Butterfly valve is a open and close piece rotate with the pole to realize the start，close and adjust the valve， butter tly valve is used to not only shut and cut-off stream but also sealing.So that it is favored by the customers. in addition， the volume and the weight of butterfly valve is small and light， compare with various gate valve， the average weight is reduced 30%-50%， the butterfly pole wil open and close when it rotates 90℃.the open-close torque wll be small because the bearing of the butterfly plate is equal and the rotated torque is opposite. 

  One，the fiu oro plastic Lined butterfly valve series： 

1.The basic type isD71F.， D71F.，full liner butterfly valve，adopt two pieces of valve system combination when it works，the full plastic valve base and the liner plastic butterfly plate connect with the medium，the products wil be eroded by any of medium except the alkali metals and Teflon element.The valve poleD71F 46 connect with the butterfly plate，the surface cover FEP.The access of inside surface of valve is smooth，the low resistance and strong currency ability make the medium reach to class 4 sealing structure and ole resistant SI rubber flexible liner base so as to enable the zero-leakage of the medium. 

2.The above extended type D71FandD41F flange connect wth full liner，butterfly plate is stainless half line butterfly valve. 

Two.characteristic： 

1.Middle line butterfly valve possesses dual director sealing function and free pressure and flow adjustment with the base in a place of 360°concentric circle. 

2.The class 4loadflexiblesealng assure the inside and outside of valve zero leaking.a.axon and butterfly plate is special trans ii on curve connect with base of valve.b.the surface of axon adopt O circle and strong washer and flexible carbonated washer combination.c.the section direct of axle adopt O was er and metal was he combination.d.the base of valve is placed in the slot of flexible valve body. 

3.A or rect adjustable flexible orientation and brief of structure.(we adopt O circle to avoid unexpected leakage.) ； 

4.Flange dual eccentric butterfly valve is apply to the more high pressure occasion. 

Three、design standard：

The products adopt GB12238.API609 standard. 

Four、drive manner. 

Manual， worm gear driven，pneumatic-driven and motor-driven.