1.彈簧的材料與技術(shù)要求
彈簧的材料為50CrVA鋼,技術(shù)要求硬度HRC45-49;在規(guī)定的負(fù)荷內(nèi)壓縮彈簧的長(zhǎng)度變化應(yīng)符合要求。螺旋壓縮彈簧加工工藝流程為:卷簧→再結(jié)晶退火→切斷、修正→淬火→回火→拋光→磨端面→校正→低溫去應(yīng)力→成品。
2.螺旋壓縮彈簧的熱處理工藝
(1)再結(jié)晶退火
彈簧卷制成型后,必須進(jìn)行再結(jié)晶退火處理,使彈簧幾何尺寸穩(wěn)定,減少淬火時(shí)的變形。再結(jié)晶退火溫度為550—650℃,保溫1—1.5h后空冷。少量可在鹽浴爐中進(jìn)行,大批量采用連續(xù)式電阻爐通控制氣氛。
(2)淬火
在鹽浴爐淬火加熱時(shí),應(yīng)將彈簧用鐵絲均勻地捆扎好,或?qū)椈商自谛景羯霞訜。加熱時(shí)要彈簧表面五氧化與脫碳。鹽浴應(yīng)經(jīng)過(guò)仔細(xì)脫氧。也可在可控氣氛的箱式爐中加熱,加熱溫度為850℃±10℃,保溫10—15min,出爐淬油冷透。
(3)回火
淬火后回火可進(jìn)行兩次。行矯正回火,矯正回火溫度一般應(yīng)低于終回火溫度20℃左右,保溫10—15min,出爐空冷。然后進(jìn)行終回火,在彈簧尺寸矯正后,將彈簧裝在回火定型夾具上進(jìn)行終回火;鼗鸲ㄐ蛫A具應(yīng)彈簧的螺距和自由長(zhǎng)度符合要求;鼗饻囟葹420℃±10℃,保溫30—35min,出爐水冷。
(4)拋丸處理
為提高彈簧的疲勞強(qiáng)度需進(jìn)行拋丸處理。彈丸直徑0.3—0.5mm。采用壓縮空氣噴射時(shí),壓縮空氣壓力為0.4—0.5MPa;用離心機(jī)拋丸,彈丸的線速度為70m/s。經(jīng)拋丸處理的彈簧使用壽命能提高一倍以上。
中譯英:
1 Spring material and technical requirements
Spring materials for 50CrVA steel, the hardness of HRC45-49technical requirements; in terms of the load within the compression spring length changes shall conform to the requirements. Helical compression spring processing technological process is: spring roll, recrystallization annealing, quenching, tempering, correction and cutting, polishing, grinding end face, correction, low temperature stress, the finished product.
2 Helical compression spring heat treatment process
(1) the recrystallization annealing
Spring roll forming, must undertake the recrystallization annealing treatment, so that the spring stable geometric size, reducing the quenching deformation of. Recrystallization annealing temperature is 550℃-650 ℃, holding1- 1.5h air cooling. A small amount in the salt bath furnace in large quantities, using continuous resistance furnace with controlled atmosphere.
(2) quenching
In the salt bath furnace quenching, springs should be tied with wire evenly, or the spring is sheathed on the mandrel heating. When heated to ensure the surface oxidation and decarbonization of spring five. Salt bath should be carefully dna. Can also be in the controllable atmosphere box-type furnace heating, the heating temperature is 850±10 ℃, holding 10-15min, furnace oil quenching through.
(3) tempering
Quenching and tempering can be two times. The first correction correction of tempering, tempering temperature should generally be lower final tempering temperature20 ℃, holding 10-15min, released air cooling. Then the final tempering, in spring dimensions after correction, the spring is arranged in the tempering stereotypes fixture on final tempering. Tempering stereotypes fixture should ensure that the spring pitch and free length to meet the requirements. Tempering temperature 420±10 ℃, holding 30-35min, out of water.
(4) shot blasting
In order to improve spring fatigue strength for shot blasting. The projectile diameter 0.3-0.5mm. Using jets of compressed air, compressed air pressure of 0.4-0.5MPa; centrifuge projectile blasting, the line speed is 70m/s. By shot blasting treatment of the service life of the spring can improve more than doubled.
(圖/文http://www.one-bg.com/)
|