Control method for preventing deformation in quenching process of 9Cr18 thin-wall bearing ring

The technology of a thin-wall bearing and a control method is applied in the field of heat treatment to achieve the effects of reducing the amount of subsequent grinding, reducing the workload of grinding and improving the efficiency of grinding.

CN101775480AActive Publication Date: 2010-07-14LUOYANG BEARING RES INST CO LTD
3 Cites 15 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2010-07-14

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention relates to a control method for preventing deformation in the quenching process of a 9Cr18 thin-wall bearing ring. The method comprises the following steps of: firstly designing an upper die (1) and a lower die (3) which have symmetrical structures; before quenching, loading the 9Cr18 thin-wall bearing ring (2) into a 45KW box-type heating furnace for preheating, wherein the preheating temperature is 850 DEG C, and the preheating time is 30 min; shifting the 9Cr18 thin-wall bearing ring into a 50KW high-temperature box-type heating furnace for heating, wherein the heating temperature is 1070 DEG C, and the time for keeping the temperature is 5 min; taking the 9Cr18 thin-wall bearing ring out, and placing the 9Cr18 thin-wall bearing ring on the lower die of the quenching die; covering the upper die of the quenching die, and fixing the upper die, the 9Cr18 thin-wall bearing ring and the lower die as a whole to be placed in quenching oil for quenching; separating the upper die and the lower die 3 min after quenching, and taking out the 9Cr18 thin-wall bearing ring. The qualification rate of the bearing ring quenched by adopting the invention reaches 98 percent, and the economic benefit is remarkable.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention belongs to the technical field of heat treatment, in particular to a control method for preventing deformation of a 9Cr18 thin-walled bearing ring during quenching treatment. Background technique

[0002] 9Cr18 thin-walled bearing rings will undergo dimensional and shape changes due to thermal stress and tissue stress during heat treatment, especially after quenching, the inner and outer diameters of 9Cr18 thin-walled bearing rings will increase, and elliptical or taper deformation will easily occur.

[0003] Generally speaking, the specific volume of quenched martensite is larger than that of other structures, and the volume of workpieces after quenching will increase. Due to the asynchronous heating and cooling of various parts of the workpiece, a temperature gradient is formed, resulting in thermal stress and tissue stress. In addition, the strength of the workpiece is reduced in the hot state, and the superposition of stress often exc...

Examples

Embodiment Construction

[0014] combine figure 1 , the anti-deformation control method used in the quenching treatment of 9Cr18 thin-walled bearing rings in the present invention is to design a set of quenching molds first, and the quenching mold is composed of an upper mold 1 and a lower mold 3. The contact outer diameter D1 of the die or the lower die is 100.32% of the inner diameter of the 9Cr18 thin-walled bearing ring 2, the maximum outer diameter of the upper die or the lower die is greater than the outer diameter of the 9Cr18 thin-walled bearing ring, and the contact outer diameter of the upper die or the lower die The wall thickness of D1 is greater than the maximum wall thickness of the 9Cr18 thin-walled bearing ring, and the sum of the effective widths at the contact outer diameter D1 of the upper die and the lower die is less than the width of the 9Cr18 thin-walled bearing ring.

[0015] If the outer diameter of the 9Cr18 thin-walled bearing ring is Φ143.67mm, the inner diameter is Φ132.8mm...