MID/AN/12

Providing and fitting / Modification of 650 HP BHEL Make (HT Motor) including Replacement of bearing assemblies and fabrication of new Motor half couplings. Carriage of motor from the pump house Ranjan to workshop by suitable loading capacity load carrier for safe carriage/ transportation to workshop of the firm for modification and carriage of the same from workshop of the firm to lift irrigation station Ranjan .

Complete dis-assembling of motor which includes extraction of rotor out of stator. And then cleaning of the whole rotor recommended chemical cleaner of reputed make for proper insulation purpose. Complete Insulation of rotor with new “F” class insulation material such as glass, tape, mica tape, slot liner, glass tape, wedges of mica, etc., checking/soldering of all connection at both ends of the rotor and the connection connecting the rotor winding the rotor cable leads. Applying Becktol Red/Grey varnishing with class F Varnish of reputed make. Drying out the rotor at optimum controlled temperature as per standard practice and continuing the process till the standard max./reqd. IR Value and PI value is achieved. Complete job including the cost of material and labour charges.

Modification of 650 HP BHEL Make (HT Motor) by way of Straightening alignment settings of solid shaft 485 KW 6.6. KV. H.T. motor, re-metaling/ depositing of metal on worn out portion on N.D.E & D.E of rotor shaft using low heat electrode of reputed make followed by machining to true bearing size. Providing, fabrication, and fitting in position of sleeve into the enlarged bore followed by machining / polishing to achieve specified fit for outer cone of the DE bearing. The job includes dynamic balancing of the rotor after modification/strengthening of rotor on balancing machine for proper functioning of rotor to its maximum limit complete job.

Modification by way of strengthening of Complete 650 HP stator be VPI procedure. Checking of all the coils from the stator, checking out all the laminations after proper cleaning of core/ slots making it free from oil / grease/ other deposition and replacement of damaged wedges/appropriate preparation of the stator for impregnation. The slot portions are to be wedged at the ends, centre and magnetic putty is to be inserted with adequate pressure to enhance flux linkage. Complete Insulation of all coils with the new “F” class insulation material of high quality such glass fibre or polyester and mica impregnated or glued together with epoxy, polyester amide (polyamide or polyimide), polyurethane or other resins having superior thermal stability, glass tape, fine cotton tape, wedges of mica textile etc. insertion of packing/anti vibration blocks, wedges and locking the same properly. The coil ends must be rigidly supported and adequately braced with binding rings or tapes to prevent their movement and also absorb shocks and vibrations during excessive over-loads, starting inrush currents, and voltage surges. Insulation of all the 54 No. of coils connections after brazing with eutectic brazing rods (14% of silver brazing rods) by applying in layers of glass mica tape reinforced by the varnished glass sleeves. Insulating the connections of the stator coil and also cleaning connections connecting the complete stator with CRC 226/ lectera. Varnishing the stator with class F Epoxy gel/ varnish coat of reputed make and drying out at optimum controlled temp. as permissible in standard practice. Continuing the drying out process till the required IR Value is achieved. Providing/ fitting in position of stator connection leads of actual length and specification. Complete job including the cost of material, labour charges.

Fabrication, providing and fitting of heavy duty ERW flanged end shaft enclosing tube of 200mm. dia x 2000mm long, 6/8mm. thickness, having flanges on either side(welded on inside of the pipe) with drilled and thProviding and fitting of new bearings a) 6248/C3 Ball bearing b) 6228/C3 Ball bearing Complete job including the cost of material after deduction of rebate on old material/scrap hire charges for tools and tackles required during the execution of job and labour charges. readed 6 No. holes to suit M20 x 50mm bolts.

Cleaning of the top bearing oil chamber with flushing oil & providing and re-filling of fresh lubricating oil of actual specification up to the mark. Complete job.

Fabrication of the motor half coupling along with spacer and coupling bolts of mild steel material of proper grade and size as per sample available at LIS Ranjan.

Reassembling of 650 HP BHEL make solid shaft 6.6. KV, 485 KW HT Motor at site & shifting the assembled motor and placing on motor skirt. Coupling the motor with VT pump half coupling, restoration of all electrical connections of motor to LRS, motor panels and slip rings, making proper alignment of motor with pump and adjustment thereof. Testing the motor on load for all connected parameters and commissioning for proper operation. Complete job in all respects.

M/S RAGHUNATH MECHANICAL AND ELECTRICAL ENGINEERING WORKS

GS ENGG WORKS