Swing Check Valve - Types and Features

A swing check valve stops backflow by opening with the forward current and shutting when the flow turns backward. It’s a kind of check valve built to let liquid move in just one way, automatically blocking any reverse movement. The main part of a swing check valve is its swinging disc, which lifts up when the liquid moves the right way and drops down to close when the flow goes the other way.

These valves work really well for managing strong horizontal streams. They’re commonly used in many fields like oil and gas work, water cleaning plants, sewer setups, and chemical production sites.

Swing check valves come in different kinds depending on their build and materials. Popular ones include full-port swing check valves, wafer-style swing check valves, and flanged swing check valves. Each kind is picked based on needs like pressure levels, space for setup, and the type of liquid being handled.

How a Swing Check Valve Works

An inline swing check valve has a disc that moves on a hinge. When it’s shut, the disc sits on the valve seal at the entry side of the valve.

When the force of the liquid coming in is stronger than the valve's cracking pressure, the disc lifts up. This opens the valve, letting the liquid pass through. But if the forward force falls below this point, or if there’s backward pressure, gravity or the reverse current pulls the disc back down to its seat. This blocks any backward flow.

This basic but strong design makes swing check valves a great pick for systems where stopping backflow is important, especially when fancy control systems aren’t an option.

Advantages and Disadvantages

Advantages

The hinge and disc setup is kept away from the main flow. This lowers the chance of thick or muddy liquids sticking to it and jamming the valve’s closing action. Swing check valves are made in big sizes. Their availability in larger widths makes them a good fit for big industrial jobs.

Disadvantages

Swing check valves don’t work well with flows that keep changing direction or have a pulsing pattern.These valves often face water hammer problems. You can lessen this by adding pressure relief valves before them or by planning pipe systems to avoid sharp turns in flow direction.

Materials

Brass body with NBR seal: Cost-effective, suitable for average heat and pressure.

Stainless steel with metal seal: Tough and corrosion-resistant; 316 stainless steel offers better chloride resistance.

Installation

A swing check valve is usually set up flat, in a horizontal position. It can go on vertical pipes if the flow moves upward. But, the disc might hit the seat hard when the flow stops, which could cause water hammer.

Steps to set it up include:

· Make sure there’s no dirt or junk inside the valve.

· Line up the valve right by pointing the arrow toward the flow direction.

· For threaded ends, use a wrench to tighten it. Don’t overdo it, as that can harm the valve.

· After setting it up, check for any leaks.

Spring Check Valve vs Swing Check Valve

The spring in a spring check valve manages the cracking pressure and closing action.

Main differences are:

· Spring check valves are somewhat better at handling water hammer. Swing check valves often struggle with this issue.

· Spring check valves can be placed in any position. Swing check valves are mostly used in flat pipe setups.

· Spring check valves generally cost more than swing check valves.

· Spring check valves allow less flow compared to swing check valves.

Deciding between the two should depend on your system’s design limits, noise worries, budget, and risk of water hammer.

Get The Best Swing Check Valve From FLUIDO

As a top maker and seller of steel valves, fittings, and flanges, FLUIDO has worked with over 35 countries and regions for more than 20 years.

FLUIDO provides a wide variety of top-notch products, including swing type non-return/check valves. All items meet tough global rules like ISO9001 certification by SGS and CE certification. For quality checks, every product is tested hard before shipping to ensure it works great in real conditions.

Whether you want standard sizes or custom designs made just for your needs, FLUIDO has you covered. Contact FLUIDO for more info and quote.