J&M 220 Operating And Maintenance Manual - page 16

MODEL 220 

HYDRAULIC 

IMPACT HAMMER 

II. 

PREPARATION FOR OPERATION 

B.  SAFETY PRECAUTIONS (CONTINUED)

37. Rounded or damaged bolt heads or nuts should be replaced so that proper torque 

values may be obtained.  Proper torque values are necessary to prevent parts on 

this equipment, leads and crane boom from loosening and falling.  Refer to Torque 

Chart, in the manual, for proper values. 

38. Always be sure that the crane line is aligned with the centerline of the pile.  Do not 

side load crane boom or hammer.  Dangerous crane boom, or hammer, damage 

may result. 

39. Use tag line to control hammer whenever possible. 

40. When driving “batter” piles, insure that the leads, and crane boom, have sufficient 

bending strength to handle the worst case load.  Consult J&M. 

41. Do not attempt to service hydraulic accumulators without first venting all high 

pressure gas from these units. 

42. Pre-charge accumulators only to pressures specified, and only with Nitrogen gas. 

43. Pile ends must be cut square, and flat, before cushion material and/or drive cap are 

placed onto pile. 

44. Use only pile caps that are correctly sized for the type, cushion material and pile 

size being driven.  

45. Before starting driving operations, check that the hammer, striker block and pile cap 

are properly aligned with the centerline of the pile.  Dangerous lateral forces, 

generated by misalignment, may damage hammer or break piling, with resultant 

hazard from falling objects. 

46. Stay well clear of ram point, pile cap and striker block.  Fragments of metal may be 

broken, or spalled off, and ejected at high speed. 

47. Large amounts of heat are generated, within cushion material, during driving.  

Cushion material, or flammable materials in the vicinity, may ignite.  Personnel 

should use extreme caution, and avoid contact with ram point, cushion material and 

drive cap. 

48. It is the responsibility of the contractor to determine what, if any, hazardous 

materials, or gases, may be emitted from cushion materials due to deterioration, 

decomposition, excessive temperature or combustion.  Contact the cushion 

material manufacturer. 

49. Frequently inspect and tighten the wire ropes, wire rope clips and pins that secure 

the drive cap to the hammer.  Replace these components at the first sign of wear or 

fatigue.  Tighten clips regularly. 

REMEMBER, SAFETY IS EVERYONE’S BUSINESS. 

II-3