Impact Crusher's Blow Bar

According to the information, the main damage form of blow bar is loose and broken, when the below bar loose or broken, it will cause to bolts broken and other blow bars, it will damage the rotor or the frame, sometime it will broke the rotor and main bearing . And blow bar cost very much, if we can find out the phenomenon of this reason, we can do better improvement and keep watch on this phenomenon. The flowing three points are the analysis why impact crusher’s jaw plate damage:

The quality of blow bar bolts. Due to the bad quality of bolts, they are often loose and break; this will cause the blow bar loose or interrupt. The fundamental reason is that, the model of small factory’s bolt has been used for many years; wear and tear becomes larger, so that the overall head bolts in poor contact use, and causing loose. Meanwhile, at the processing thread, sewing thread to make cooperation easier, it will be some thinning intentionally shaped teeth, thereby reducing the ability of fastening bolts.

The quality of blow bar itself. Blow bar is made of ZGMn13, look from the fracture, there are visible pores and even empty, this note presence of poor casting quality and heat treatment. this is the main reason for blow bars’ damage.

Incorrect operation and maintenance. For blow bars ’damage phenomenon when working, we visited SBM Company and learnt that , as it is difficult to exchange the blow bar, after the new blow bar installed on , should stop and check it whether there is any loose and tight it firmly.

According to above problem, they need to create the new bolts model, make the bolt head and the blow bar oval holes can be good contact with the contract surface. at the same time , control the thickness of the screw thread in the size tolerance ,thread finishing unloading machine groove, to prevent stress concentration and fracture.