What are the types of globe valves?

During the opening and closing process of the globe valve, the friction between the sealing surfaces is small, it is more durable, the opening height is not large, the manufacture is easy, and the maintenance is convenient. It is not only suitable for medium and low pressure, but also suitable for high pressure.

How the globe valve works

The opening and closing parts of the globe valve are plug-shaped discs, the sealing surface is flat or conical, and the disc moves linearly along the center line of the fluid.
The closing principle is to rely on the pressure of the valve stem to make the sealing surface of the valve disc and the sealing surface of the valve seat closely fit to prevent the flow of the medium.
The globe valve only allows the medium to flow in one direction, and has directionality during installation. The structural length of the globe valve is longer than that of the gate valve, and at the same time, the fluid resistance is large, and the sealing reliability is not strong during long-term operation.

Classification of globe valves

Sort by channel direction

1. Straight-through globe valve

The medium inlet and outlet channels are in the same direction, at 180°, the degree of damage to the flow state is small, and the pressure loss through the valve is relatively small.

2. DC globe valve

The valve stem and the channel form a certain angle, the sealing surface of the valve seat and the inlet and outlet channels have a certain angle, and the fluid hardly changes the flow direction, which is the smallest flow resistance in the globe valve. Suitable for pipelines with coking and solid particles.

3. Angle globe valve

The medium inlet and outlet channels are not in the same direction, and are at an angle of 90°, which will generate a certain pressure drop. The biggest advantage is that it can be installed at the bend of the pipeline system, which saves elbows and facilitates operation.

Classification by thread position on the screw

1. Upper threaded stem globe valve

The valve stem thread is on the outside of the casing and does not directly contact the working medium, and the valve stem thread is not corroded by the medium, which is convenient for lubrication and labor-saving operation.

2. Lower threaded stem globe valve

The stem thread is inside the valve body and is in direct contact with the working medium. The stem thread is easily corroded by the medium and cannot be lubricated. It is mostly used in situations where the nominal diameter is small and the working temperature of the medium is not high.

Classification by use

1. Fluorine-lined globe valve

Fluorine-lined valve, also known as fluoroplastic lined corrosion-resistant valve, is a method of placing polytetrafluoroethylene resin (or profile processed) on the inner wall of a steel or iron valve pressure-bearing part (same method) by molding (or inlaying). It is suitable for the lining of various pressure vessels and pipeline accessories) or the outer surface of valve internals, and is made into various valves and pressure vessels by using its unique performance in resisting strong corrosive media.

Fluorine-lined globe valve The fluorine-lined globe valve is suitable for various concentrations of aqua regia, sulfuric acid, hydrochloric acid, hydrofluoric acid and various organic acids, strong acids and strong oxidants at temperatures of -50 to 150°C, as well as strong alkalis of various concentrations. It is used in pipelines of organic solvents and other corrosive gases and liquid media.

2. National standard globe valve

The national standard globe valve is the most commonly used product in the globe valve series. API American standard globe valve American standard globe valve implements ANSI and API standards. The sealing surfaces of the disc and valve seat are surfacing with Stellite cobalt-based carbide with different hardnesses. It has reliable sealing, high hardness, wear resistance, high temperature resistance, corrosion resistance, good scratch resistance and long service life.

3. Needle valve

Needle valve is a small diameter instrument valve, which plays the role of opening and closing and accurate flow control in the instrument measurement pipeline system, mainly including power station instrument series, oil field special series, American standard series, etc.

4. Low temperature globe valve

Cryogenic globe valve usually refers to the valve whose working temperature is lower than -110℃, which is widely used in liquefied natural gas, liquefied petroleum gas and other low temperature industries.

At present, globe valves suitable for temperatures up to -196°C can be manufactured, and all parts are pretreated with liquid nitrogen at low temperature to completely avoid seal deformation and leakage during use.

5. Plunger globe valve

Plunger valve Plunger valve, also known as plunger globe valve, its sealing surface adopts radial sealing structure, and the two elastic sealing rings sleeved on the polished plunger are applied to the valve cover through the connecting bolts between the valve body and the valve cover. The load compresses the elastic sealing ring around the plunger to achieve a sealed shut-off valve.

6. Insulation jacket globe valve

The heat-insulation jacketed globe valve adopts the design of heat-insulation jacket, which uses an external heat source to circulate and heat outside the valve, which can effectively prevent the temperature loss of the medium when it passes through the valve, and ensure the temperature of the medium.

7. Oxygen special globe valve

Oxygen special globe valve is made of high-quality silicon brass or stainless steel, which has the advantages of high mechanical strength, wear resistance and good safety.

Used on oxygen pipelines, it has the best explosion-proof and flame-retardant performance, eliminating the unsafe factors on oxygen pipelines, and is widely used in the pipeline network of steel, metallurgy, petrochemical, chemical and other oxygen-using projects. In addition to the functions of ordinary valves, it also has its own characteristics.

Strict oil-free measures are adopted during manufacture, and all parts are strictly degreased before installation.

8. Bellows globe valve

The bellows globe valve is designed with formed stainless steel bellows. The bellows reciprocates 10,000 times without failure, and the sealing performance is reliable. It is suitable for industrial and mining with flammable, explosive, toxic and harmful media, and can effectively prevent the valve from leaking.

The above is all the introduction about the types of globe valves. I hope to help you better. If you have any questions during use, please feel free to contact us.