Under normal circumstances, the diesel engine crankshaft is made of high-quality steel, or high-quality alloy steel as raw material, after forging process. And its journal after finishing, and the use of excellent heat treatment process and nitrocarburizing, diesel engine crankshaft journal surface with high wear-resistant layer and fatigue layer. As a result, crankshaft neck fatigue resistance than the conventional treatment of crankshaft journals increased by 40%.
Because of this, in the process of using the diesel engine crankshaft, if it is found that the journal is worn, or there is a need for repair of a burned bearing accident, then a more special repair method is required for the treatment, rather than a simple grinding . The correct approach is to send the crankshaft to a dedicated factory, first grinding, and then re-nitriding and dynamic balancing test.
Only in this way can give full play to the good performance of diesel engine crankshaft. It should be noted that the crankshaft delivery factory repair process, the user can first remove the spare crankshaft for use, until after repair storage as a backup crankshaft storage. Remember, in the process of replacement, should take into account the crankshaft of each model is universal problem.
Generally after the diesel engine crankshaft grinding process, but also must be the corresponding heat treatment, which is why? This is because the product is a one-piece design, full support forging molding structure. Therefore, after forming the forging die, each journal undergoes a surface nitrocarburizing heat treatment after the refining process, and the depth of the nitride layer reaches 0.15 to 0.20 mm.
In the process of carrying out this process, the temperature conditions are usually low, so the deformation of the diesel engine crankshaft is relatively small. In comparison, after this treatment, not only can enhance the surface hardness of diesel engine crankshaft, but also give it more powerful wear resistance. Especially improve the surface fatigue strength, better service in high-strength diesel engine, while ensuring the accuracy of the crankshaft.