Field Welding for Assembly or Repair The large size of Trucks & Loaders which are produced by Komatsu Mining Systems, Inc. often makes extensive field welding procedures necessary when machines are assembled after shipment. Repairs during normal mainte- nance may also require welding to prolong the useful life of components and reduce costs of operation. The field welding information contained here is general information and is not intended to give detailed instructions on specific repairs. The publications listed in the bibliography at the end of this document will give more specific details for most welding procedures.
For more specific information or details, contact the KMS Area Service Man- ager. WELDER QUALIFICATION AND TRAINING The welding technique must be of the highest standard to produce the soundest weld possible. Only welders who have been trained and qualified for structural steel welding in all positions, in conformance with the Ameri- can Welding Society (AWS) D1.1 or (AWS) D14.3 only, are allowed to perform the welding. The welding instructions for field assembly of KMS components are normally provided by engineering drawings. Additional detailed welding instructions for field repairs are pro- vided in the field repair manuals SEBD14001 and SEBD15002.
A full understanding of the AWS standard welding symbols is necessary to perform and inspect such field welds. Weld sizes specified on the drawings are intended to reflect minimum requirements. Always disconnect the positive and negative bat- tery cables of the vehicle before doing any welding on the unit. Failure to do so may seriously damage the battery and electrical equipment. If truck/loader is equipped with an electronically controlled transmission or engine, be certain to fol- low all disconnect procedures detailed in the man- ufacturer's and/or the truck/loader service manual.
WELD PROCESSES DO NOT DISCONNECT OR REMOVE any control circuit cards on electric drive trucks or any of the “AID” circuit control cards. Electric arc welding, either the semi-automatic “MIG” (GMAW), Flux Core (FCAW), or “Stick” electrode weld- ing (SMAW), are approved processes for field installa- tion and maintenance welding. Welding of highly stressed structural members such as castings, torque tubes, top and bottom plates on the frame rails, and the curved intersection points of frames should be done with the specific detailed instructions from KMS Prod- uct Service. See Annex A for repair procedures.
These repair procedures are detailed instructions for most high stressed structural members. Always fasten the welding machine ground lead to the piece being welded; grounding clamp must be attached as near as possible to the weld area. Never allow welding current to pass through ball bearings, roller bearings, suspensions, or hydrau- lic cylinders. Always avoid laying welding cables over or near the vehicle electrical harnesses. Welding voltage could be induced into the electrical harness and possibly cause damage to components. Approved Consumables Are: GMAW, ER70S-6; FCAW, E70T-5, E71T-8, E71T8-Ni1; and SMAW, E7018 or E8018.
FAM0403 930E FIELD ASSEMBLY MANUAL Page 4-1 Field Welding Procedures