Improve mobile jaw crusher jaw stiffness
Time: 2015-02-04
Jaw crusher moving jaw and fixed jaw broken when a huge bear crushing force and friction materials, relatively easy to wear, and moving jaw of life and the life of the relationship between productivity and jaw crusher.
Most of the movable jaw on the market in the course of the front-end products generally badly worn, hardness around 140HBW, did not meet the technical requirements of 152 ~ 207HBW, to solve the problem of moving the jaw insufficient hardness, to ensure the quality of jaw crusher, we decided to movable jaw test materials for the heat treatment process.
1. Determine the embodiment
I produced the movable jaw made of JEP0033, belong carbon low-alloy steel, due to the materials not previously produced products, processing technology and perfect detection means, the lack of experience in the mechanical properties of qualified under the premise has never been detected product hardness, heat treatment process has been by JEP0033 standards, now want to move jaw problems for performance analysis hardness.
(1) The material is a low-carbon low-alloy steel, especially in the chemical composition of the carbon content of its performance impact is more obvious, the chemical composition of the casting is not easy to control, only the use of normalizing, tempering process in order to achieve hardness.
(2) the use of quenching process, due to the presence of cracks and other defects in castings foundry, to the corner of the magnetic particle inspection, ultrasonic testing machined surface was found to repair the defect, in order to carry out non-destructive testing of qualified after quenching, if flawed, in subsequent quenching process has the risk of cracking.
2, the test program to determine
(1) pouring a sample: Casting 30mmx200mm test bar 10, if successfully tested on the movable jaw for process testing.
(2) determine the material composition, casting provide each movable jaw chemical composition.
(3) non-destructive testing, magnetic particle moving jaw at the corner detection, machined surface ultrasonic testing, issue a report, if there is defect repair, non-destructive testing after passing the subsequent heat treatment.
(4) heat treatment process, first test bars for process test to determine the hardness after quenching JEP0033 as a reference to the use of the movable jaw, be adjusted according to the actual situation of the tempering temperature.
(5) hardness testing, hardness testing of test rods, after normalizing swap and quality test pieces were hardness testing.
(6) the mechanical properties of the test, the same test bars furnace mechanical properties test.
(7) crossed the workshop is responsible for moving the jaw after heat treatment were crossed, determine deformation.
3, the test track implementation process
(1) test bar quenching and hardness testing on two test bars were quenched, the main purpose is to determine JEP0033 material hardenability, which is made of low carbon steel, hardened bad, if you can not reach the hardness test rod 152 ~ 207HBW, movable jaw less likely to reach the hardness.
Quenched hardness after detection of about 180HBW, explain properly adjusting the process parameters, the hardness of the movable jaw can also meet the technical requirements.
(2) the use of quenching process, due to the presence of cracks and other defects in castings foundry, to the corner of the magnetic particle inspection, ultrasonic testing machined surface was found to repair the defect, in order to carry out non-destructive testing of qualified after quenching, if flawed, in subsequent quenching process has the risk of cracking. Upon examination, the movable jaw NDT qualified, after quenching hardness can reach 152 ~ 307HBW.