Three-stage pressure reduction equal-percent characteristic adjustment control valve for boiler system

Abstract

The invention discloses a three-stage pressure reduction equal-percent characteristic adjustment control valve for a boiler system. The three-stage pressure reduction equal-percent characteristic adjustment control valve for the boiler system comprises a valve body (1), a valve rod (6), a valve cover (8) and a combined valve sleeve (2); the combined valve sleeve comprises an inner-layer equal-percent adjustment valve sleeve (3), a middle pressure reduction valve sleeve (4) and an outer-layer pressure reduction valve sleeve (5) in pressure welding in sequence; a valve element (7) is matched inthe inner-layer equal-percent adjustment valve sleeve; and the inner-layer equal-percent adjustment valve sleeve, the middle pressure reduction valve sleeve and the outer-layer pressure reduction valve sleeve are provided with through holes uniformly distributed on the surfaces and staggered in the axial directions, wherein the areas of the through holes in the inner-layer equal-percent adjustmentvalve sleeve are linearly increased gradually in the axial direction of the combined valve sleeve from bottom to top. The three-stage pressure reduction equal-percent characteristic adjustment control valve for the boiler system has the beneficial effects of full utilization of superheated steam energy to save the energy and achievement of multiple purposes to reduce the power plant boiler construction cost.

Description

technical field [0001] The invention relates to a regulating valve, in particular to a regulating valve with flow rate equal percentage characteristics. Background technique [0002] Regulating valves are used to adjust process parameters such as medium flow, pressure, temperature, and liquid level in the field of industrial automation process control. According to the control signal in the automation system, the opening of the valve is automatically adjusted, so as to realize the adjustment of medium flow, pressure, temperature and liquid level. The regulating valve is usually composed of two parts: an electric actuator or a pneumatic actuator and a valve body. There are mainly two types of straight-through single-seat type and straight-through double-seat type. The latter has the characteristics of large flow capacity, small unbalance and stable operation, so it is usually especially suitable for occasions with large flow, high pressure drop and less leakage. The angular...

AI Technical Summary

Problems solved by technology

However, the labyrinth path of the labyrinth valve sleeve is easily blocked by impurities in the medium, thereby destroying the performance of the regulating valve, making it unable to adjust or meet the maximum flow requirement. At the same time, the production process of the labyrinth valve sleeve is difficult and time-consuming. The labyrinth orifice plate needs to be engraved and milled by the CNC machining center, which has high requirements on the operator and takes a lot of time, which prolongs the production cycle and increases the manufacturing cost; at the same time, it is equipped with a regulating valve and a pressure reducing valve to increase the construction cost of the boiler system; The medium regulating valve only adjusts the flow rate but cannot control the pressure behind the valve, and the blocked flow causes waste of steam energy; the high-pressure steam of the ordinary plunger-type valve sleeve regulating control valve concentrates through the throttling place, and the flash cavitation has a great impact on the opening and closing parts. Damage the opening and closing parts to destroy the valve sealing surface

For example, the Chinese Utility Model Patent Application No. CN201120011607.1 discloses a labyrinth control valve, the valve seat (2) is fixed with a valve sleeve assembly (5), and the valve sleeve assembly (5) is composed of a plurality of valve sleeve monomers (6 ) are stacked together, and there are multiple labyrinth-like curved media channels (7) radially between the inner wall and the outer wall of each valve sleeve unit (6), which are difficult to process and high in manufacturing cost, and the labyrinth path is easily Impurities in the medium are clogged

Another example is the Chinese invention patent application number CN201310133914.0 which discloses a high pressure differential regulating valve sleeve, which includes at least one multi-layer lamination unit, and the multi-layer lamination unit includes sequentially stacked annular base plates (1) and at least two annular descending plates. The pressure plate I (2) and the annular pressure-reducing plate II (3), the annular pressure-reducing plate I (2) has a rectangular through-hole (4), and the annular pressure-reducing plate II (3) has a U-shaped through-hole ( 5), two annular pressure-reducing plates (2) and (3) are arranged alternately, and the rectangular through-hole (4) and the U-shaped through-hole (5) communicate with each other, but it cannot control the pressure behind the valve, resulting in waste of steam energy

Images