Manual Wafer Lining Rubber Soft Sealing Butterfly Valves D71X,D371X

The main structure of D71X and D371X manual clamp lined rubber soft seal butterfly valves is composed of valve body, valve disc, valve seat, valve stem, and transmission operating mechanism. The valve seat adopts a detachable structure, and corresponding materials that are resistant to high temperature, low temperature, corrosion, light, and aging can be selected according to the physical and chemical properties of different media. The inner and outer surfaces of the valve ductile iron shell can be coated with high-temperature electrostatic spraying epoxy resin powder coating, which has high corrosion resistance and extremely high bonding strength with the ductile iron matrix. The coating degree is 0.2-0.5mm. It is widely used in fluid pipelines such as water and electricity, sewage, construction, air conditioning, petroleum, chemical industry, food, medicine, light textile, paper making, water supply and drainage, as well as for regulating and intercepting flow, and can be changed by material, Suitable for different media such as water, gas, and oil, with a suitable temperature of -20 to 80 ℃. By replacing the valve plate sealing ring, O-ring, butterfly plate, shaft and other materials, it can be suitable for various media and different temperatures. The valve automatic control equipment is equipped with high-quality electric actuators or double acting pneumatic actuators, which can achieve automatic and manual dual opening and closing functions.

Execution standards:
Manufacturing standard: GB/T 122387-89
Flange standards: GB9113-2000, GB17241.6-1998
Structural length standard: GB12221-89
Inspection standard: GB/T 13927-92
Leakage rate: GB/T13927-92

Technical support for desulfurization butterfly valves:
Based on the analysis and research of desulfurization technology at home and abroad, as well as the introduction of desulfurization technology pilot plants in the domestic power industry, the current desulfurization methods can generally be divided into three categories: pre combustion desulfurization, during combustion desulfurization, and post combustion desulfurization. Among them, post combustion desulfurization, also known as flue gas desulfurization (FGD), can be divided into the following five methods according to the type of desulfurizer in FGD technology: calcium method based on CaCO3 (limestone), magnesium method based on MgO, sodium method based on Na2SO3, ammonia method based on NH3, and organic alkali method based on organic alkali. The commercial technology commonly used for desulfurization worldwide is the calcium method, which accounts for over 90%. Desulfurization technology can be further divided into wet, dry, and semi dry (semi wet) methods based on the dry and wet state of the absorbent and desulfurization products during the desulfurization process. Wet FGD technology uses a solution or slurry containing an absorbent to desulfurize and treat desulfurization products in a wet state. This method has the advantages of fast desulfurization reaction speed, simple equipment, and high desulfurization efficiency. However, it generally suffers from serious corrosion, high operating and maintenance costs, and is prone to secondary pollution. The desulfurization absorption and product treatment of dry FGD technology are carried out in a dry state. This method has the advantages of no wastewater and acid discharge, light equipment corrosion, no obvious cooling of flue gas during the purification process, high flue gas temperature after purification, favorable diffusion of chimney exhaust, and less secondary pollution. However, it has problems such as low desulfurization efficiency, slow reaction speed, and large equipment. The semi dry FGD technology refers to the flue gas desulfurization technology in which the desulfurizer is desulfurized in the dry state, regenerated in the wet state (such as the water washing activated carbon regeneration process), or desulfurized in the wet state, and treated with desulfurized products in the dry state (such as the spray drying method). Especially in the wet state, the semi dry method for desulfurization and the treatment of desulfurization products in the dry state has attracted widespread attention due to its advantages of fast wet desulfurization reaction speed and high desulfurization efficiency, as well as the advantages of dry method without wastewater and acid discharge, and easy treatment of desulfurization products. According to the use of desulfurization products, they can be divided into two types: abandonment method and recovery method.

Product features:

1. Flexible selection of operating mechanism for butterfly valves;
2. The butterfly valve has a beautiful appearance and good corrosion resistance;
3. Reasonable design, compact structure, simple installation and disassembly and easy maintenance;
4. The flow characteristics of the valve plate sealing surface are linear, with a small flow resistance coefficient, resulting in a small valve flow resistance;
5. The rubber sealing surfaces on both ends of the valve protrude from the ductile iron flange surface, and the valve does not require additional rubber sealing gaskets during pipeline installation;
6. Adopting a medium linear structure with no eccentricity design, it has a significant feature of low operating torque and significant economic efficiency when configuring electric devices;
7. Adopting a rubber lined structure, the butterfly plate’s circumferential sealing surface is precision machined to a high smoothness, resulting in extremely low friction coefficient for the rubber valve seat and a longer service life of the valve;
8. The uniquely designed molded rubber valve seat has excellent balance and support, effectively avoiding damage to the rubber caused by uneven force. When the valve is in the fully closed position, the rubber is in the best compression state to maintain zero leakage.

Main components:
Valve body: gray cast iron, ductile iron, carbon steel
Disc: carbon steel coated with rubber, carbon steel coated with fluoroplastics, stainless steel duplex stainless steel plates 1.4529, 2507, C276
Valve seat: natural rubber (NBR), ethylene propylene diene monomer (EPDM)
Valve stem: stainless steel, 2Cr13, 304

Product main external size:

Applicable situation for butterfly valves
Butterfly valves are suitable for flow regulation. Due to the significant pressure loss of butterfly valves in pipelines, which is about three times that of gate valves, when selecting a butterfly valve, the impact of pressure loss on the pipeline system should be fully considered, and the robustness of the butterfly plate to withstand the pressure of the pipeline medium when closed should also be considered. In addition, it is necessary to consider the limitations of the working temperature that the elastic valve seat material can withstand at high temperatures.
The structural length and overall height of butterfly valves are small, with fast opening and closing speeds, and good fluid control characteristics. The structural principle of butterfly valves is most suitable for making large-diameter valves. When using butterfly valves for flow control, the most important thing is to choose the correct size and type of butterfly valve so that it can work properly and effectively.
Usually, in throttling, regulating control, and mud media, short structural length and fast opening and closing speed (1/4 turn) are required. Low pressure cutoff (small pressure difference), it is recommended to use butterfly valves.
Butterfly valves can be used in channels with dual adjustment, contraction, low noise, cavitation and gasification phenomena, small leakage into the atmosphere, and corrosive media.
When using butterfly valves under special operating conditions such as throttling adjustment, strict sealing requirements, severe wear, low temperature (deep cold), etc., special three eccentric or double eccentric butterfly valves with specially designed metal sealing belt adjustment devices need to be used.
The mid line butterfly valve is suitable for fresh water, sewage, seawater, saline water, steam, natural gas, food, medicine, oil, various acid tanks, and other pipelines that require complete sealing, zero gas leakage during gas testing, high service life requirements, and operating temperatures between -10~150 ℃.
Soft sealed eccentric butterfly valves are suitable for bi-directional opening and closing and adjustment of ventilation and dust removal pipelines, and are widely used in gas pipelines and waterways in metallurgical, light industry, power, petrochemical systems, etc.
Metal to metal wire sealed double eccentric butterfly valves are suitable for urban heating, steam supply, water supply, gas, oil, acid-base and other pipelines as regulating and shut-off devices.
Metal to metal face sealed triple eccentric butterfly valves are not only used as program control valves for large pressure swing adsorption (PSA) gas separation devices, but also widely used in fields such as petroleum, petrochemical, chemical, metallurgical, and electric power. They are good substitutes for gate valves, globe valves, and so on.

The selection principles of butterfly valves

1. Due to the relatively large pressure loss of butterfly valves compared to gate valves and ball valves, they are suitable for pipeline systems with less stringent pressure loss requirements.
2. Since butterfly valves can be used for flow regulation, they are suitable for use in pipelines that require flow control.
3. Due to the limitations of the structure and sealing materials of butterfly valves, they are not suitable for high temperature and high pressure pipeline systems. The general working temperature is below 300 ℃, and the nominal pressure is below PN40.
4. Due to the short length of the butterfly valve structure and its ability to be made into a large diameter, it is advisable to choose a butterfly valve in situations where the structural length is required to be short or for large diameter valves (such as DN1000 or above).
5. Due to the fact that butterfly valves can be opened or closed by only rotating, it is advisable to choose butterfly valves in areas with fast opening and closing requirements.

Installation precautions:

1. Before installation, the specifications, pressure, temperature, and corrosion resistance of the butterfly valve should be checked to ensure that they meet the requirements for use. Each component should be checked for damage or looseness.
2. This butterfly valve can be installed on pipelines at any angle and should be closed for installation; When welding pipeline flanges, the valve sealing port should be blocked with a plate to prevent particles and debris from damaging the sealing surface. After welding, remove the valve, clean the valve sealing surface and pipeline cavity, and then install and fix the valve.
3. Please pay attention to the pressure direction when installing when the valve is closed.
4. Before installation, the sealing surfaces (sealing surfaces at both ends, butterfly plate sealing surfaces, and valve seat sealing surfaces) should be thoroughly wiped clean to remove dust and dirt.
5. Before installation, the butterfly valve should be air tested, with flexible opening and closing, and the opening and closing positions should match the indicated positions of the pointer.
6. Manually operate clockwise to close and counterclockwise to open. Do not apply force to open or close the valve after the pointer indicates it is in place.
7. When conducting pressure tests on valves, it is not allowed to use a single flange for installation and pressure testing. Double flange installation and pressure testing must be used. The test pressure should comply with the provisions of GB/T13927-92 standard.
8. When tightening bolts, they should be tightened symmetrically and alternately, and individual tightening in sequence is not allowed.
9. The limit screw has been adjusted before leaving the factory and should not be easily adjusted. If the drive device is configured as electric or pneumatic, please refer to the accompanying drive device manual.
10. The opening and closing stroke of the control mechanism has been adjusted when the electric butterfly valve leaves the factory. To prevent incorrect direction when the power is turned on, the user should manually turn it on to the half open position before the first power connection, then press the jog switch, and check that the direction of the indicator panel is consistent with the direction of the valve opening.
11. If the valve is found to have abnormal opening and closing, the cause should be identified for repair and elimination to prevent damage to the valve caused by using force to open and close the valve.