D371XThe worm gear clamp type soft seal rubber butterfly valve is a kind of valve which uses the worm wheel type opening and closing parts to rotate about 90 ° to open, close and adjust the fluid channel.
Butterfly valve not only has the advantages of simple structure, small volume, light weight, low material consumption, small installation size, small driving torque, simple and rapid operation, but also has good flow regulation function and closing sealing characteristics at the same time. It is one of the valve products with rapid development in recent ten years. Especially in the developed countries such as the United States, Japan, Germany, France and Italy, butterfly valves are widely used. The variety and quantity of butterfly valves are still expanding. They are developing towards high temperature, high pressure, large diameter, high sealing, long life, excellent regulating characteristics and multi-function of one valve. Its reliability and other performance indexes have reached a high level, and have partially replaced the stop valve and gate Valves and ball valves. With the progress of butterfly valve technology, butterfly valve will become the dominant valve form in a short period of time, especially in large and medium caliber, medium and low pressure applications.

Description of soft seal butterfly valve model preparation

Valve type	Transmission mode	Connection form	structural style	Sealing material	Nominal pressure	body material
D:butterfly valve	3:Worm gear	7:Clip on type	1:center line	X:rubber	-10:PN1.0MPa	Z: Gray cast iron Q: Ductile iron

 

The soft sealing butterfly valve is suitable for regulating flow and intercepting medium on water supply and drainage and gas pipelines of food, medicine, chemical industry, petroleum, electric power, metallurgy, urban construction, light textile, papermaking, etc
1. The design is novel and reasonable, with unique structure, light weight and quick opening and closing.
2. Small operating torque, convenient operation, labor saving and skillful.
3. It can be installed in any position and easy to maintain.
4. The sealing element can be replaced, the sealing performance is reliable, and the two-way sealing is zero leakage.
5. The sealing material has the characteristics of aging resistance, corrosion resistance and long service life.
6. It has the advantages of simple structure, good interchangeability and low price.
7. The valve stem seal is not easy to deform, so as to avoid the common phenomenon of valve stem leakage. The overall support is good, stable and firm.
8. It is easy to control the torque value in a proper range. It adopts two section valve rod without pin connection. The structure is simple and compact, and the maintenance and disassembly are very convenient.
9. The butterfly plate has the function of automatic alignment, which realizes the small interference fit between the butterfly plate and the valve seat. Phenolic back seat has the characteristics of no falling off, tensile, leak proof and convenient replacement. As the sealing surface of the valve seat is integrated with the back, the deformation of the valve seat is reduced.

D371XStandard for worm gear wafer type soft seal rubber butterfly valve

Design criteria	GB/T12238-2008、ISO 10631-1994orBS EN593-1998、BS5155、MSS SP-67
Flange connection
Structural length	GB/T12221 -2005、IS0 5752-1988SBSEN558-1
Pressure test	GB/T13927-2008、JB/T9092-1999、ISO 5028-1993orBS 5755-1-1986
Top flange	​Conform to is05211 and other standards

1. Before installation, check whether the specification, pressure, temperature and corrosion resistance of butterfly valve meet the use requirements. Check whether the parts are damaged or loose.
2. The butterfly valve can be installed on the pipeline at any angle and should be closed; when welding the pipe flange, the valve sealing port should be blocked with a plate to prevent particles and sundries from damaging the sealing surface. After welding, take down the valve, clean the valve sealing surface and pipe cavity, and then install the fixed valve.
3. Please pay attention to the pressure bearing direction when the valve is closed.
4. Before installation, the sealing surface (sealing surface at both ends, sealing surface of butterfly plate and sealing surface of valve seat) shall be thoroughly cleaned to remove dust and dirt.
5. Before installation, the butterfly valve should be air tested, and the opening and closing position should be flexible, and the opening and closing position should be consistent with the position indicated by the pointer.
6. Manual operation, clockwise is off, counter clockwise is on, pointer indication is in place, it is not allowed to open and close the valve with additional force.
7. During the pressure test of the valve, it is not allowed to use single flange for installation and pressure test, but double flange installation and pressure test must be adopted. The test pressure shall comply with GB / T13927-92.
8. The bolts shall be tightened symmetrically and alternately instead of separately.
9. The limit screw has been adjusted before delivery, so it is not allowed to adjust it easily. If the configuration of driving device is electric or pneumatic, please refer to the manual of supporting drive device.
10. When the electric butterfly valve leaves the factory, the opening and closing stroke of the control mechanism has been adjusted. In order to prevent the wrong direction when the power supply is connected, the user should first manually open it to the half open position before connecting the power for the first time, and then press the inching switch to check that the direction of the indicator wheel is consistent with the opening direction of the valve.
11. If the valve is found to be open and closed abnormally, the cause shall be found out for repair and elimination, so as to prevent the valve from being damaged due to opening and closing by means of applying force.

(1) Because the pressure loss of butterfly valve is larger than that of gate valve and ball valve, it is suitable for pipeline system with less pressure loss requirements.
(2) Since butterfly valve can be used for flow regulation, it is suitable to be selected in the pipeline that needs flow adjustment.
(3) Due to the limitation of structure and sealing material of butterfly valve, it is not suitable for high temperature and high pressure pipeline system. The general working temperature is below 300 ℃ and the nominal pressure is below PN40.
(4) As the butterfly valve structure length is relatively short, and can be made into a large diameter, so in the case of short structure length or large diameter valve (such as more than DN 1000), butterfly valve should be selected.
(5) Since the butterfly valve can be opened or closed only by rotation, it is suitable to select butterfly valve in the field with fast opening and closing requirements.