AVT Composite Butterfly Valves

Double offset seat design and 360° bubble tight sealing and low operating torque with extended seat life and up to 60% weight saving versus metal valves!

Operator Design
Corrosion resistant lightweight, lockable levers with 7 intermediate stops are standard. Mounting accommodates ISO Standard gear operators and actuators.

Corrosion resistant stem extensions for buried service made to customer requirements.

Full Flange Face Body
For reduced flange cost. AVT Valves do not require the use of heavy duty flanges when used with GRE pipe systems. They can be fitted as direct replacements for metal butterfly valves of a similar specification. 

Available with plain holes (for through bolting) or with tapped inserts.

Disc / Seat Design
This disc design takes advantage of the inherent strength of all the resin systems to limit the overall thickness of the disc, thereby reducing the restriction of flow to a practical minimum when the valve is fully opened.

The seat is secured to the disc by a moulded retaining plate. Leakage behind the seat is prevented by a secondary seal moulded on the inside diameter of the seat.

Shaft Assembly
Our unique shaft/disc connection eliminates flutter for improved flow and noise reduction. Shaft designed as non-wetted, blow out proof.

First Degree Off-Set
The off-set between the seat face and the shaft axis makes the 360° seat possible ensuring bubble tight sealing even in high cycling applications.

Shafts
Sealed with a multi “O” ring system that ensures long life tight sealing even in high cycling applications without need for maintenance. Hastelloy® non wetted shaft as standard, with 316 and Titanium optional.

Second Degree Off-Set
The off-set of the shaft with respect to the axis of the bore combined with the first degree of off-set ensures that the sector of the seat sealing face is effectively cleared from contact by a very small angular motion. The introduction of this second degree of off-set reduces wear and break out torque.

METRIC DIMENSIONS (mm / kg)
Dimensions for ANSI 150 Butterfly Valves

IMPERIAL DIMENSIONS (inch / lbs)
Dimensions for ANSI 150 Butterfly Valves

 
Notes
1) Max WP for AVT 530 material, non-dangerous fluids at ambient temperature. AVT 520 is 80% of listed pressures. For other temperatures & fluids, please refer to Shipham Valves.
2) To allow for variations in break torque due to pressure and viscosity variations, it is recommended that actuators capable of developing forces a minimum of 30% greater than the above are used. Higher safety factors may be required in some applications e.g. when operations are infrequent.

Options

Note: Specifications are subject to alteration.