GS-C251.0619,WCB.WCC,LCB,LCC,LC3,4C,4D,WC6,C5,C12, C12A,CA15，CF3,CF8(-196’C),CF3M,CF8M,CF8C,CD4MCu,CK3MC uN,ZG200-400,ZG230-450,ZG270-500,2G40Cr1,ZG20CrM0.2G15C r1Mo1V,ZG35Cr1MO.ZG16CrMOG(1Cr5Mo),ZG1Cr13,ZGOCr18Ni9 Ti.5A.KmTB Cr26.4A
Resin sand casting, etc.
Gate valve is a gate with opening and closing parts. The movement direction of gate is perpendicular to the direction of fluid. The gate valve can only be fully opened and closed. The parameters of unsuitable gate are different, usually 5 degrees. When the medium temperature is not high, it is 2 degrees 52'. Improve its technicality and make up for the deviation caused by the angle of sealing surface in the process of processing. This kind of gate is called elastic gate.
The opening and closing part of the gate valve is the gate. The movement direction of the gate is perpendicular to the direction of the fluid. The gate valve can only be fully opened and closed, and cannot be adjusted and throttled.
The gate has two sealing surfaces. The two sealing surfaces of the most commonly used mode gate valves form wedges. The wedge angle varies with the valve parameters, usually 5 degrees, and the medium temperature is 2 degrees 52'. Wedge gate valve can be made into a whole, called rigid gate; it can also be made into a gate that can produce slight deformation to improve its workability, make up for the deviation of sealing surface angle in the process of processing. This kind of gate is called elastic gate.
When the gate valve closes, the sealing surface can be sealed only by medium pressure, that is to say, the sealing surface of the gate can be pressed to the seat on the other side to ensure the sealing surface sealing, which is self-sealing. Most gate valves are forced to seal, that is, when the valve closes, the gate must be forced to the seat by external force to ensure the sealing surface.
The gate plate moves in a straight line with the stem, which is called the lift bar gate valve or the open bar gate valve. Usually there are trapezoidal threads on the lifting rod. Through the nut at the top of the valve and the guide groove on the valve body, the rotary motion is changed into linear motion, that is to say, the operating torque is changed into the operating thrust. When opening the valve, when the gate lifting height is equal to 1:1 times the valve diameter, the flow passage is completely open, but when running, this position cannot be monitored. In practical use, the vertex of the valve stem is used as the sign, that is, the position of the valve stem that is not moving is used as its full open position. In order to consider the lock phenomenon because of of temperature change, the stem usually is opened to the vertex position, and then back to 1/2-1 circle, as the position of the full open valve. Therefore, the full open position of the valve is determined by the position of the gate, that is, the stroke. Some gate valves, stem nuts set on the gate plate, hand wheel rotation to drive the rotation of the stem, and make the gate lift, this valve is called rotary bar gate valve, or dark bar gate valve.