carry out various functions in a hydraulic

system:-Energy storage Fluid reserve

Emergency operation Balance in forces

Damping of mechanical shocks Damping of pressure shocks Compensation of oil leakage Damping of shocks and vibrations Damping suspension

Reclaiming of deceleration energy Maintaining constant pressure

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Pressure Relief Valve

Pressure relief valves are used in hydraulic systems to limit the system pressure to a specific set level. If this set level is reached the pressure relief valve is

activated and feeds the excess flow from system to tank

Theory of Operation

The basic principle of all pressure relief valves is that the inlet pressure is fed to a measuring surface which is acted on by force. The inlet pressure loads the poppet or lower side of the control spool with hydraulic force. The force of the pre-tensioned spring acts in the direction of the closure. The spring chamber is

unloaded to tank. As long as the spring force is larger than the pressure force, the seating element stays on its seat. If the pressure force exceeds the spring force the element pushes against the spring and opens the connection. The excess fluid returns to tank. As the fluid flows away via the pressure control valve, hydraulic energy is converted into heat

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Pilot Operated Check Valves

The pilot operated check valve positively locks a pressure load, but releases the load upon application of a pressure signal at the pilot port. This valve is normally used to lock an actuator in position when the directional control valve is centered. It it used in applications where overrunning load control and or a relief function is not needed or is provided by other means.

Theory of Operation

A pilot operated check valve consists of a valve body with inlet and outlet ports and a poppet held against a seat by a spring. Directly opposite the check valve poppet are a plunger and a plunger piston that are biased by a light spring. Pilot pressure is sensed at the plunger piston through the pilot port. The valve allows free flow from its inlet port to its outlet port. Fluid flow attempting to pass through the valve from the outlet port to the inlet forces the poppet to its seat, blocking flow through the valve. When enough pilot pressure is sensed at the plunger piston, the plunger moves and unseats the check valve allowing fluid to pass. The ratio of the load pressure to the pilot presure required to release the load is called the pilot ratio.

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Needle Valve

Needle valves are commonly used to meter accurate and precise flow of the fluid within a hydraulic

system. It can also be used to as a positive shut off for the hydraulic system.

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Reducing /Relieving Valve

These valves are dual purpose valves the Reducing part of the valve maintains pressure at steady flow rate while ensuring that the hydraulic system does not become over pressurised

activated and feeds the excess flow from system to tank.

The pressure reducing valves are used to influence the output pressure.

The reduction of input pressure or the maintenance of output pressure is achieved at set value, which is below the charging pressure available in the main circuit. It is thus possible to reduce the pressure in one part of the system to a level lower than system

pressure.

Theory of Operation

The basic principle of all pressure Reducing /Relieving valve is not to let the output pressure rise above a certain level, the relief valve monitors the pressure on the system, when the system pressure rises above a set pressure it returns the fluid back to tank. This pressure can be influenced by the relief port . (See hyd schematic)

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Set up Procedures

TDS DC System

The way to set up the TDS DC System is as follows:-e Check you have the following

tools:-9/16” Spanner and a 5/32” Allen Key

e Check you have the following drawings

available:-Drawing VM 2126 SHEETS 1 T0 5 Drawing 92114

Drawing 75420 Drawing 107530 Drawing 110407

e Check the following valves are correctly installed:-Pilot to open check valve P/N 77616

Needle Valve P/N 76419 Pressure Reducing Valve P/N 77615 Pressure Relief Valve P/N 94522-21N

e Check all connecting liks are secure and all bolts are safety wired.

e

Check TDS is not sitting on the guide stops .

e

Check the Hydraulic reservoir is full and all quick disconnects are installed properly.

e

Check all hose connections are tight.

e

Check the 2 accumulators are pre-charged with 900 psi of Nitrogen.

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Adjustment Procedure

Screw needle valve counterclockwise until fully open. Screw pressure reducing valve counterclockwise until fully open.

Start hydraulic power unit and let hydraulic oil flow for 2 minutes.

Bleed system cylinders.

Screw needle vale clockwise until fully closed. Screw pressure reducing valve clockwise until cylinders start to retract raising the TDS. Slowly screw the pressure reducing valve counterclockwise reducing the pressure to the cylinders.

When the swivel bail just contacts the hook note the pressure and decrease it by 25psi tighten lock nut.

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Troubleshooting the counterbalance

Symptom Probable cause Remedy

System does not hold pressure.

Needle valve is not closed. See adjustment procedure and check needle valve.

Cylinder rod seals leak. Replace seals.

Fittings or hoses leak. Tighten or replace as required. Dirty or defective PRV valve . See adjustment procedure.

Clean or replace.

Dirty or stuck check valve. Clean or replace. Counterbalance control valve

in rig down position.

Return valve to drilling position.

Cylinder rods remain retracted (closed).

Pressure setting too high. Adjust per adjustment procedure.

z

When activating or reactivating the counterbalance system, never start an empty system with the needle valve closed. Always start hydraulic unit first, run for 3-5 minutes, then slowly close needle valve with hydraulic unit running. If an empty system is started up with needle valve closed there is a good potential for damaging counterbalance cylinder seals.

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1) Where is the counterbalance manifold situated?

____________________________________

2) Name the three valves in the counterbalance manifold?

_______________________________________

3) What stops the counterbalance system from being over pressurized?

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4) Where are the Counterbalance Accumulators situated ?

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5) What type of valve is on the Counterbalance Accumulators ?

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6) What type of Accumulators are the Counterbalance Accumulators?

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7) What is the reason for having a counterbalance system ?

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9) Check the following drawings and mark up any defects missing parts.

___________________________________________________________

10) What tools are required to set up the counterbalance system?

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Training Manual

Alignment

Motor Alignment System

All Varco DC Top Drives have an Alignment System, One Top Drive System Model that differs from the other DC Models is the TDS 6S, and this is due the size and weight of that particular model.

Q What does the Alignment System do

A

The alignment cylinder is not intended to be used to align the pin

with the box at the well bore. It is a device to counterbalance the

offset weight of the DC motor and allow the system to accommodate

external forces. It is adjustable to ensure that the mainshaft is straight

at well center—to compensate for design tolerances in the guide rails and dolly. To work properly, the guide rails must be properly located,

and the dolly must fit within design tolerances..

Q What does the system consist of

A The earlier Top Drive systems (TDS 3)Models did not have a separate accumulator system, but all other models do have a separate accumulator for the system. The system with the separate accumulator consist of a duplex counterbalance cylinder with 2 flow control valves attached, hydraulic accumulator, hydraulic manifold with a pressure reducing cartridge valve a needle valve, and a pilot to open check valve.

Q Where is the system fitted

A The duplex cylinder is attached to a pad eye on the lower gear case and another pad eye attached to the motor guide frame.

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Training Manual

Adjusting the motor alignment cylinder

For units without a separate alignment cylinder accumulator

The counterbalance system must be properly adjusted before attempting to adjust the alignment cylinder.

Turn off the hydraulic power unit and bleed down the TDS accumulators by opening the needle valve located on the

counterbalance valve manifold. Remove the split shipping brace from the motor alignment cylinder, then open the two flow control valves by 1 ½ turns each these valve are located on the motor alignment cylinder supply and return lines. Close the needle valve and turn the hydraulic unit back on, then verify the pressure is 1100-psi +/- 100 psi.

Set a joint or stand in the rotary slips, (do not use a pup joint as this could give a false position). Bring the TDS down until it is stabbed into the box. The pin and box should be in alignment within +/ - ¼”. The OD of the pin should clear the shoulder of the box so that the connection can be made up without damaging the threads. If adjustments are necessary, use the following

procedure.

a) Measure how far and in what direction the pin has to move to line up the pin and box.

b) Turn off the hydraulic power unit and bleed down the system then loosen the lock tab and jam nut on the cylinder clevis. c) Using an open ended spanner (wrench),(do not use a pipe

wrench) on the cylinder rod flats screw the rod in the direction

required. ¾ turn on the rod results in the pin movement of ¼”.

Note

Alignment cylinder rod extension should be 2 3/8” +/ -1/8” Gland to rod threads when aligned properly.

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Training Manual

Alignment

For units with a separate alignment cylinder accumulator

Check you have a pre-charge of 900 psi in the accumulator The counterbalance system must be properly adjusted before attempting to adjust the alignment cylinder.

The pressure setting is adjusted by screwing the pressure reducing

valve in or out with a hex wrench (Figure 13). Screwing in the valve increases pressure and moves the saver sub toward the rails.

Backing out the pressure reducing valve reduces pressure and moves the saver sub away from the rails (see additional notes at the end of this procedure).

1. Verify the correct pressure setting using the following procedure:

a. With the power unit on, back down the pressure using the pressure reducing valve (PRV) until the saver sub begins to pivot away from the rails. Record this pressure. b. Slowly increase the pressure until the saver sub no longer moves closer to the rails as pressure increases. At this time, the cylinder should be in a “dead band” area.

c. Slowly increase the pressure until the saver sub begins to move toward the rails again. Record the pressure reading when this occurs.

d. To determine the correct pressure setting, add the average pressure readings from steps a and c above and divide by

two. The resulting pressure “dead band” provides equal pre-load in each direction – both toward and away from the rails. e. Record the pressure setting for future reference.

2. Set a joint of drill pipe in the slips.

3. Bring the top drive down as if stabbing the saver sub into the box. The pin and the box should be in alignment so that the O.D. of the pin clears the shoulder of the box. If adjustment is necessary, use the following procedure:

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Training Manual

a. Measure how far and in what direction (toward or away from the rails) the pin must move to line up with drill pipe box.

b. Turn off the hydraulic power unit and bleed down the alignment cylinder accumulator. This allows the motor alignment cylinder to relax and the motor to rotate on its trunnions, until the swivel contacts the motor frame. c. Loosen the lock tab and jam nut on the cylinder clevis. d. Use a wrench on the cylinder rod flats to screw the rod into or out of the clevis, in the same direction the saver sub pin is to be moved. A 1/4" of pin movement results from a 3/4 turn of the rod. The alignment cylinder rod extension should be 2-3/8" ± 1/8" gland to rod threads when the system is properly aligned.

e. Secure the jam nut and lock tab.

f. The nominal position of the two flow control valves is 1-1/2 turns off their seats. Should heavy drill pipe vibration be encountered, first attempt to control it with non-rotating stabilizers in the casing close to the surface. If motor movement becomes excessive due to continued vibration (more than 1/2" of cylinder stroke), the flow control valves may be closed to 3/4 turn off their seats. g. Tighten the lock nuts and replace the caps on all valve

stems.

If the alignment cylinder is removed for service, install the alignment cylinder replacement brace to support the motor housing assembly while continuing to operate the TDS. After reinstalling the alignment cylinder, use the three bleed holes(located along top of cylinder barrel) to remove air trapped in the cylinder.

Rail spacing and setback from the centerline of the well must be held within recommended tolerances in order to maintain vertical alignment of the TDS.

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Alignment Cylinder Lug (ref)

Pressure Reducing Valve

Needle Valve

Motor Frame (ref)

Alignment Cylinder Manifold Accumulator Bracket Gas Valve

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Motor Alignment

Cylinder

Motor Frame Dolly (Ref)

Split Shipping

Brace

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Troubleshooting the Motor

Alignment Cylinder

Symptom Probable cause Remedy

Alignment cylinder fails to move transmission at trunnion pivot points with recommended pressure setting.

Transmission trunnion pins will not pivot in dolly support brackets, from lack of lubrication.

Free trunnion pins as needed and lubricate area regularly.

Counterbalance system works

erratically or does not work at all.

Possible problem with system hydraulic components.

Chec k Troubleshooting the

Counterbalance section of this book.

Loss of nitrogen precharge in accumulators located in motor dolly upright frame.

Recharge accumulators as per the procedure in th e Counterbalance section of this book.

System does not hold pressure.

Needle valve is not closed. Se e Adjustment procedure.

Cylinder rod seals leak. Replace seals.

Fittings or hoses leak. Tighten or replace as required. Dirty or defective PRV valve . Clean or replace.

Saver sub on TDS does not align with drill pipe.

Alignment cylinder pressure too high or too low.

Se e Adjustment procedure.

Alignment cylinder rod adjustment too long or short.

Adjust according to procedure.

Rails not properly aligned with centerline of well.

Check to make sure that rotary is in center of floor and then check alignment of rails in relation to rotary.

Excessive motor movement.

Alignment cylinder fluid flow not adequately throttled.

Se e Adjustment procedure. Normal adjustment is 1 1/2 turns from full closed position on flow control valves. If there is excessive movement close to 3/4 turn from full closed position.

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Pilot Operated Check Valves

The pilot operated check valve positively locks a pressure load, but releases the load upon application of a pressure signal at the pilot port. This valve is normally used to lock an actuator in position when the directional control valve is centered. It it used in applications where overrunning load control and or a relief function is not needed or is provided by other means.

Theory of Operation

A pilot operated check valve consists of a valve body with inlet and outlet ports and a poppet held against a seat by a spring. Directly opposite the check valve poppet are a plunger and a plunger piston that are biased by a light spring. Pilot pressure is sensed at the plunger piston through the pilot port. The valve allows free flow from its inlet port to its outlet port. Fluid flow attempting to pass through the valve from the outlet port to the inlet forces the poppet to its seat, blocking flow through the valve. When enough pilot pressure is sensed at the plunger piston, the plunger moves and unseats the check valve allowing fluid to pass. The ratio of the load pressure to the pilot presure required to release the load is called the pilot ratio.

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Needle Valve

Needle valves are commonly used to meter accurate and precise flow of the fluid within a hydraulic

system. It can also be used to as a positive shut off for the hydraulic system.

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Reducing /Relieving Valve

These valves are dual purpose valves the Reducing part of the valve maintains pressure at steady flow rate while ensuring that the hydraulic system does not become over pressurised

activated and feeds the excess flow from system to tank.

The pressure reducing valves are used to influence the output pressure.

The reduction of input pressure or the maintenance of output pressure is achieved at set value, which is below the charging pressure available in the main circuit. It is thus possible to reduce the pressure in one part of the system to a level lower than system

pressure.

Theory of Operation

The basic principle of all pressure Reducing /Relieving valve is not to let the output pressure rise above a certain level, the relief valve monitors the pressure on the system, when the system pressure rises above a set pressure it returns the fluid back to tank. This pressure can be influenced by the relief port . (See hyd schematic)

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Cooling Systems

Varco has four types of cooling systems the customer can choose from to cool the Varco Top Drive Drilling Motor.

1. Closed Loop Cooling 2. Local Blower

3. Local blower with extended air intake 4. Remote blower

Q Why have so many different systems. A The main reason is that countries around

the world have their own underlying certifying authorities how govern their policies on certification. Many of these authorities have different rules governing specifications on electrical motors. Depending on where the drilling rig is going to operate will depend on what cooling system will be used.

A Rig working in the North Sea may only have 2 systems to choose from, a Remote Blower system or a Closed Loop cooling System.

A rig working in the Gulf of Mexico can have all 4 systems to choose from.

Before a Top drive is sold a survey should be carried out on the installation to check the Top Drive System components conforms to the particular area where it is going to work.

Q What is the best system

A Each system has its own unique

advantages and disadvantages, the following pages describe all four systems.

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Closed Loop System

The Close Loop Cooling System can use EXD OR UL

components to meet all world underlying Authorities, by using EXD or UL components the Top Drive with closed loop cooling can have classification to work any where in the world. The system should be capable of producing a CFM of 3200.

The closed Loop system consists of the following main parts :-20 HP Blower motor

Heat exchangers Air Flow Ducts Water detectors

Differential pressure switch Pressure switch

Temperature switch Expo purge system Water pumps Flow indicator

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Blower Motors

The blower motor is a dual shaft 20 HP AC, that is attached to the blower mount brake cover. The motors are EXD or Ul rated it is always best to check the name plate before installing.

The impellers are attached to each shaft end and are fixed by a taper lock mechanism.

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The Blower impellers are then incased in the ducting assembly. A 8 “ flex connects to the ducts on the GE 752 or EMD Drilling Motor. The Blower inlets are connected to the heat exchangers

. .