Manual lapping device for shut-off valves

Abstract

The invention discloses a manual grinding device used for a check valve. The manual grinding device comprises a grinding unit and a manual driving unit, wherein the manual driving unit is connected with the grinding unit through a transmission rod. The manual grinding device further comprises a positioning unit located between the manual driving unit and the grinding unit. The positioning unit comprises a fixing disc arranged on the transmission rod in a sleeving manner. Bolt holes are formed in the fixing disc. The fixing disc is used for being placed at the position of a flange of an upper valve opening in the valve and is fixedly connected with the flange through bolts. The part, located above the grinding unit, of the transmission rod is sleeved and connected with a main bearing. The distance between the main bearing and the grinding unit is smaller than 2 mm. A plurality of axially-extending positioning rods are evenly arranged on the outer ring of the main bearing. The positioning rods extend towards the fixing disc and penetrate the fixing disc. The inner ring of the main bearing is fixedly connected with the grinding unit. By means of the manual grinding device, the grinding unit can be better prevented from deviating and inclining, and therefore it can be ensured that the grinding unit can achieve a uniform grinding effect on a sealing face of the check valve.

Description

technical field [0001] The invention relates to the field of valves, in particular to a grinding device for the sealing surface of a cut-off valve. Background technique [0002] After a period of use, the flatness of the sealing surface of the valve will decrease, requiring maintenance. For ordinary structure valves with relatively small diameters (such as diameters less than 100mm), electric grinders are usually used to regularly grind and repair the sealing surface, so as to eliminate internal leakage caused by defects formed during operation. However, for cut-off valves with large diameters and complex structures, such as PL135 / 50-WY963Y-P5515V high-pressure bypass conversion valves, electric grinders cannot be used for grinding. The reason is that the structure of this valve is complex, the diameter is large (usually about 200mm), and the grinding accuracy of the sealing surface is extremely high. If improper grinding causes eccentric wear, it is easy to cause the valv...

AI Technical Summary

Problems solved by technology

However, the above patent documents do not take into account the existing valves, mainly because the valve chamber of the globe valve body is in contact with the flowing medium for a long time during use, which will cause corrosion and rust, so it is no longer possible to guarantee the position of the upper valve port. Dimensional accuracy, the guide is fixed at the position of the upper valve port, and the positioning effect is not strong; and from the drawings of the above patent documents, it can be concluded that the grinding unit is only connected to the transmission rod, and between the first guide and the grinding unit There is still a very long end distance, which is used to make the transmission rod drive the grinding unit to contact the sealing surface of the valve. Due to the lack of positioning devices in this distance, and the length is long, the transmission rod is still prone to deviation, although it is possible It is a small amount, but for valves with high sealing requirements, the offset cannot be ignored

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