Expansion Butterfly Valve

Introduction

An Expansion Butterfly Valve is a specialized valve designed to regulate the flow of fluids in piping systems, specifically in applications where thermal expansion and contraction of pipes need to be managed. The valve is typically equipped with an elastomeric seal and designed to handle large temperature fluctuations without compromising its sealing ability or performance. The expansion feature allows the valve to accommodate the expansion and contraction of pipes, ensuring tight shutoff and preventing leaks even as the system undergoes thermal stress.

Expansion Butterfly Valves are commonly used in industries where high temperatures and pressure variations are frequent, such as in power generation, oil and gas, chemical processing, and HVAC systems. The valve's robust design ensures efficient flow control while minimizing the risk of system damage due to thermal movement, making it a reliable choice for applications requiring durability and precise operation under challenging conditions.

Applications

Expansion Butterfly Valve is trusted across various industries for its precision, durability, and reliability. Explore its wide-ranging applications below:

Oil & Gas

Used to regulate the flow of oil, natural gas, and refined products in pipelines, the Expansion Butterfly Valve ensures tight sealing and efficient operation despite temperature fluctuations in high-pressure environments.

Power Generation

Employed in steam, feedwater, and cooling systems to regulate flow and maintain system integrity, even in the face of significant thermal expansion and contraction.

Chemical Processing

Handles the flow of chemicals and gases in pipelines, ensuring efficient flow control and a leak-proof seal in environments with extreme temperature variations.

Water Treatment

Used in water distribution systems and treatment plants to provide reliable flow control, accommodating temperature-related expansion without compromising seal integrity.

HVAC Systems

Installed in HVAC systems for regulating air or water flow, offering reliable sealing and flow control in heating, cooling, and ventilation applications under fluctuating temperatures.

Marine Applications

Used in marine and offshore systems for fluid flow regulation in ballast water, fuel, and cooling systems, ensuring efficient operation despite thermal expansion in harsh conditions.

Technical Specifications

Expansion butterfly valve integrates the functions of both flanged butterfly valve and pipe expansion unit, performed not only to throttle, but also to eliminate the internal force produced by temperature difference, namely the effect of expansion, It is used to adjust and cut off the flow of all non corrosive gas, liquid and semi liquid, as well as solid particle pipes and containers in the industries of electric power, metallurgy, petroleum, chemical, coal gas, heat supply, hydro power, papermaking, textile, medicine, foodstuff, water supply and drainage, energy sources and etc. Mounted randomly at any positions regardless of the types of medium and the direction of flow, it can also be used to adjust the space between the two flanges upon the installation of valve.

Features of Expansion Butterfly Valve

✔ Original design and distinctive structure.
✔Small sizes and light weight
✔ Labor-saving operation and quick open-close.
✔Adjustable and replaceable seal, dependable sealing, low fluid resistance and energy conservation

Installation Instructions of Expansion Butterfly Valve

✔Before installation, expansion butterfly valve shall be kept horizontally fiat and away from impact
✔The structural length of expansion butterfly valve is kept at the minimum upon going our of factory. To install, pull it to mounting length (namely designed length)
✔ In case of the space between pipes exceeds the length of expansion valve, adjust the space between pipes and never pull the expansion valve by force, as it may damage the valve
✔Adjustable and replaceable seal, dependable sealing, low fluid resistance and energy conservation
✔Expansion butterfly valve may be mounted at any position for the purpose of temperature compensation. After pipe has been mounted, put brackets at the two ends along with the pipe axial line, thus to prevent the expansion pipe of the valve from being pulled out (Fig. 1). The bearing force of brackets is calculated as the formula below. Never take the brackets off in service.
✔ $F = \frac{π}{4} \cdot PS \cdot {DN}^{2} \cdot (kgf)$
✔Test: PS-Test pressure of pipeline, DN-Diameter of pipeline
✔When expansion butterfly valve is not used for temperature compensation, but used only for convenience of replacement and repair, it can be limited by bolts that are symmetrically fastened to closely clamp the expansion butterfly valve, thus to prevent expansion pipe from being pulled out (Fig.2), as it may damage the expansion butterfly valve, pipeline or constructions. The diameter of bolts may be that of flange bolts. The bolt strength, bearing test pressure and pipeline tension may be calculated according to the formula above. Never take the limit bolts off is service. (Bolts are supplied otherwise).
✔Don’t dismantle the expansion butterfly valve on the pipe construction site
✔This butterfly valve is precisely machined and closely mated, adn shouldn’t be repeatedly pulled or pressed at random. Upon installation, the pipes at the two ends of expansion valve shall be kept concentric and the two flange faces on pipeline shall be parallel
✔This butterfly valve is precisely machined and closely mated, adn shouldn’t be repeatedly pulled or pressed at random. Upon installation, the pipes at the two ends of expansion valve shall be kept concentric and the two flange faces on pipeline shall be parallel
✔Expansion pipe is mounted behind valve.
✔ The expansion part of valve cannot be mounted at the corner or end of pipeline.