Seatless Butterfly Damper
The IVR model butterfly damper is a seatless butterfly valve intended for low pressure gas and air lines. The narrow wafer body means lightweight construction and this enables ease of fitting in ducts, manifolds, exhaust lines etc. without additional pipe supports or strengthening of pipework.
IVR valves are primarily intended for low pressure large volume gas flow control application. The absence of a seat substantially reduces valve operating torque and so makes the valve very effective for flow control / regulation duties. IVR is an ideal choice for furnace air flow and combustion control applications.
The body is designed for a maximum pressure of 2.5 bar with the maximum shut off pressure being 0.5 bar. The disc is held in position by an axial locking arrangement provided on the top shaft. The shaft sealing is through a stuffing box / gland which is site adjustable. .
Conformity to codes and standards:
| Actuator mounting bracket | ISO 5211 Part II |
| Valve inspection & testing | API 598 / ANSI / FCI: 70-2 (Class II) |
| Flange standard conformity | ANSI 150, DIN PN 6 / 10, BS 10 Table D |
Technical specifications
| Construction & Type | Centric disc, seatless butterfly damper |
| Body type | Narrow wafer single piece |
| End connection | Wafer sandwiched between flanges |
| Size range | 40 NB to 1200 NB |
| Maximum operating pressure | 0.5 bar (max) |
| Operating temperature range | -25C to 180C (Depending on MOC) |
| Operation | Manual or actuated with Pneumatic / Electric actuator |
| Available material of construction (MOC) | |
| Body/Disc | WCB / LCB/ CF8 / CF8M |
| Shaft | AISI 410 / SS 316 SH |
| Other materials available on request |
Dimensions
KEY FEATURES
Lightweight design suitable for mounting in ducts, exhaust lines and ventilation pipes.
Very low operating torque due to seatless construction.
Ideal for flow control / modulating duties in low pressure gas lines.
Very low pressure drop in open condition.
Wide operating temperature range to cater to exhaust & flue gas control lines.
Zero external leak due to the stuffing box type gland sealing arrangement.
Perfect adaptability for manual or actuated applications.