The comparison of good quality and lower quality rollers
The market of undercarriage parts is confusion these two years. The price is quite different with same part. Maybe you will not know how to choose your products. There are some details to show you the difference between good quality and lower quality. Taking track roller of PC200 for example.In the market, there are different price for track roller of PC200---USD $30 up to $86.
Track roller is made up of roller body, bushing, floating seals, collar, shaft, etc. So they effect the price.
Heat treatment and material of roller body:
A. For OEM, high quality parts which is popularly used in mining(unit weight around 38 kgs)
Material of roller body is 40Mn2 round steel. Complete conditioning heat treatment and the rail surface intermediate frequency processing. Surface hardness is 58-62 HRC, depth 20-30mm. Good abrasion resistance and enough bearing capacity
B. Medial quality parts (unit weight around 35 kgs ) The material is 50Mn square steel, intermediate frequency processing. Surface hardness is 50-55 HRC, depth more than 10mm which is shallower.
C. Low quality parts, unit weight around 32 kgs.
The material is 50Mn square billet. Intermediate frequency processing, surface hardness is around 50 HRC. Bad bearing capacity. The key is that the rail is smaller and with less lubricated oil. Cheaper cost to save profits.
Roller shaft/pin : 40Cr used in mining, Intermediate frequency processing after heat treatment. Roughness of surface is around 0.8mm. For lower quality parts, they use 45# steel without heat treatment. The roughness of surface is around 0.6mm. The depth is not enough then the good quality parts which is easy to make bushing broken.
The thickness of copper is 0.7-1mm for the good quality with material Cu10-10. And for lower quality parts, the thickness of copper is 0.2-0.4mm with material Cu6-6-3. Besides, length of bushing for lower quality parts is shorter(50&60) which the lifespan will be cut down,
Floating seals: the material for good quality parts is 15Cr3Mo whose life span is more than 6000 hours. And for lower quality parts, it is 12Cr1Mo whose life span is around 3000 hours.