CN1330779C - Heat treating trimming method for large-scale bearing ring - Google Patents

Abstract

The present invention relates to a heat treating trimming method for a large-scale bearing ring, which has the technical processes that a: in a hardening furnace, a ring is heated to 810-860 DEG C; after the heat of the ring is preserved for 50 to 120 minutes, the ring is taken out of the furnace to be cooled in coil to temperature of 120-150 DEG C; b: elliptical deformation quantity is detected by measurement appliances of a pipe ruler, etc. a ring of which the deformation quantity surpasses the standard of Q/WZ. J3731-2002 is trimmed in a qualified range in a method of internal stay trimming; after the ring is cooled to room temperature, a trimming tool is removed; e: the trimmed ring is put into a tempering furnace and is heated to 150-180 DEG C; heat is preserved for 3.5 to 4 hours to eliminate quenching and trimming stress; f: qualified products are delivered to the next process step. The present invention has the advantages that compared with the prior art, the present invention reduces a tempering, and thus, the present invention can reduce the cost and enhance the utilization rate of equipment.

Description

Heat Treatment Shaping Method for Large Bearing Ring

technical field

The invention belongs to the technical field of bearing heat treatment, in particular to a heat treatment shaping method for a large bearing ring.

Background technique

The existing large-scale bearing ring heat treatment process is quenching---measurement---shaping---top tempering---top unloading---tempering---delivery, which wastes cost and increases product production cycle , Reduce equipment utilization and other issues. At present, the bearing industry is recovering and the output is increasing. The existing technology cannot meet the growth needs and must be improved.

Contents of the invention

The object of the present invention is to provide a method for heat treatment and shaping of large bearing rings, which omits the process steps of top tempering, can reduce production costs, improve equipment utilization, and shorten production cycles.

The technical solution of the present invention is a heat treatment and shaping method for large bearing rings. The process flow of the method is: quenching---measurement---shaping---top unloading---tempering---delivery. The specific steps are:

a. In the RJX-75 or RJJ-180 quenching furnace, heat the ferrule to 810-860°C, keep it warm for 50-120 minutes, then take it out of the furnace for oil cooling, and cool it to 120-150°C;

b. Use a measuring tool such as a pipe ruler to detect the amount of ellipse deformation;

c. For ferrules whose ellipse deformation after quenching exceeds the standard Q/WZ.J3731-2002, use a shaping tool to shape the ellipse deformation to the qualified range with the inner support shaping method. The original process increases the anti-deformation by 70%, but now The process increases the anti-deformation amount by 150%;

d, cool to room temperature, remove the shaping tool;

e. Put the shaped ferrule into the tempering furnace, heat it to 150-180°C, and keep it warm for 3.5-4 hours to eliminate the quenching and shaping stress;

f. Move qualified products to the next process.

When the quenching temperature is 825°C and the tempering temperature is 175°C, the shaping effect is better.

The beneficial effect of the invention is that one tempering is reduced, the cost can be reduced, the utilization rate of equipment can be improved, the production cycle can be shortened, the production organization is beneficial, and the shaping is easier.

Detailed ways

The quenching furnace uses the RJX-75 furnace. Put 3 pieces of 23080CA inner rings into the furnace. The quenching temperature is 825°C. After holding for 84 minutes, it is oil-cooled. When it is cooled to 140°C, the deformation is detected to be 0.80mm. Use a jack to increase the anti-deformation amount by 1.2mm, cool to room temperature, remove the shaping tool, and then put the inner ring into the RJT-85 tempering furnace for tempering. The process is to keep the temperature at 175°C and leave the furnace after 4 hours of heat preservation. Measure the ellipse deformation as 0.20mm, meet the standard requirements. The standard requires that the deformation should not exceed 0.40mm. After shaping according to the original process, the average ellipse is 0.35mm, and the rework rate is 30%; after shaping according to the current process, the average ellipse is 0.20mm, and the rework rate is 5%.

Claims (2)

1, a kind of heat treating trimming method for large-scale bearing ring, it is characterized in that, the technical process of this method is: quench, and----shaping--is unloaded the top--tempering---pay in measurement, its concrete steps are: a, in quenching furnance, lasso is heated to 810-860 ℃, be incubated 50-120 minute, the oil cooling of coming out of the stove is cooled to 120-150 ℃;

B, use are measured apparatus and are detected the ovalizing deflection amount;

C, to the be above standard lasso of Q/WZ.J 3731-2002 of the back ovalizing deflection amount of quenching, with shaping tool with its ovalizing deflection amount with the shaping of inner support shaping method to acceptability limit;

D, be chilled to room temperature, remove shaping tool;

E, the lasso after the shaping is put into tempering stove, be heated to 150-180 ℃, be incubated 3.5-4 hour, eliminate and quench and shaping stress;

F, salable product are moved on to next procedure.

2, a kind of heat treating trimming method for large-scale bearing ring according to claim 1 is characterized in that, described quenching temperature is 825 ℃, and tempering temperature is 175 ℃.