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A

1. Problem Description: Erection of ESP inlet gate as per drawing at Hindalco Mahan Site.2. Present Method : In unit 1 , ESP inlet gate was erected as per the drawing no 3-57-999-008837 (Key

Plan and test data sheet ). Doing this the gate actuator comes outward to the boiler axis. But then there

is no access platform for the actuation and commissioning of the gate actuator available as per drawing.3. Proposed Method: This problem can be solved by interchanging the ESP inlet gates i.e erecting RHS

gate to left side and vice versa. Doing this the actuator automatically will come towards the platform

side.

4. Improvement: Doing this, no change in platform structure is required.

B

1. Problem Description: Pilferage problem with coal sampling material supplied.2. Present Method : At Hindalco Mahan site, the coal sampling material supplied are made of brass. Theitem includes aspirating fittings, cyclone collector etc. Total 32 nos of aspirating fitting are supplied for

coal pipes. The material is supplied from BHEL- Varanasi unit .These fittings are to be fixed in coal

pipes at the time of clean air test / and during coal firing. These fittings have one threaded end, which

again become problem to site as it is difficult to make internal threads in coal pipes. So another mating

fitting is to be arranged locally at site for using these supplied aspirating fittings. Also there are full

chances of theft of these fittings as these are temporary fastened with coal pipes.

3. Proposed Method: These aspirating fittings should not be made up of brass. Some other materialweldable with the coal pipes must be used for making these aspirating fittings.

4. Improvement: This will reduce the pilferage losses at site.C

Problem Description : Failure of copper tubes during bending supplied for air cylinder assembly of Hot PA

Gate/Cold PA Gate.

Present Method :As per drawing of Hot PA Gate and Cold PA Gate, for the actuation of gate, air cylinder

assembly is given. Instrument air is used for this purpose. Tubing work of this assembly is to be done using

copper tube which is supplied in running meter. As per drawing these tubes are to be bend and routed at

site. But during its bending crack formation in copper tube was observed, from which leakages took placed

during gate operation .

Proposed Method: For routing of the copper tubes, male-female connectors must be supplied from unit .This includes elbows /Tees /Unions etc.

Improvement: This will save tube bending time and also eliminate chances of any leakages.

D

1. Problem Description: Damage of motor bearing temperature gauges during motor transportation/handling at site.

2. Present Method : All fans/mills motors are supplied with bearing temperature gauges at their both driveand non-drive end side. It is observed that these gauges usually gets damaged during improper

handling at transportation to site .3. Proposed Method: To prevent these gauges, some box canopy should be incorporated.

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4. Improvement: Damages during handling can be avoided is these gauges are given inside some bobcover/canopy.

E

1. Problem Description: Bending of mill sole plates at site .2. Present Method : At present , mill sole plates are stored /kept at sites one over the other. Due to this

during erection and alignment of these sole plate its is found bends and for its alignment shims are

given which is usually not advisable .

3. Proposed Method: Actually keeping sole plates one over the other, the sleeves of sole plate acts aspoint load which is the main cause of sole plates welding . so in stores care must be taken that proper

wooden packers must be given between two sole plates or if there is no space constraints then these

should be placed separately.

4. Improvement: This will reduces bending cases of sole plate at site.F

1. Problem Description: Damage of Seal air fan coupling during early startup of fan.2. Present Method : There are two seal air fans given for 150 MW project. These are provided with auto

damper assembly . During the changeover of fans , the damper flap changes automatically. It is

observed during operation that there is some leakage from damper side due to which some air leaks to

the non-running fan and rotate it in opposite direction . When switching of fan takes place during this

period due to reverse torque coupling fails just at the start up.

3. Proposed Method: During switching care must be taken that the non running fan should be brought toozero speed and it should be started Also damper flap should be designed such like that no leakage take

place.

4. Improvement: Taking care during switching will save such coupling failures.G

1. Problem Description: Rusting inside mill gear box.2. Present Method : In 150 MW, the mill gear box lube oil is filled inside the gear box itself. It is observed

that gear boxes received at site are rusted from inside. Since very small hole is provided for gear box

cleaning so it was very difficult to clean it completely. Due to this ,differential pressure was not coming

correct across mill lube oil filter. It was going above limit and mill got tripped.

3. Proposed Method: The inside of gear box should be properly coated with anti-rust so that theseproblem can be avoided in future. Also at site store, gearboxes should be covered with tarpaulin so that

there should be no chance of water rain water seepage.

4. Improvement: This will save gearbox cleaning time. At present it takes 02 days for cleaning.Also filtercleaning activity will also reduce.

H

1. Problem Description: Problem in tracing and Identification of smaller items at BHEL site stores.2. Present Method : At BHEL-Hindalco Mahan Site stores, sometimes it becomes difficult to trace and

identify smaller size items like fasteners, instrumentation connectors etc. , as these items aredispatched in big wooden boxes. .

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3. Proposed Method: Rack system or Bin system should be used for storing of such items. This will notonly save searching time but will also reduce pilferage loss.

4. Improvement: This will systemize the store procedure of storing smaller items.I

1. Problem Description:2. Present Method :3. Proposed Method:4. Improvement: