The Tighten Process Improvement Of The Engine Cylinder Head Bolt And The Reserch Of Torque Quality Control

Engine assembly process, almost all of the parts are made between one or more critical parts bolted together, is particularly important to the cylinder head and cylinder block, between the connecting rod and crankshaft, as well as between the crankshaft and cylinder block, etc. They are bolted together. Bolted removable connection is based on vision and creation, components can be connected together as running or moving like a part. Bolt connection must be able to resist external forces,so that has been assembled parts do not move in the direction of separation, which will cause loosening of bolted joints, damage or loss. And with the engine structure developed in depth, with closely fitting fasteners how to be more reliable, more stable has become the key engine performance.For a long engineering R & D personnel will be threaded coupling attention in its design, but how connected to the assembly process, ie selecting the right tools and assembly process has not paid much attention, so often did not reach the actual torque value drawing thread design requirements, or threaded coupling design unreasonable phenomenon. Due to the lack of tight threaded process research can not be resolved.We can only rely on the results of several experiments in the production process specified torque corresponding parameters. In this case, the validity of the threaded coupling design are greatly reduced, the quality of assembly can not be stable. To solve this problem, people have begun to pay attention screwed tight research process.In this paper, a new Caterpillar plant production line in Tianjin Co. need, first briefly introduce the basic theory of bolt tightening. The second chapter introduces the tightening methods and test methods torque, highlighting the torque- rotation of the principles and advantages, and focus by data Mechanism screwed, and collect relevant stations, and to illustrate a different method of tightening, Different engine bolt tightening quality and effectiveness achieved, thereby clearly tightened usingmulti-axis equipment, the use of torque- Advantages corner approach. The fourth chapter focuses on the coupling of dynamic torque bolt tightening and multi-axis control mode, the basic theory chapter before the fifth chapter describes the use of the cylinder head bolt tightening process improvement, and ultimately used in the production. In Chapter 6 describes the assembly line to build the engine torque Carter Tianjin factory quality control and management, starting from the point of view of prevention and control torque quality problems, the P-FMEA, CQMS management system, mistake proofing techniques were fused. Reviewed by FMEA tool to quantify the extent of the potential failure of key issues, so as to formulate the corresponding control of critical control points to solve the original control relying on experience and lead to problems is not comprehensive enough. Through this study, the 3500 series engines to solve problems often limit alarm monitoring torque during assembly,identified herein cylinder head bolt tightening process has been applied to the actual production, while improving the existing process results in a discrete bolt torque of larger issues, to ensure that the assembly quality of the engine. Make the product smooth operation.