Variable Tandem Blowdown Valve Brochure

Variable Tandem Blowdown Valve

Traditional bottom blowdown service requires a tandem valve. Unlike older massive designs with limited serviceability, the CLAMPSEAL® unit tandem valve offers compactness, lighter weight and easy maintainability as well as longevity of service. These valves are suitable for steam drains or any high pressure letdown service.

Standard Size

Sizes through 4″”

Pressure Rating

ASME Class through 4500 #

Standard Forging ASME Materials

SA 105, SA 182-F22, SA 182-F91, SA 182-F92, SA 182-F316


Socket Weld, Butt Weld, Clamp Connector


Actuators – electric, pneumatic, or hydraulic
Limit switch – single or double
Locking devices – open, closed, both
Position indicator
Stem shroud

Design Features

Pressure Seal Bonnet

The simple and effective pressure seal bonnet provides ready access for servicing with no welds to cut or seal rings or gaskets to replace. The body-to-bonnet joint integrity is maintained through countless thermal cycles.

Single-piece Gland

In extreme environments, the simpler the design and the fewer the parts, the better. The durable single-piece stainless steel gland contributes to the longevity of the valve.

Axial-Loaded Packing System

The Axial design ensures tight concentricity, which eliminates side loading of the packing and minimizes wear forces on the trim components. This feature is critical for superior valve performance.

Pressure-Actuated Backseat

The Clampseal® pressure-actuated backseat provides maximum valve integrity by ensuring a positive internal stop for the valve stem and disc assembly. The pressure actuated backseat also extends packing life by securely isolating the packing from the pressure when the valve is fully open.

Rapid In-Line Renewability

The CLAMPSEAL® Valve is much easier to renew than anything else on the market. The CLAMPSEAL® Valve line provides a modular solution to rising maintenance expenses. Low acquisition cost is not as important as low cost over the serviceable life of a valve. Maintaining a Conval valve is far easier and much less costly than replacing a competitor’s valve.