1. Needle globe valve
It is used for accurate flow control. The valve disc is usually integrated with the valve stem, and it has a needle-like head that fits with the valve seat and has a very high precision. Moreover, the thread pitch of the stem thread of the needle globe valve is thinner than that of the ordinary globe valve. Under normal circumstances, the size of the seat hole of the needle globe valve is smaller than the size of the pipeline. Therefore, it is usually limited to use in pipelines with small nominal diameters, and more for sampling valves.
2. DC globe valve
The stem and the channel of the DC globe valve form a certain angle, the sealing surface of the valve seat and the inlet and outlet channels also have a certain angle, and the valve body can be made into an integral type or a separate type. The valve body split type globe valve uses two valve bodies to sandwich the valve seat, which is convenient for maintenance. This type of shut-off valve makes the fluid hardly change the flow direction, and the flow resistance is small in the shut-off valve. The valve seat and valve disc sealing surface can be surfacing with cemented carbide, which makes the whole valve more resistant to erosion and corrosion, which is very suitable for pipeline control in the alumina production process, and also suitable for pipelines with coking and solid particles.
3. Angle globe valve
The biggest advantage of the angle globe valve is that the valve can be installed at the corner of the pipeline system, which not only saves the 90° elbow, but also facilitates the operation. Therefore, this type of valve is more suitable for use in the synthetic ammonia production system and refrigeration system of the fertilizer plant. For example, J44H-160, J44H-320, L44H-160, and L44H-320 are completely designed for synthetic ammonia production system.
4. Steel ball or porcelain ball sealing globe valve
The structural feature of the valve is that the valve body is divided into one-piece and split-type, and the valve disc is made of STL hard alloy steel ball or a ceramic ball made of amorphous material through powder forming, high temperature sintering, and fine grinding. The lower end of the valve stem is rolled and enveloped in the ball hole of the valve stem. When the ball rotates three-dimensionally in the ball hole of the valve stem, countless sealing lines can be generated, which greatly increases the service life of the sealing surface and ensures reliable sealing. Due to the limitation of the ball seal, the valve is generally used for a smaller nominal passage, about 6-25mm. The valve is suitable for high temperature and high pressure steam pipelines of nuclear power plants and thermal power plants, instrument pipelines of sampling and sewage systems, and pipelines with temperature resistance, pressure resistance, wear resistance and corrosion resistance in petrochemical and chemical systems.
5. Globe valve for high temperature and high pressure power station
The structural feature of the valve is that the connection between the valve body and the bonnet adopts pressure self-tightening sealing type or clamp type, the connection form between the valve body and the pipeline is butt welding connection, and the valve body material is mostly chrome molybdenum steel or chrome molybdenum vanadium. Steel, the sealing surface is mostly surfacing hard alloy. Therefore, this type of valve is resistant to high temperature and high pressure, and has good heat resistance; the sealing surface is wear-resistant, scratch-resistant, corrosion-resistant, has good sealing performance and long service life. It is more suitable for pipelines of high temperature and high pressure, steam, oil and superheated steam in thermal power industrial systems, petrochemical systems and metallurgy.
6.API globe valve
This type of globe valve is designed in strict accordance with the ASMEB16.34 standard; the connection between the valve body and the bonnet, the installation of the stuffing box, the valve stem nut, and the upper seal are all designed in strict accordance with API600. The valve material selection fully complies with API600 requirements. The structural length conforms to ASMEB16.10; the flange connection dimension conforms to ANSI/ASMEB16.5a. The inspection and test of the valve are carried out in strict accordance with API598. Therefore, the valve is widely used in petrochemical pipelines, and also in electric power, metallurgy, textile and other systems.
7. Globe valve for oxygen pipeline
The valve is designed in strict accordance with the requirements of the oxygen pipeline. The stuffing box is strictly sealed, and external dirt cannot enter the stuffing box. The flanges at both ends of the valve body have grounding devices. After installation on the pipeline, they should be grounded to prevent static electricity from igniting. The shell material of this valve is austenitic stainless steel or copper, which has good electrical conductivity and is not prone to static ignition. The material sealed to the valve body is PTFE, which is a soft seal, with good sealing performance and zero gas leakage. The valve is strictly degreased by carbon tetrachloride before assembly, and there is no grease and dirt, which will not cause static fire. The valve is suitable for oxygen pipelines in metallurgical systems, and also suitable for oxygen pipelines in other industries.
8. Petroleum liquefied gas shut-off valve
This valve is specially designed for pipelines or installations of liquefied petroleum gas. The structure pays attention to fire protection requirements. The packing is made of polytetrafluoroethylene, which has reliable sealing and leakage. The sealing material is made of polytetrafluoroethylene or nylon for the body of the valve body, which is a soft seal with reliable sealing. This valve is suitable for liquefied petroleum gas pipeline system, as an opening and closing device, and also suitable for other pipelines whose temperature is less than or equal to 80℃.
9. Upper threaded stem globe valve
The stem of this type of globe valve is not in direct contact with the working medium. According to the shell material, sealing material, packing material and valve stem material, it is suitable for different working conditions. If the valve body and valve cover are made of carbon steel, the sealing material is alloy steel, the filler is flexible graphite, and the valve stem material is Cr13 series stainless steel, it is suitable for water, steam and oil pipelines; if the valve body and valve cover are made of It is 1Cr18Ni9 or 0Cr18Ni9, the sealing material is the valve body material or hard alloy, the filler is PTFE, the valve stem material is Cr17Ni2, it is suitable for the corrosive medium pipeline or device based on xiao acid; if the valve The valve cover material is 1Cr18Ni12Mo2Ti or 0Cr18Ni12Mo2Ti, the sealing material is the valve body material or cemented carbide, the filler is PTFE, and the valve stem material is 1Cr18Ni12Mo2Ti. It is suitable for corrosive medium pipelines or devices mainly composed of acetic acid. . However, the larger nominal diameter of this type of stop valve is 200mm, and the stop valve above 200 should be equipped with a bypass valve or an internal bypass structure in design. Generally, the inlet end of the globe valve with DN ≥ 200mm is above the valve disc, that is, high in and low out. This is to prevent too much effort when closing and the valve stem is too thick.
10. Lower threaded stem globe valve
The stem thread of this type of globe valve is in direct contact with the working medium, and is directly eroded by the medium, which makes the stem thread easy to corrode and makes it difficult to open and close. The nominal diameter of the globe valve of this structure is relatively small, generally between 6 and 50mm, and most of them are used in instrument valves and sampling valves.
11.API602 forged steel globe valve
This type of globe valve is designed according to the American Petroleum Institute standard API602. The valve body and bonnet are forged from carbon steel or stainless steel. The valve body and bonnet are connected by bolted connection, threaded connection and welding, with upper threaded stem and lower threaded valve. The rod is divided into, the sealing material is Cr13 steel, stainless steel acid steel to STL hard alloy, the filler is flexible graphite or PTFE, the connection methods are flange, thread, socket welding and butt welding, and the pressure level is CL150～ CL1500, the nominal pass through is 1/4 ~ 2in. It is widely used in equipment and pipelines in petrochemical, electric power, chemical and other departments. The working medium is steam, oil and corrosive medium. Structure The length is in accordance with ASMEB16.10, the flange connection size is in accordance with ASME/ANSIB16.5a, the welding end size is in accordance with ASMEB16.25, the socket welding hole size is in accordance with ANSIB16.11, and the threaded connection size is in accordance with ANSIB1.20.1.
12. Plunger stop valve
This type of plunger valve is a radial seal, which is realized by two elastic sealing rings sleeved on the polished plunger. The two elastic sealing rings are separated by a collar, and the elastic sealing ring around the plunger is pressed firmly by the load applied to the valve cover through the connecting bolt of the valve body and the valve cover to ensure the sealing. The material combination of the valve is carbon steel for the shell, Cr13 stainless steel for the plunger, and flexible graphite for the sealing ring. It can be used for water, steam and oil pipelines; if the shell is made of stainless acid-resistant steel, the plunger is made of stainless steel. Acid-resistant steel, PTFE for sealing ring, suitable for acid and alkali corrosive media. The advantages of the valve are reliable sealing, long service life and easy maintenance; the disadvantage is that the opening and closing speed is slow. This type of valve is widely used in urban construction systems, water and steam pipelines in urban heating.
13. Bellows globe valve
Bellows globe valve is also called bellows seal globe valve. Through automatic seam welding, a metal barrier is formed between the fluid medium and the atmosphere to ensure the design of zero leakage of the valve stem. The bellows globe valve adopts a bellows structure inside, and the lower end of the stainless steel bellows is welded to the valve stem to prevent the process fluid from eroding the valve stem. The other end is placed between the valve body and the valve cover to form a static seal. The double sealing design will avoid leakage if the bellows fails the valve stem packing. The bellows is welded to the valve stem to maintain stable operation performance and avoid the valve stem vibration caused by the valve plug vibration. More suitable for steam, flammable, explosive, heat transfer oil, high purity, toxic and other media pipelines.