JPS60125481A - Control valve - Google Patents

Abstract

PURPOSE:To prevent a guide portion from being adhered by a fluid by providing a valve plug having a guide portion, the section of which is polygonal, and letting a flash liquid flow between a guide ring and a valve plug. CONSTITUTION:A valve stem 1 is driven by air pressure, so that valve plugs 2, 3 are moved up and down to open and close a valve. Generally, the section of the valve plug 3 contacting a guide ring 4 is preferably polygonal such as tetragonal, pentagonal, hexagonal, heptangular or octanogal, and the ridgeline of each vertical angle is slided in contact with the inner surface of the guide ring 4. A flash liquid introduced through a flash liquid nozzle 5 flows through a gap arc-shaped in section between the guide ring and the valve plug 3. Adhesion between the guide ring 4 and the valve plug 3 caused by slurry or polymerized fluid can be prevented by letting a flash liquid flow therebetween.

Description

[Detailed description of the invention] The present invention relates to preventing a remote control valve from sticking.

When handling slurry or polymerizable fluids in remote-controlled control valves using air pressure, electromagnetic force, etc., conventionally, the solid content of the slurry clogs the slit-like gap between the guide ring of the inner valve part and the cylindrical valve plug, or It often happens that the valve becomes inoperable due to accumulation of polymerizable liquid and clogging of the polymer, and the inventors of the valve have conducted intensive studies on this point each time, and as a result, they have arrived at the present invention. It was possible to solve the problem.

That is, the control valve according to the present invention is a remote control control valve in which the guide portion of the valve plug in the inner valve part has a polygonal cross-sectional shape such as a quadrangle, pentagon, hexagon, heptagon, or rectangular shape, and the guide ring and valve plug have a cross-sectional shape. The feature is that a flushing liquid is flowed in between to prevent the part from sticking due to slurry, polymerizable fluid, or the like.

The present invention will now be explained with reference to the drawings. In the angle valve shown in FIG. 1, the pulp stem 1 is driven by air pressure or the like, and the valve plug 2.3 is moved up and down to open and close the valve. The cross-sectional shape of the valve plug 3 in contact with the guide ring 4 is preferably about 4 to 8 squares, and as shown in FIG. (σ) The flush liquid introduced from the flush liquid nozzle 5 into the arcuate cross-sectional gap between the guide link 4 and the valve plug 30 is contaminated.The flag fluid used is one that does not cause problems even if mixed with the solvent of the handled fluid. do.

Next, an example will be explained.

Example: The resin liquid outlet control valve of the styrene resin polymerization pot is 2.1/2.
Angle valve B is used, and the guide portion of the conventional valve plug had a circular cross section, and the only gap between it and the guide ring was a slit-like clearance.

Therefore, we injected a flush liquid to avoid the risk of sticking due to polymers, but even so, the guide ring and valve plug still stuck due to polymers 4 to 5 times a year, and the control valve was overhauled each time. However, when the guide part of the valve plug of this control valve was modified to have a regular hexagonal cross section as shown in Figures 1 and 2 and flush liquid was injected, no sticking occurred even after one year. The cost savings in terms of maintenance were also significant.

[Brief explanation of the drawing]

1 and 2 show one example of a control valve according to the present invention, in which FIG. 1 is a longitudinal cross-sectional view, and FIG. 2 is a cross-sectional view taken along the line A-As in the first diagram. 100. Pulp stem 261. Valve plug head 300. Valve plug guide portion 401. Guide ring 510. Flush liquid inlet nozzle 600. Seat ring 703. Valve body 800. Cover 900. Patsukin 10.6. Gasket 11, York patent applicant Mitsui Toatsu Chemical Co., Ltd.

Claims (2)

[Claims] (1) In a remote control control valve, the cross-sectional shape of the guide part of the valve plug in the inner valve part is polygonal, and by flowing flush liquid between the guide link and the valve plug, the part is fixed by slurry or polymerizable fluid, etc. A control valve featuring prevention. (2) The method according to claim 1, wherein the cross-sectional shape is a regular hexagon.