在使用三辊研磨机的时候,往往会出现这样或那样的问题,机器本身也会有一些问题出现,所以在使用的时候我们往往有很多地方需要注意,下面就来简单的说一下需要注意的地方。
当遇到流开型而且是向着开方向流时,这样的情况下汽蚀、冲蚀就会主要作用在密封面上,使阀芯根部和阀芯阀座密封面很快就遭受破坏,这时流闭型就会向着闭方向流,然而汽蚀、冲蚀作用使得节流之后的阀座密封面以下会受到保护密封面和阀芯根部,从而能够延长寿命。作为流开型使用的阀门,当能够进行延长寿命的问题较为突出时,那么只需要改变流向就可以延长它的寿命。
如果需要增长节流通道,那么简单的方法就是加厚阀座,使阀座孔增长,这样就形成更长的节流通道。这样小小的改进却又很大的用处,一方面可以使流闭型节流后的突然扩大,能够将机器中容易出现问题的部位转移破坏位置,使之远离密封面的作用;而且从另一方面来说,又增加了节流阻力,减小了压力的恢复程度,使汽蚀减弱。有的把阀座孔内设计成台阶式、波浪式,就是为了增加阻力,削弱汽蚀。这种方法在引进装置中的高压阀上和将老的阀加以改进时经常使用,也十分有效。
有些时候为了抗汽蚀(破坏形状如蜂窝状小点)和抗冲刷(流线型的小沟),则需要进行改用耐汽蚀和冲刷的特殊材料来制造节流件。这种特殊材料有司太钢、硬质合金等,如果是为了抗腐蚀,可改用更耐腐蚀,并有一定机械性能、物理性能的材料。这种材料分为非金属材料和金属材料两类。
三辊研磨机的使用注意事项还有很多,以上所例举的不过是其中的几项而已,如果想要进一步了解其它的注意事项快实际的办法就是亲自进行操作,在实践中总结经验,为自己的使用打下良好的基础。
中译英:
In the use of three roller grinding machine when, often can appear such or in that way, the machine itself also has some problems, so when in use, we tend to have so many places that need attention, here is simple talk about places that need attention.
When the flow type and is open toward the opening direction of flow, cavitation, erosion of such cases will be a major role in the sealing surface, so that the roots spool and spool valve seat sealing surface soon destroyed, then the flow closed will toward the close direction flow cavitation, erosion, however the throttle after the seat sealing face the following protected seal surface and a spool root, so as to prolong the life of. As the flow opening type using the valve, when can the issue of prolonging life is more prominent, so only need to change the flow can prolong its life.
If you need to increase the throttle channel, so the simplest way is to thicken the seat, so that the valve seat hole growth, thus forming a longer throttle channel. Such a small improvement is very useful, on one hand can make the flow of closed type throttle after the sudden expansion, can machine the problems in site of metastatic failure locations, away from the sealing surface of the role; and on the other hand, increase of cutting resistance, reducing pressure recovery, so that reduced cavitation. Some of the valve seat hole is designed into a stepped, wavy, is to increase the resistance, weaken cavitation. This method introduced in the device in the high pressure valve and the old valve to be improved when used regularly, but also very effective.
Sometimes in order to cavitation(failure shapes such as honeycomb dots)and erosion(streamlined groove), you will need to be converted to resistance to cavitation and erosion of the special material to manufacture a throttling element. This special material department Taigang, the hard alloy and so on, if it is to resist corrosion, can use more resistant to corrosion, and some mechanical properties, physical properties of materials. This material is divided into non-metallic materials and metal materials two.
Three roller grinding machine using notes there are many, the above example is but one of several only, if you want to further the understanding of other matters to the attention of the fastest and most practical approach is to operate, in practice summary experience, for its own use to lay a good foundation.
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