超高壓針閥一般采用角形單座結(jié)構(gòu),加工簡(jiǎn)單,閥座容易配換,閥芯為單導(dǎo)向結(jié)構(gòu)。閥門角形單座結(jié)構(gòu)流路簡(jiǎn)單,阻力小,適用于高壓差、高粘度、含懸浮物和顆粒狀物質(zhì)流體,可以避免結(jié)焦和堵塞,也便于自凈和清洗。閥芯和閥座是超高壓針閥進(jìn)行開關(guān)控制的兩個(gè)核心零件,組成超高壓針閥開關(guān)的動(dòng)密封副。通過控制閥芯與閥座之間錐形密封面的接觸與分離,實(shí)現(xiàn)閥通道的關(guān)閉和開啟。閥芯與密封圈之間的圓周密封面構(gòu)成閥的滑動(dòng)密封副,用于保證閥室與外界的密封。

Ultra high pressure needle valves generally adopt an angular single seat structure, which is easy to process, the valve seat is easy to replace, and the valve core is a single guide structure. The valve angle single seat structure has a simple flow path, low resistance, and is suitable for fluids with high pressure difference, high viscosity, suspended and granular substances. It can avoid coking and blockage, and is also convenient for self-cleaning and cleaning. The valve core and valve seat are the two core components of the ultra-high pressure needle valve for switch control, forming the dynamic sealing pair of the ultra-high pressure needle valve switch. By controlling the contact and separation of the conical sealing surface between the valve core and valve seat, the valve channel can be closed and opened. The circumferential sealing surface between the valve core and the sealing ring forms the sliding sealing pair of the valve, which is used to ensure the sealing between the valve chamber and the outside world.

閥芯采用針形,靠錐面密封,一般閥芯錐角為59°,閥座錐角為60°。實(shí)驗(yàn)證明在開錐孔時(shí),錐角選取45°～60°時(shí),孔邊緣的應(yīng)力集中系數(shù)小,且使應(yīng)力出現(xiàn)在錐孔的小端。閥座錐角大,閥芯錐角小時(shí),靠上表面密封,有利于提高閥的使用壽命

The valve core adopts a needle shape and is sealed by a conical surface. Generally, the valve core cone angle is 59 °, and the valve seat cone angle is 60 °. Experimental results have shown that when opening a conical hole, when the cone angle is selected from 45 ° to 60 °, the stress concentration coefficient at the edge of the hole is small, and the stress appears at the small end of the conical hole. The valve seat cone angle is large, while the valve core cone angle is small. Sealing on the upper surface is beneficial for improving the service life of the valve

在出現(xiàn)高壓調(diào)閥抖動(dòng)的情況時(shí)，我們可以首先查看閥門指令是否發(fā)生數(shù)據(jù)上的變化，來進(jìn)行分別的處理。

When there is a shaking of the high-pressure regulating valve, we can first check whether there is a change in the valve instruction data to process it separately.

一、閥門指令未發(fā)生變化，那么問題就可能出現(xiàn)在伺服卡以及伺服閥之上。若是閥門指令未發(fā)生變化并且伺服卡輸出穩(wěn)定，則問題可能是伺服閥卡澀或者油動(dòng)機(jī)與閥門連接有卡澀。若是此時(shí)伺服卡輸出晃動(dòng)，則可能的問題有：伺服卡PI參數(shù)不合理、閥位反饋波動(dòng)（LVDT故障、LVDT屏蔽不良等問題引起）、伺服卡故障。

1、 If the valve command has not changed, then the problem may occur on the servo card and servo valve. If the valve command has not changed and the servo card output is stable, the problem may be that the servo valve is stuck or the connection between the hydraulic motor and the valve is stuck. If the output of the servo card shakes at this time, possible problems include: unreasonable PI parameters of the servo card, valve position feedback fluctuations (caused by LVDT faults, poor LVDT shielding, etc.), and servo card faults.

二、閥門指令自身發(fā)生變化，則我們需要查詢?yōu)槭裁磿?huì)出現(xiàn)指令的抖動(dòng)。若是在并網(wǎng)之前就發(fā)生指令波動(dòng)的問題，則原因可能有：轉(zhuǎn)速PI參數(shù)不合理，引起過調(diào)；轉(zhuǎn)速通道故障，引起轉(zhuǎn)速信號(hào)的非正常波動(dòng)，進(jìn)而導(dǎo)致轉(zhuǎn)速回路的輸出波動(dòng)。而轉(zhuǎn)速通道故障的可能原因有：磁阻探頭故障、轉(zhuǎn)速屏蔽不良等。而若是在并網(wǎng)之后發(fā)生閥位指令波動(dòng)，則原因可能有：功率、壓力回路PI參數(shù)不合理，導(dǎo)致出現(xiàn)過調(diào)；閥門運(yùn)行在流量曲線拐點(diǎn)處；一次調(diào)頻轉(zhuǎn)速波動(dòng)；遙控指令波動(dòng)等。

2、 If the valve instruction itself changes, we need to investigate why there is instruction jitter. If there is a problem of command fluctuation before grid connection, the reason may be: unreasonable speed PI parameters, causing overshoot; The malfunction of the speed channel causes abnormal fluctuations in the speed signal, which in turn leads to fluctuations in the output of the speed circuit. The possible causes of speed channel failure include: magnetic resistance probe failure, poor speed shielding, etc. If valve position command fluctuations occur after grid connection, the reasons may include: unreasonable PI parameters of power and pressure circuits, leading to overshoot; The valve operates at the inflection point of the flow curve; Fluctuation of primary frequency modulation speed; Remote control command fluctuations, etc.