Gate valve
Gate valve is used as a cut-off medium, the entire flow through the full open, the pressure loss of the media at this time is the smallest. Gate valves are generally applicable to the condition that does not require frequent opening and closing, and to keep the gate fully open or fully closed. Not suitable for use as a regulator or throttle. For high-speed flow of media, the gate in the local open conditions can cause the vibration of the gate, and vibration may damage the sealing surface of the gate and valve seat, and the throttle will suffer the media erosion. From the structural form, the main difference is the use of the form of the sealing element. According to the form of sealing elements, often divided into several different types of valve, such as: wedge gate valve, parallel gate valve, parallel gate valve, wedge gate, etc.. The most commonly used form is wedge type gate valve and parallel gate valve.
Globe valve
Valve stem and valve seat sealing surface. Open or close the valve stem is relatively short, and has a very reliable cutting action, making this valve is very suitable as a medium to cut off or adjust and use the throttle.
The cut-off valve of the valve once in the open position, and its valve seat and valve sealing surface between the no longer contact, and has a very reliable cutting action, and combine this valve is suitable for medium cut or regulation and throttle use.
The cut-off valve in the open position when, its seat and disc sealing surface between the is no longer in contact, so it's sealing surface mechanical wear small, as most of the cut-off valve seat and valve easily repaired or replaced seals without the need to remove the valve from the pipeline, which the valves and pipes welded into one of the occasions is very applicable. Media through the flow direction of such a change in the valve, the cut-off valve of the flow resistance is higher than other valves.
Common cut-off valve has the following: 1) angle type globe valve; in the angle type globe valve, the fluid needs to change only one direction, so that the pressure drop through the valve is smaller than the conventional structure of the cut-off valve. 2) DC type valve; in the DC type or Y-shaped valve, the valve body and the main channel flow into a slash, this flow state the extent of the damage than the conventional cut-off valve to small, so by the valve pressure loss is also the corresponding small. 3) plunger type valve: this form of cut-off valve is a variant of the conventional cut-off valve. In the valve, the valve and the valve seat is generally based on the principle of the plunger design. The valve flap is polished to be connected with the valve stem, and the seal is realized by two elastic sealing rings which are sheathed on the plunger. Two elastic sealing ring separated by a ring, and through the valve cover nut load exerted on the valve cover the periphery of the plunger sealing ring is tightly pressed by the. Elastic ring can be replaced, can be made of a variety of materials, the valve is mainly used for "open" or "off", but with a special form of plunger or special ring, can also be used to adjust the flow.
