气弹簧

机械密封弹簧压缩量测量直接用卡尺测是，先测量在自由状态下的弹簧伸缩量，再测量机封安装到位后的量，一减是压缩量。
集装式密封可以不用自己去定压缩量，因为整个密封装好时已定好了，非集装式密封要根据不同的泵的类型来测量。
单弹簧机械密封的压缩量为50%—70%，大概密封压死后放开3—5mm，多弹簧(碟形簧)的压缩量为90%左右，即机械密封压死后放开1.5—2.5mm即可。同时还要考虑密封面的宽窄，弹簧的力度，工作时受力状态。
调节弹簧压缩量是为了满足弹簧比压，而不是为压缩量而压缩量，不管它是单弹簧还是多弹簧。通常，机泵机械密封的弹簧比压大致控制在1.3—2.8kgf/cm2左右。佳取值多少要根据实际工况条件、摩擦副配对材质、补偿环辅助密封圈结构型式和要与载货系数K值相适应等等。
泵用机械密封检修中的误区：
(1)弹簧压缩量越大密封效果越好。其实不然，弹簧压缩量过大，可导致摩擦副急剧磨损，瞬间烧损；过度的压缩使弹簧失去调节动环端面的能力，导致密封失效。
(2)动环密封图越紧越好。其实动环密封圈过紧有害无益。一是加剧密封圈与轴套间的磨损，过早泄漏；二是增大了动环轴向调整、移动的阻力，在工况变化频繁时无法适时进行调整；三是弹簧过度疲劳易损坏；四是使动环密封圈变形，影响密封效果。

中译英：
Mechanical seal spring compression measurement directly with the caliper measurement is measured in free state, before the spring expansion, and then measuring machine seal mounted in place after the volume, decrease is the amount of compression.
Assembled seal can not own to set compression, because the entire seal installed has been made, a cartridge seal according to the different type of pump to measure.
Single spring mechanical seal compression amount is 50%-70%, probably after the opening sealing crushed 3-5mm, multi spring(spring dish)the amount of compression of about 90%, i.e. mechanical seal killed after the release of 1.5-2.5mm. While also considering the seal face width, the spring strength, work stress state.
Regulating the amount of compression springs to meet the spring pressure, but not for the amount of compression and compression amount, whether it is a single spring or spring. Usually, the pump mechanical seal spring pressure generally control in 1.3, about 2.8kgf/cm2. Best value number according to the actual working condition, friction pairs materials, compensation ring auxiliary seal ring structure and with the cargo coefficient K value is adapted and so on.
Pump mechanical seal repair error:
(1) the amount of spring compression of the seal effect is better. In fact, excessive compression spring, can lead to rapid wear of friction pairs, instantaneous burning; excessive compression spring failed to regulate the ability of actin ring face, causing the sealing failure.
(2) dynamic ring seal chart tightening the better. In fact, dynamic tight ring seals harmful. A sealing ring and the shaft sleeve is aggravate the wear, premature leakage; two is to increase the dynamic axial adjustment of the resistance movement, the frequent changes in working conditions can not be adjusted in good time; three spring fatigue is easy to damage; the four is to make dynamic ring seal deformation, the impact of sealing effect.
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