2 Piece Forged Wheels Surface Hardness
2 Piece forged Wheels Surface hardness
2 forged wheels are commonly used as a mechanical device. In the wheel group, it is made of bearings, wheels and shaft combination. At the same time in the wheel group, the wheel is to support the entire lifting load of the body, and can be reciprocated on the crane movement. At the same time the wheels have to face hardening, wear and pitting and other phenomena.
Studies have shown that: under the conditions of online contact, the wheel surface hardness should not be lower than HE300, from the tread 10 to 12 mm at the hardness should not be lower than HB235. For trolley wheels, it is generally a wire contact. As the car track easy to find positive, better contact conditions, trolley wheels such as the use of surface hardening, hardened layer depth of 4 to 5 mm is feasible.
2 forged wheels in the point of contact conditions, to consider the wheel tread surface shear stress distribution gradient, then, should make the wheel tread hardness HB340 ~ 380; from the tread 10 to 12 mm at HB280 ~ 320; 15 ~ 18 mm HB260300; 19 ~ 24 mm at HB235. In this way, the life of the wheel is easy to guarantee. The use of forging the product process, and after a long casting, not only can be guaranteed quality, while using a longer time, while loading and unloading is also more convenient. In the driving round, quenching medium and tempering is its important processing technology, its characteristics are as follows:
Quenching medium: the use of water quenching is to improve the driving wheel round the most effective method, but the material water quenching the risk of cracking is particularly large, especially the outer edge to crack, so can not be used. Water quenching oil cooling method can also improve the surface hardness, but the workpiece edge of the smaller size, and the tread surface difference is large, quenching cooling time is inconsistent, poor water control time, is not easy to use, so you can use oil quenching, But to ensure that the workpiece as soon as possible after the oil into the oil quenching.
Tempering: driving large rounds with high temperature tempering, eliminating the work of a large number of residual stress, tempering tissue from low temperature tempered martensite, into a good comprehensive mechanical properties of high temperature tempered sorbite, so that High hardness at the same time to ensure that the workpiece has a good toughness, high temperature tempering stability of 550-580 degrees, 2-3 hours after the insulation in the air in the natural cooling.
In addition, there are many ways to travel large wheel processing, in the next day, we will continue to introduce for you!
The wheel group is a device used to support the crane and load and to reciprocate the crane in orbit. The main form of wheel damage is wear, hardened crushing and pitting. The material of the wheel is generally made of ZG430-640 steel. In order to improve the wear resistance of the wheel surface strength and life, tread should be surface heat treatment, requiring surface hardness of HB300-350, quenching depth of not less than 20mm.