CN103307295B - Low friction flat gate valve - Google Patents

Abstract

The present invention relates to a kind of low friction flat gate valve, comprise valve body, valve gap, valve seat, flashboard, valve rod and handwheel, in valve body, co-axial seal is fixed with a valve seat, and in this valve seat, longitudinal sliding motion guiding is provided with a flashboard; This flashboard upper end is longitudinally coaxially fixed with valve rod, valve gap is stretched out on this valve rod top and valve rod top above valve gap is coaxially installed with a handwheel, inside valve gap between described valve rod and valve gap, combined packing is installed, with the valve seat of the axial contact position of valve body on be provided with spring eye and be top-loaded with a spring in this spring eye; With the valve seat surface of rams contact on be provided with a wedge shape boss, be shaped with guiding surface rank with on the flashboard of this wedge shape boss corresponding position.This plate valve significantly reduces the wearing and tearing of sealing surface of seat and the unlatching moment of valve, substantially increases the working life of valve.

Description

Low friction plate gate valve

technical field

The invention belongs to the field of valves, in particular to a low-friction flat gate valve.

Background technique

At present, during the opening and closing process of most flat gate valves, the sealing surface of the valve seat and the gate is always in contact, that is, every time the valve is opened and closed, the sealing surfaces of the valve seat and the gate are constantly rubbing against each other. The switching torque of the valve is large, and the wear of the valve seat and the gate plate is accelerated, resulting in a short service life of the valve.

Contents of the invention

The object of the present invention is to overcome the disadvantages of the prior art and provide a low-friction slab gate valve with small torque, easy operation and long service life.

The present invention solves its technical problem and realizes by taking the following technical solutions:

A low-friction slab gate valve, including a valve body, a valve cover, a valve seat, a gate plate, a valve stem and a hand wheel. A pair of valve seats are coaxially sealed and fixed in the middle of the flow channel, and a gate plate is installed in a longitudinal sliding guide between the two valve seats; A hand wheel is coaxially installed on the upper part of the valve stem above the valve cover, and a combined packing is installed on the inner side of the valve cover between the valve stem and the valve cover, and the feature is that: there is a valve seat on the axial contact position with the valve body The spring hole is topped with a spring in the spring hole; a wedge-shaped boss is arranged on the valve seat surface in contact with the gate plate, and a guide slope is formed on the gate plate corresponding to the wedge-shaped boss.

Moreover, a plurality of sealing rings are installed at intervals between the radial contact surfaces of the valve seat and the valve body.

Moreover, a protective cover is fixedly installed on the valve stem at the upper end of the hand wheel, and an indicating rod is fixedly installed on the protective cover.

Advantage and positive effect of the present invention are:

1. When the flat gate valve is closed, even if the pressure is very low, the valve seat can float toward the gate plate through the pre-tightening force of the spring and contact with the gate plate, so as to achieve a good sealing effect.

2. When the flat gate valve is opened, the valve seat is quickly disengaged from the gate through the relative sliding between the wedge-shaped boss of the valve seat and the guide slope of the gate step, and the compression of the spring by the valve seat, thereby effectively reducing the The wear of the sealing surface of the valve seat and the opening torque of the valve are reduced, and the service life of the valve is greatly improved.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Figure 2 is an enlarged view of the local structure of part A in Figure 1;

Figure 3 is a schematic diagram of the partial structure of part A when the valve is in an open state.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and through specific embodiments. The following embodiments are only descriptive, not restrictive, and cannot limit the protection scope of the present invention.

A low-friction flat gate valve, comprising a valve body 8, a valve cover 4, a valve seat 7, a gate plate 6, a valve stem 5, a handwheel 2 and a protective cover 1, as shown in Figure 1, the longitudinal upper end of the valve body is coaxially fixed Equipped with a bonnet, the valve body is coaxially formed with a flow channel in the transverse direction, and a pair of valve seats are coaxially sealed in the middle of the flow channel in the valve body, and a gate for controlling the opening and closing of the flow channel is installed between the two valve seats for longitudinal sliding guidance. The upper end of the gate plate is coaxially fixed with a valve stem, the upper part of the valve stem protrudes from the bonnet and a handwheel is coaxially installed on the upper part of the valve stem above the bonnet, and a valve stem is fixed on the upper end of the handwheel. Protective cover. An indicator rod (not marked in the figure) is fixed on the protective cover for easy observation during operation. When in use, the valve stem is driven up and down by rotating the hand wheel to drive the gate plate to move up and down to control the gate valve. open and close.

In order to ensure the tightness of the valve stem, a combined packing 3 is installed on the inner side of the valve cover between the valve stem and the valve cover.

The innovation point of the present invention is:

A spring hole is provided on the valve seat at the axial contact position with the valve body, and a spring 11 is installed in the spring hole. A wedge-shaped boss 9 is arranged on the valve seat surface where the plate contacts, and a guide slope step is formed on the gate corresponding to the wedge-shaped boss, and the thickness of the gate plate below the guide slope step is greater than that above the guide slope step. When the valve is closed, the gate moves down, and the guide slope slides over the wedge-shaped boss of the valve seat, and the valve seat quickly floats toward the gate under the pre-tightening force of the spring, and fits with the gate to achieve a good sealing effect; During the opening process of the valve, the gate plate moves, and the guide slope of the gate plate slides relative to the wedge-shaped boss of the valve seat, and the valve seat is disengaged from the gate plate. The position contact effectively reduces the friction between the gate and the valve seat, thereby reducing the wear of the sealing surface of the valve seat, reducing the opening torque of the gate, and improving the service life of the valve.

In order to ensure the tightness between the valve seat and the valve body, a plurality of sealing rings 10 are installed at intervals on the radial contact surfaces of the valve seat and the valve body.

Claims (2)

1. a low friction flat gate valve, comprise valve body, valve gap, valve seat, flashboard, valve rod and handwheel, the longitudinal upper end of valve body is coaxially fixed with valve gap, in valve body, transverse uniaxial is shaped with runner, in the middle part of runner in valve body, co-axial seal is fixed with a pair valve seat, and between two valve seats, longitudinal sliding motion guiding is provided with a flashboard; This flashboard upper end is longitudinally coaxially fixed with valve rod, valve gap is stretched out on this valve rod top and valve rod top above valve gap is coaxially installed with a handwheel, inside valve gap between described valve rod and valve gap, combined packing is installed, it is characterized in that: with the valve seat of the axial contact position of valve body on be provided with spring eye and be top-loaded with a spring in this spring eye; With the valve seat surface of rams contact on be provided with a wedge shape boss, be shaped with guiding surface rank with on the flashboard of this wedge shape boss corresponding position, the flashboard thickness below these guiding surface rank is greater than above guiding surface rank; The radial surface of contact interval of described valve seat and valve body is provided with multiple seal ring.

2. low friction flat gate valve according to claim 1, is characterized in that: the valve rod of described handwheel upper end is fixed with a safety cover, this safety cover is fixed with an indicating arm.