Belt Bucket Elevator Design

By

N.Saravanan,

Grinding Technology Department,

FLSmidth Pvt Ltd.,

Purpose of bucket elevators

* Bucket elevators are used to lift bulk material from

one height to another.

* Bucket elevators are an ideal solution for

vertical transportation

* At the bottom, the buckets pick up product fed into the elevator boot and at the top the product is discharged as the bucket turns downward over head pulley.

* Along with each type of elevator, different styles of buckets have been developed which better suit the elevator or the materials to be handled.

Types of bucket elevators

Centrifugal discharge elevator (CE) :

This is the most commonly used type with bucket mounted on belt or chain for handling of

free flowing or small particle

Continuous discharge elevators (CO) :

This type pf elevators are used for handling

large lumps and material

Positive discharge elevators (PO) :

This is similar to centrifugal type except the bucket are

end mounted

BELT BUCKET ELEVATOR INTRODUCION

Bucket elevator belts and conveyor belts have different requirements.

 For elevator service, you need to calculate

the strength of the belt needed to

 In addition, you need to calculate the strength needed to handle the available horsepower. This is easy to accomplish. Since the weight of the buckets is essentially the same on both sides of the leg, the weight of the material is the difference.

Standard Elevator Bucket Punching

 The

type, size, weight, capacity, spacing, and projection of the buckets

Important advantages of belt bucket over chain bucket elevators

* Lower wear and tear * Quiet operation

* Higher specific conveying capacity * Lower power consumption

TECHNICAL SPECIFICATION

Equipment : Belt Bucket elevator Material to be handled : Raw meal

Bulk density : 0.8 to 0.9 T/M3

Material Temperature : Max. 120 0 _C

Capacity (Design) : 350 T/hr C/C Distance : 68.570 Mtrs

Belt : Steel Chord Belt 1050 mm width Belt strength : 2000 kp/cm

Belt speed : 1.66 m/sec. Bucket size : 900*335*5

TECHNICAL SPECIFICATION

TECHNICAL SPECIFICATION

BOLT SIZE Torque M 20 * 1.5 64 Nm/Bolt M 24 * 2 1000 Nm/Bolt M 30 * 2 2200 Nm/Bolt

DRIVES

Auxiliary drive : Geared motor- Greaves make GM 095, 5.5 KW, 56 output RPM with spiral Jaw coupling

Make : MARK AEC

Safety Device : Belt sway switch 220 V, 400 mA Electronic speed regulator

Painting : 2 coats of primer after Sand blasting and 1 coat of final finish synthetic enamel paint by spray painting.

Material of construction

Buckets : 5 mm thick plate – IS:2062 Head Casing : 10 mm thick plate - IS:2062 Boot Casing : 16 mm thick plate - IS:2062 Intermediate Casing : 5 mm thick plate - IS:2062

SPARE PARTS LIST

S.No Item Qty per assly

01 Buckets 306 Nos

02 Head shaft Bearing 2 Nos 03 Boot shaft Bearing 2 Nos

04 Belt 1 Length

05 Clamping device 1 Set

06 Bucket fixing bolt 2142 Nos 07 Tension Device Assly/ Bearing Bush 2 Nos

CONSTRUCTION DETAILS

* Head casing

* Lower head section * Head shaft assembly * Boot casing

* Boot shaft assembly * special steel chord belt * Belt guide rollers

* Buckets

* Safety devices

* Intermediate casing

* Main drive ( Bevel Helical Gear box & Fluid coupling ) * Auxiliary drive

* Maintenance platforms * Flanged inlet opening

Erection

* Fastening the side frame to the platform * Drive unit tied into elevator casing

* Mounting of elevator belt * Mounting the buckets

Operational procedure

The following check points should be reviewed before initial operation.

* Head and boot shafts must be parallel to each other and pulleys in line * Casing plumb to within given tolerances

* All bolts joining sections properly tightened * Reducer filled with oil to proper level

* Correct motor rotation

* Tighten all bucket moving bolts

* All lateral supports in place and secured * Bearing lubrication

* Guards should be provided

* Inspection door should be closed

Initial operation

Particular attention should be directed to the following * Loud or unusual noise

* Excess vibration * Bearing overheating * Drive unit overheating

MAJOR COMPONENTS MAINTENANCE CHECK

LIST

S.No Item Check point Frequency

01 DRIVE UNITS Motor Gear Box Coupling Geared motor Level switch Lubricants, Heat-up Lubricants, Heat-up Alignment & Tightness of bolts Lubricants, Heat-up Electrical function As per Manufactures Manuals

MAJOR COMPONENTS MAINTENANCE CHECK

LIST

S.No Item Check point Frequency

02 Head casing

Baffle plate Pillow Block in Head Shaft

Assembly

Shaft assembly

Wear out Position/ Fit out condition Grease in bearing General cleaning & Check for worn out of parts & replace if Required.

Check for worn out parts

Monthly

Every 3 months Every 2 years

MAJOR COMPONENTS MAINTENANCE CHECK

LIST

S.No Item Check point Frequency

03 Take up Tension in screw rods

Every 3 months

04 Inspection hole at boot casing Material accumulation during break down Foreign material in feed. Weekly once

MAJOR COMPONENTS MAINTENANCE CHECK

LIST

S.No Item Check point Frequency

05 STUFFING BOX

Inspection of packing for wear & tear Tightness of glands screws

Monthly

06 BELT & BUCKETS

Tightness of Bolts & Nuts on Buckets

Inspection of belt for damage Inspection of bolts & tightness &

completeness

Deformed and damaged buckets to be replaced

First 100 hours of operation Every 3 months

MAJOR COMPONENTS MAINTENANCE CHECK

LIST

S.No Item Check point Frequency

07 Clamping Device

Tightness of bolts with torque wrench After 50 hours of operation After another 2 weeks After another 6 weeks After another 3 months

LUBRICATION CHART

Qty Frequency Method of application 01 Antifriction bearings in Plummer block Grease Servogem 2 of Indian oil 20 Gms 800 hours/ as and when required By Grease Gun/ By hand

02 Motor Grease Servogem 3 20 Gms Every year 10000 running hours Grease Gun

03 Gear box Lubricati ng oil Servomesh SP 320 of Indian oil 100 Ltrs 6 Months By pouring through oil plug

04 Fluid coupling Lubricati ng oil

As per Manufacture’s Manuals 05 Geared motor Lubricati

Troubleshooting

Please see the “ Troubleshooting.doc “ file for various troubleshooting

methods.

HEAD PULLEY & BOOT CAGE

INCHING DEVICE

This is normally a low speed geared motor. It permits low speed drive for inching and turning of large size and high speed bucket elevators in case of maintenance, inspection and test run

Jaw clutch

Advantages of Fluidomat Fluid Couplings:

 Wear-free power transmission because of absence of mechanical connection between the input and output elements.

 No-load start-up of motor irrespective of machine load. Motor peak torque utilized for machine acceleration.

 Motor selection to operating HP rather than starting loads. Saving on energy cost and capital cost.

 Simple control of maximum or limiting torque by easy variation of oil filling.

 Added protection for motor and driven machine by limiting torque to a predetermined safe value.

 Automatic unloading of prime mover in case of any sustained overload, by blowing-off of fusible plug on coupling, thus draining out oil.

Advantages of Fluidomat Fluid Couplings:

* Automatic synchronization and load sharing in case of multi-motor drives

* Effective dampening of shocks, load fluctuations and torsional vibrations. Helpful in improving the drive duty conditions in machines subjected to shock loads, frequent load changes, startups and reversals.

* Smooth and controlled acceleration of driven machines. Important for machines such as conveyors, wire drawing and textile machines.

* Step less speed variation in wide range obtained in scoop type fluid couplings. * Continuous clutching and declutching of large drives obtained from SC type couplings.

* Economy on machine and drive designs. * Energy saving