Butterfly Valve Type 56
Materials  

Body
Lens
Gaskets

PVC - PP - PVDF
PVC - PP - PVDF
Sleeve type in EPDM - FPM
Diameters(*)
 From DN 40 to DN 400
Connections
Flanged DIN PN10 or ANSI 150 lb
Operation
Manual with lever up to DN 200 Manual with gear box from
DN 40 up to DN 400
Automatic with pneumatic or electric actuator

*) For diameters from DN450 up to DN600 Type 56 is available; over, up to DN1500 the model made in FRP (Fiber Glass Reinforced Plastic) is available

 

INNOVATIVE FEATURES

 

 We now consider in four points the peculiar and innovative features of the new Asahi butterfly valve made in PVC, PP, PVDF from DN 40 to DN 400

 

1. MODULAR DESIGN OF THE STEM AND OF THE TOP FLANGE


Without any modification, Type 56 butterfly valve can be changed form manual with lever to manual with gear box or can be easily automatized with pneumatic or electric actuator. The top flange drilling, the length and the square of the stem remain the same.

 

 

2. NEW DESIGN OF THE TOP FLANGE

The drilling of the top flange is made according to ISO 5211 standard. This aspect allows the easy mounting of pneumatic and electric actuators with a standard bracket.

 

 

3. NEW DESIGN OF THE LEVER

Here follow the new characteristics of the new handle lever:
- Better handgrip. - No metal parts.
- Regulation in 19 steps (every 5°).
- Sure holding of the position and High resistance to the torsion.

 

 

4. HIGH PERFORMANCES

From the comparison tests the following characteristics appears:
- Very good sealing under pressure.
- Long holding of the perfect sealing (comparison tests up to 20.000 cycles) as it is shown in the graphic (a).
- Low stem torque for the perfect closing and for the opening. Finally, it must be noted that the sleeve gasket makes needless the use of the flat gaskets between the valve and the stubs.

a) DURABILITY TEST ON WEARING OF THE GASKET

- Repeat opening and full closing up to 20.000 cycles.
- Every 5000 cycles check the seal performance on the valves.
- The result points out how after thousands cycles the sealing is kept constant for the valve Type 56 (red line).