TM 5-3895-374-24-1 Disassembling Gear Reducers General The    following    information    is    a    general    guide-line    for    the disassembly  of  a  typical  EURODRIVE  reducer.  If  additional information is needed, call our office and have the information contained on the reducer’s nameplate available. On  the  reducer’s  nameplate,  under  "Type’,  a  code  of  several digits will be embossed. The first digit (either an R, S, K, or F) establishes the type of reducer Typical cross sections of the four EURODRIVE reducer types are shown on page 20 Some types and sizes are quite different than the ones shown on  page  20    For  this  reason,  a  Spare  Part  List  should  be obtained for proper identification of parts prior to disassembly The  Spare  Part  Lists  do  not  bear  any  part  numbers  for  the gears,  since  these  will  vary  for  different  ratios  EURODRIVE gears   have   embossed   numbers   for   positive    identification. When  ordering  replacement  gears,  please  have  this  number ready. Certain reducer parts will be destroyed during the disassembling process Replacement parts should be on hand before starting the disassembly These items generally include gaskets, seal rings, bearing caps,  nilos  rings  and  oil  slingers. A set of shims is needed if gears are to be replaced. Bearings  used  are  standard  sizes,  their  international  code  is shown on our Spare Parts Lists. Helical Reducers Type ’R...","F..." Drain oil and remove input and output cover assemblies. ’RX " and  ’FA.."  type  reducers  do  not  have  any  output  covers  The ’FA " reducer has a square coverplate instead. All shafts, gears and bearings can be removed from the main body of the reducer after the circlips are removed. Some  shafts  have  to  be  pressed  out  of  the  gearhubs.  To  do so,  on  some  gears  supports  have  to  be  placed  between  the gears    and    the    casting,    to    keep    the    gears    aligned    in    a horizontal position during the pressing action Assemble the reducer in reverse order, placing shims between bearings and circlips to eliminate endplay. If the input pinion has been removed from its shaft (motor shaft or input shaft) the shaft and the pinion have  to  be  cleaned  of any grease Apply a few drops of "Loctite RC/609" on the shaft before remounting the pre-heated pinion gear On  the  assembled  reducer,  with  the   cover(s)   removed,   the embossed   identification   numbers   should   be   visible   on   the gears. Gaskets   should   be   set   in   liquid   seal   (Permatex)   to   ensure tightness. Reducers of the latest design (R .2,3, K .6) have no gaskets  on  the  output  housings  or  bearing  flanges      Loctite 574 has to be applied in all areas. Worm Gear Reducers Type "S.." Proceed  as  with  type  "R  -  and  "F  "  reducers,  with  following additional considerations: On  "S  "  type  reducers,  footmounted   style,   the   output   shaft must be removed to enable the removal of the remaining gears. Removal of the output shaft: After the seals, circlips, shims and bearing caps are removed, the  gearbox  must  be  placed  under  a  press,  with  the  output shaft    pointing    downwards    Place    keystock    of    appropriate dimensions inside the reducer, below the wormwheel, to keep the  shaft/wormwheel  assembly  in  the  centre  of  the  reducer, while  the  shaft  is  being  pressed  out  Failure  to  support  the worm wheel may damage the worm gear. On flange-mounted and hollow shaft reducers type ·SF  " and 'SA   " these procedures are not needed, since the output shaft can be taken out of the housing together with the worm wheel. Worm gear adjustment: The worm wheel has to be centred on top of the worm gear, when    assembling    the    drive    in    order    to    ensure    proper lubrication, and achievement of full nominal service life of the gears. For  this  purpose,  shims  are  provided  on  both  sides  of  the worm  wheel  bearings  Fig  7  The  location  of  the  contact  area between worm gear and worm wheel bearings. Fig.7: The location of the contact area between worm gear and worm wheel. Proper  shimming  can  be  checked  by  applying  a  thin  coat  of dark grease (Molykote) onto the worm wheel and running the greased  portion  several  times  through  the  gear  mesh.  The gear  contact  will  leave  an  imprint  on  the  grease  film.  This imprint should be centred at the middle of the worm wheel, or slightly offset in the direction of the worm gears rotation. See Fig.7 This offset will ensure better oil penetration into the gear mesh. Bevel Gear Reducers Type "K ..." There  are  special  instructions  available  for  the  disassembly and assembly of these reducers Please call our office for more information. (page 3-616)