CN2107579U - Multi-operating mode regulating valve - Google Patents

Abstract

The utility model relates to a multi-operating condition regulating valve which is composed of a valve body, a valve base, a plunger valve core and a sleeve barrel thereof. Three layers of flow guiding (throttling) holes are arranged from bottom to top along the traveling path of a valve flap on the wall of the sleeve barrel in sequence; the lowest layer is a valve cage structure of third-stage cavitation erosion prevention, the middle layer is provided with hyperbola-shaped flow guiding holes used for satisfying the designing flow quantity of the working operating state of the regulating valve, and the highest layer is provided with the large-caliber rectangular flow guiding holes used for satisfying the maximum designing flow quantity of the regulating valve. The valve is suitable for the three operating conditions of the switching, the operation and the accident of equipment. The utility model also avoids the cavitation erosion and the blowing damage of valve body components caused by high pressure liquid and also reduces energy consumption.

Description

Multi-operating mode regulating valve

The utility model belongs to a kind of modulating valve.

The large and medium-sized boiler feed water modulating valve of industries such as electric power, chemical industry, oil, for satisfying the requirement of equipment safe operation in shutdown process, primary problem is to avoid high-pressure liquid directly blowing damage and causing being not closed completely the drawback that leakage phenomenon is serious valve seat, flap sealing surface as far as possible.For example, power station 410T/H high pressure-temperature boiler, when valve was opened in off position or just, its leakage rate tended to up to 200T/H.Current comparatively advanced technological scheme is: the whole strokes along the spool plunger action of modulating valve, and adopt three grades of nozzle shapes to prevent the cavitation throttle structure, be called big pressure-difference valve, valve cage structure as shown in Figure 4, abroad the product of FISHER company promptly belongs to this type of.The narrow limitation of this valve is that the big pressure reduction that it is only applicable under the equipment start-stop operating mode regulates, and its deficiency is, when normal operation or accident condition, because of the system flow resistance causes the energy consumption increase greatly.

The purpose of this utility model is the use narrow limitation that overcomes above-mentioned valve, proposes a kind ofly to be suitable for unit start and stop, the normal modulating valve under operation and three kinds of operating modes of accident simultaneously, reduces the regulating valve system internal resistance of flowing, the effect of saving operation energy consumption thereby reach.

The purpose of this utility model realizes by following structural type, promptly on modulating valve plungers valve core sleeve wall, in the flap stroke range, from last and on have three layers of pod apertures successively; The basecoat pod apertures is three grades of nozzle shape valve cage structures, to adapt to the High Pressure Difference operating mode of modulating valve when opening-closing process just begins; Middle one deck pod apertures is the hyperbola pod apertures, passes through smoothly with the liquid stream that satisfies under the normal operating conditions of equipment; Last layer then is the rectangle discharge orifice of its conductance greater than preceding two-layer pod apertures conductance, to satisfy the needs of modulating valve design maximum flow under the accident conditions.Structural type by above three layers of pod apertures combination is to constitute essential features of the present utility model.

In order to guarantee that this kind valve can control to certain leakage standard, the sealing of dynamic and static gaps between the flap of this modulating valve and the valve pocket can be adopted multiple tracks profiled seal coil structures, and fixedly piezometer ring wherein also can make seal ring, makes it have double action.

In addition, between plunger valve rod and valve gap, also be added with stuffing box packing, on the gland at an upper portion thereof, be provided with special hole, can inject special high-temperature seal adhesive, with prevent because of filler damage cause leak outside out of service.

All adopt between the valve seat of this modulating valve, valve gap and the valve body and the cap thread binding, so that change easily damaged parts.

Advantage of the present utility model mainly is: because of the combination of three kinds of structural types of pod apertures in the valve rod plunger cavity, make this modulating valve adapt to equipment start-stop, operation and three kinds of operating modes of accident, prevent high pressure liquid stream blowing of valve body parts decreased with cavitation in, can also in running, reduce energy consumption, and guarantee to let out under the accident condition sufficient valve design maximum flow again, in addition, appropriate mode of execution of the present utility model, can also control leakage effectively, guarantee the normal operation of equipment; And maintenance is convenient to change easily damaged parts easily, and the valve body life-span is prolonged.

Specific embodiment of the utility model as shown in drawings.The modulating valve front section view that is a design maximum flow and is 500T/H shown in Figure 1.This valve is equipped with valve seat (3) on valve body (1) internal valve seat cushion (2), be located in the plungers valve core sleeve on the valve seat (3), divide three zones along flap (7) stroke, near one section zone of liquid outflow opening end is to be surrounded by overcoat (5), middle cover (6) and interior cover (8), three grades of anti-cavitation valve cages of nozzle shape as shown in Figure 2; Middle one section zone has the hyperbola pod apertures (A) that is suitable for operating conditions; Topmost one section zone has the rectangle pod apertures (B) that is suitable for letting out under the accident conditions sufficient design maximum flow.

In the equipment start-stop operating mode, liquid stream is regulated by three grades of valve cages, even pressure reduction reaches more than the 30MPa before and after this modulating valve, this valve can also be regulated arbitrarily between 0～150T/H flow.When nominal situation, wish that the internal resistance of modulating valve itself should be as far as possible little, for example, when pressure reduction was 0.3-0.5MPa, flow can satisfy the requirement of 450T～500T/H.In accident conditions, though pressure reduction has only 0.1MPa before and after the modulating valve, can satisfy the requirement of letting out sufficient design maximum flow.

Present embodiment employing multiple tracks special-shaped seal ring structural type as shown in Figure 3 realizes the sealing of dynamic and static gaps between flap and the valve pocket, it is by the multiple cooperation of the packing ring (9) among Fig. 1, (10) selfsealings circle (11) and equal trim ring (12) and seal ring (19), meets guaranteeing Level leakage standard.

Present embodiment influences equipment and normally moves in order to prevent because of the damage of the stuffing box packing (16) between plunger valve rod (20) and the valve gap (14) and to leak outside, and is added with gland (17) in valve gap (14) top.The special hole (21) that can inject the high temperature sealing is housed on gland (17).

Adopt respectively between the valve body of present embodiment (1) and valve seat (3) or the valve gap (14) and cap nut (4) and (13) binding cooperate, therefore easily damaged parts can use cemented carbide modified, life-span can reach about 60,000 hours, and change easily, so that valve body (1) design service life that is fixedly mounted on the support (18) is higher, can reach more than 250,000 hours.

In addition, and cap nut (13) on, also be added with water-proof mat (15), further strengthen the sealed against leakage ability.

Claims (4)

1, a kind of multi-operating mode modulating valve is made up of valve body, valve seat, plungers valve core and sleeve thereof, it is characterized in that, on the plungers valve core sleeve wall of described modulating valve, along the flap travel paths, has three layers of pod apertures from bottom to top successively; The basecoat pod apertures is three grades of nozzle shape valve cage structures; Middle one deck pod apertures is the hyperbola pod apertures; Last layer then is the rectangle pod apertures of its conductance greater than preceding two-layer pod apertures conductance.

2, multi-operating mode modulating valve according to claim 1 is characterized in that: the multiple tracks fixing ring structure that the sealing configuration of dynamic and static gaps is made up of packing ring (9,10), the equal trim ring (12) of selfsealings circle (11) and seal ring (19) between flap and the valve pocket.

3, multi-operating mode modulating valve according to claim 1 is characterized in that: be added with stuffing box packing (16) between plunger valve rod (20) and the valve gap (14), gland (17) is provided with special hole (21) at an upper portion thereof, annotate with high-temperature seal adhesive in hole (21).

4, multi-operating mode modulating valve according to claim 1 is characterized in that: between valve seat (3) or the same valve body of valve gap (14) (1) respectively with and cap nut (4) and (13) link cooperation.

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