在使用三輥研磨機的時候,往往會出現這樣或那樣的問題,機器本身也會有一些問題出現,所以在使用的時候我們往往有很多地方需要注意,下面就來簡單的說一下需要注意的地方。
當遇到流開型而且是向著開方向流時,這樣的情況下汽蝕、沖蝕就會主要作用在密封面上,使閥芯根部和閥芯閥座密封面很快就遭受破壞,這時流閉型就會向著閉方向流,然而汽蝕、沖蝕作用使得節流之后的閥座密封面以下會受到保護密封面和閥芯根部,從而能夠延長壽命。作為流開型使用的閥門,當能夠進行延長壽命的問題較為突出時,那么只需要改變流向就可以延長它的壽命。
如果需要增長節流通道,那么簡單的方法就是加厚閥座,使閥座孔增長,這樣就形成更長的節流通道。這樣小小的改進卻又很大的用處,一方面可以使流閉型節流后的突然擴大,能夠將機器中容易出現問題的部位轉移破壞位置,使之遠離密封面的作用;而且從另一方面來說,又增加了節流阻力,減小了壓力的恢復程度,使汽蝕減弱。有的把閥座孔內設計成臺階式、波浪式,就是為了增加阻力,削弱汽蝕。這種方法在引進裝置中的高壓閥上和將老的閥加以改進時經常使用,也十分有效。
有些時候為了抗汽蝕(破壞形狀如蜂窩狀小點)和抗沖刷(流線型的小溝),則需要進行改用耐汽蝕和沖刷的特殊材料來制造節流件。這種特殊材料有司太鋼、硬質合金等,如果是為了抗腐蝕,可改用更耐腐蝕,并有一定機械性能、物理性能的材料。這種材料分為非金屬材料和金屬材料兩類。
三輥研磨機的使用注意事項還有很多,以上所例舉的不過是其中的幾項而已,如果想要進一步了解其它的注意事項快實際的辦法就是親自進行操作,在實踐中總結經驗,為自己的使用打下良好的基礎。
中譯英:
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 location, 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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