Description
CF8 Gas Pressure Reducing Butterfly Valve (also known as flip valve) is a regulating valve with a circular valve disc or disc as the closing part. It is mainly composed of a valve body, a valve stem, a butterfly plate and a sealing ring. The valve body is cylindrical, with short axial length and built-in butterfly plate. The butterfly plate of the butterfly valve is installed in the diameter direction of the pipe. In the cylindrical channel of the butterfly valve body, the disc-shaped butterfly plate rotates around the axis, and the rotation angle is between 0° and 90°. When it rotates to 90°, the valve is fully open.
Main Features
1. The design is novel and reasonable, the structure is unique, the weight is light, and it can open and close quickly.
2. The operating torque is small, the operation is convenient, labor-saving and dexterous.
3. It can be installed at any location and is easy to maintain.
4. The seals can be replaced, and the sealing performance is reliable and achieves two-way sealing and zero leakage.
5. The sealing material is resistant to aging, corrosion, and has long service life.
Design and manufacturing standards
Design standards: GB/T12238-1989
Flange connection dimensions: GB/T9113.1-2000; GB/T9115.1-2000; JB78
Structure length: GB/12221-1989
Pressure test: GB/T13927-1992; JB/T9092-1999
Flange soft seal butterfly valves are suitable for air pipelines where the medium is water, oil, etc., such as metallurgy, chemical industry, electric power, municipal engineering, and water plants, and play the role of cutting off fluids and regulating medium flow.
Features:
1. This butterfly valve has a novel design and structure, small overall size and light weight.
2. The butterfly plate adopts double eccentricity, opening and closing quickly, and the operation is light and labor-saving.
3. The butterfly plate adopts double eccentricity, so that there is no sliding friction between the butterfly plate and the sealing ring.
The sealing surface is wear-resistant and has a long service life. The sealing is reliable and easy to adjust.
Butterfly valve flange types
Butterfly valve flange is called flange plate or flanged parts. It is a product that connects valves and pipes in pipelines. Butterfly valve special flanges are the same as ordinary flanges, but the inner holes are different. The special flange for butterfly valve has a small inner hole and an extra slot for pipe insertion.
Butterfly valve flanges can be individual or combined, such as flanges at both ends of the valve to facilitate the installation of bolts. The flange-to-flange connection between one end of the pipe and the other end, or the connection joint, refers to a foldable connection in which flanges, gaskets and bolts are connected to each other as a set of combined sealing structures. Pipe flanges refer to pipeline devices. The flange used for central piping refers to the flange of the valve. The flange has holes. Bolts tightly connect the two flanges, and the flanges are sealed with gaskets.
[Butterfly valve flange material]
NO. 20A,105,Q235A,12Cr1MoV,16MnR,15CrMo,18-8,321,304,304L,316,316L
[Sealing surface form]
Flat surface (FF), raised surface (RF), convex surface (M), concave surface (F), concave and convex surface (MF), tenon surface (T), groove surface (G), tongue and groove surface (TG), ring connection surface ( RJ).
[According to petrochemical industry standards]
Threaded flange (PT), butt welding flange (WN), flat welding flange (SO), socket welding flange (SW), loose flange (LJ), flange cover (not noted).
[According to machinery industry standards]
Integral flange, butt welding flange, plate flat welding flange, butt welding ring plate loose flange, flat welding ring plate loose flange, flanged ring plate loose flange, flange cover.
Basic knowledge
The flange butterfly valve introduces the self-sealing design concept, in which the connection between the valve disc and the valve shaft adopts a patented pull-out pin structure. The main features of this valve are reliable sealing, bidirectional sealing, and tight connection without loosening, making the valve long-lasting. Its characteristics are as follows:
Two-way sealing Usually, due to its structural reasons, traditional butterfly valves cannot seal well under the working pressure in the opposite direction (not conducive to the sealing direction). Currently, there are no mandatory provisions for bidirectional sealing in relevant national standards. This is because:
1. Adopt self-sealing design concept The valve disc sealing ring is directly embedded in the valve disc with rubber in a zigzag shape, without the need for pressure rings or bolts. This avoids the uneven stress on the sealing ring caused by the traditional bolt pressure plate seal, causing the bolts to fall off and the sealing ring to be damaged prematurely. The problem. Under the action of the working pressure in the opposite direction, the sealing ring generates a self-sealing force, which increases the sealing specific pressure and presses the valve seat tightly. The greater the working pressure in the opposite direction, the greater the self-sealing force, thus making the sealing ring and the valve seat The combination is tight and achieves a two-way sealing effect.
2. The valve disc has good rigidity and is not easily deformed. The valve disc of butterfly valve DN300 or above has a double flat plate truss flow structure, which has small flow resistance and good rigidity. It is not easy to deform under reverse working pressure, so that the sealing ring will not deviate from the best sealing point of the valve seat as the valve disc deforms. , thus ensuring the sealing effect of the sealing ring.
3. Rubber sealing ring has long service life (1) Due to the self-sealing design concept, the small interference between the rubber ring and the stainless steel valve seat only maintains the initial seal, so the specific pressure required for sealing increases as the system pressure increases. (2) In addition, there is a so-called "breathing" groove for the elasticity of the rubber to give way in the zigzag groove, so that the rubber has a certain expansion space when it is under pressure, so that elastic fatigue will not occur in long-term work, so the seal The life of the ring is greatly extended compared with traditional types.
