Working conditions and material and heat treatment requirements
1. Condition: spring with simple shape, small section and little force
Requirements: 65 785-815 ℃ oil quenching, 300 ℃, 400 ℃, 500 ℃. Tempering at 600 ℃, corresponding hardness hb512, hb430, hb369, 75780-800 ℃ oil or water quenching, 400-420 ℃ tempering, hrc42-48
2. Condition: medium load large spring
Requirements: 60si2mna65mn oil quenching at 870 ℃, tempering at 460 ℃, hrc40-45 (65Mn quenching and tempering hb280-370 for agricultural machinery seat spring)
3. Conditions: heavy load, high spring, large leaf spring and spiral spring with high fatigue limit
Requirements: 50CrVA, 60simna, oil quenching at 860 ℃, tempering at 475 ℃, hrc40-45
4. Condition: coil spring with diameter of 8-10 mm working under multiple alternating load
Requirements: 50crmna840-870 ℃ oil quenching, 450-480 ℃ tempering, hb387-418
5. Conditions: locomotive, rolling stock, coal water locomotive or plate spring
Requirements: 55simn, 60Si2Mn hrc39-45 (hb363-432) (Jiefang automobile leaf spring: 55si2mn hb363-441)
6. Conditions: coil spring of vehicle and buffer, tension spring of automobile
Requirements: 55si2mn, 60Si2Mn, 60si2cra quenching, tempering, hrc40-47 or hb370-441
Conditions: plunger spring of diesel pump, spring of fuel injection nozzle, valve spring of agricultural diesel engine, valve spring and plate spring of medium and heavy duty vehicles
Requirements: 50CrVA quenching, tempering, hrc40-47
8. Conditions: coil spring and flat spring working under high temperature steam, water pipe spring and seawater erosion resistant spring, Φ 10-25mm
Requirements: 3cr13hrc39-46 4Cr13 hrc48-50 hrc48-49 hrc47-49 hrc37-40 hrc31-35 hrc33-47
9. Condition: spring working in acid-base medium
Requirements: 2cr18ni91100-1150 ℃ water quenching, stress relief after winding, tempering at 400 ℃ for 60min, hb160-200
10. Condition: elastic retaining ring δ 4, Φ 85
Requirements: 60Si2 preheating at 400 ℃, oil quenching at 860 ℃, tempering at 430 ℃ and air cooling, hrc40-45