CN105624390A - Heat treatment method of large thin-wall stainless steel bearing ring - Google Patents

Abstract

The invention discloses a heat treatment method of a large thin-wall stainless steel bearing ring. In the primary cold treatment of the stainless steel bearing ring, the temperature is in a range from -75 to -80 DEG C, and the insulation time is 2-2.5 h; in the secondary cold treatment, the temperature is in a range from -175 to -185 DEG C, and the insulation time is 4.5 h; the primary and secondary tempering temperature is 150-160 DEG C; and each tempering insulation time is 4-4.5 h. The method reasonably designs the tempering times, the cold treatment times, the cold treatment speed and time and the like. The method can solve the size stability in the grinding process, the size stability in the placing process and the size stability in the use process of a large thin-wall 9Cr18 steel bearing ring.

Description

The heat treating method of a kind of large thin-wall stainless steel shaft bearing ring

Technical field:

The present invention relates to a kind of bearing processing, the heat treating method of especially a kind of large thin-wall stainless steel shaft bearing ring.

Background technology:

Along with the progress of technology, the application of 9Cr18 stainless steel bearing is more and more wider, at sea and some have its erosion resistance in the environment of corrosion to be better than high-carbon chromium bearing, it is little that space installed by these bearings general, bearing accuracy height, the design of these bearings generally manufactures with 9Cr18 stainless steel, to meet erosion resistance, after the quenching of 9Cr18 stainless steel, residual austenite is many, in the mill course of processing, dimensional stability is difficult to ensure, in mill processing, class of precision is difficult to reach p4 class precision, and frequent processing more than 100 parts only can be chosen several products and reach accuracy requirement; In placement process, dimensional stability is difficult to ensure, and in use, dimensional stability is difficult to ensure, after the product that working accuracy is qualified places two months, dimensional precision at least declines a rank, and the qualified product that dispatches from the factory uses in two to three months class of precision seriously to decline, can not meet the requirement of equipment, often have customer complaint.

Summary of the invention:

In order to overcome above-mentioned deficiency, the present invention provides the heat treating method of a kind of large thin-wall stainless steel shaft bearing ring.

The technical solution adopted for the present invention to solve the technical problems:

A heat treating method for large thin-wall stainless steel shaft bearing ring, comprises the steps:

1) first time deepfreeze: stainless steel shaft bearing ring puts into deepfreeze case, and deepfreeze case cooling rate is 1.5 DEG C/minute, when temperature reaches-75��-80 DEG C, stops cooling, and is incubated 2��2.5h, take out lasso afterwards, naturally return to room temperature in atmosphere;

2) first time tempering: the stainless steel shaft bearing ring under room temperature state in step 1) is put into tempering stove, and tempering stove heat-up rate is 2 DEG C/minute, when tempering temperature reaches 150��160 DEG C, stop heating up, and it is incubated 4��4.5h, take out lasso afterwards, in atmosphere cool to room temperature;

3) second time deepfreeze: by step 2) in stainless steel shaft bearing ring under room temperature state again put into deepfreeze case, deepfreeze case cooling rate is 2 DEG C/minute, when temperature reaches-175��-185 DEG C, stop cooling, and it is incubated 4��4.5h, stopping insulation afterwards, bearing ring returns to room temperature in atmosphere naturally with deepfreeze case;

4) second time tempering: the stainless steel shaft bearing ring under room temperature state in step 3) is put into tempering stove again, and tempering stove heat-up rate is 2 DEG C/minute, when tempering temperature reaches 150��160 DEG C, stop heating up, and it is incubated 4��4.5h, take out lasso afterwards, in atmosphere cool to room temperature.

Described thin-wall stainless steel bearing ring material be 9Cr18, diameter is �� 250-�� 400mm, effective thickness 5mm-11mm.

Owing to adopting technical scheme as above, the present invention has following superiority:

The heat treating method of a kind of large thin-wall stainless steel shaft bearing ring of the present invention, has the following advantages:

1, the content of 9Cr18 stainless steel residual austenite can be effectively reduced, it is to increase working accuracy, the stability depositing size in process, and in use dimensional stability;

2, effectively improve the class of precision of product, increase the output value;

3, can effectively improve conforming product rate, reduce the labour intensity that workman picks, simultaneously cost-saving.

Accompanying drawing illustrates:

Fig. 1 is the process flow diagram of the present invention.

Embodiment:

Can explaining the present invention in more detail by embodiment below, the object of open the present invention is intended to protect all changes and improvements in the scope of the invention, and the present invention is not limited to the following examples;

Large-size stainless steel bearing ring after quenching, with correction holder together first time deepfreeze: deepfreeze temperature-80 DEG C, time 2h, deepfreeze cooling rate 1.5 DEG C/minute, arrives room temperature naturally in air after deepfreeze; First time tempering: tempering temperature 155 DEG C, time 4h, tempering heat-up rate 2 DEG C/minute, after tempering, sky is as cold as removal holder after room temperature. Second time deepfreeze: deepfreeze temperature is-180 DEG C, soaking time 4h, deepfreeze cooling rate 2 DEG C/minute, shut down with deepfreeze case to room temperature after deepfreeze to time; Second time tempering: tempering temperature 155 DEG C, tempering insulation time are that after 4h, tempering heat-up rate 2 DEG C/minute, tempering, sky is as cold as room temperature.

Carefully not stating part in above content is prior art, therefore does not run business into particular one and state.

Claims (2)

1. the heat treating method of a large thin-wall stainless steel shaft bearing ring, it is characterised in that: comprise the steps:

1) first time deepfreeze: stainless steel shaft bearing ring puts into deepfreeze case, and deepfreeze case cooling rate is 1.5 DEG C/minute, when temperature reaches-75��-80 DEG C, stops cooling, and is incubated 2��2.5h, take out lasso afterwards, naturally return to room temperature in atmosphere;

2) first time tempering: the stainless steel shaft bearing ring under room temperature state in step 1) is put into tempering stove, and tempering stove heat-up rate is 2 DEG C/minute, when tempering temperature reaches 150��160 DEG C, stop heating up, and it is incubated 4��4.5h, take out lasso afterwards, in atmosphere cool to room temperature;

3) second time deepfreeze: by step 2) in stainless steel shaft bearing ring under room temperature state again put into deepfreeze case, deepfreeze case cooling rate is 2 DEG C/minute, when temperature reaches-175��-185 DEG C, stop cooling, and it is incubated 4��4.5h, stopping insulation afterwards, bearing ring returns to room temperature in atmosphere naturally with deepfreeze case;

4) second time tempering: the stainless steel shaft bearing ring under room temperature state in step 3) is put into tempering stove again, and tempering stove heat-up rate is 2 DEG C/minute, when tempering temperature reaches 150��160 DEG C, stop heating up, and it is incubated 4��4.5h, take out lasso afterwards, in atmosphere cool to room temperature.

2. the heat treating method of a kind of large thin-wall stainless steel shaft bearing ring according to claim 1, it is characterised in that: described thin-wall stainless steel bearing ring material be 9Cr18, diameter is �� 250-�� 400mm, effective thickness 5mm-11mm.