Single Plate Check Valves

SINGLE PLATE CHECK VALVES

A single plate is commonly known as a wafer check valve, swing check valve, or single disc check valve. They are designed to be used on flanges of standards ANSI, DIN OR JIS. It is a check valve type used mainly to prevent backflow in pipeline installation. The single plate check valve is available in sizes ranging from 1 1/2” to 6” and can withstand a working pressure of 232 PSI.

Made of Stainless Steel and CF8M, the single plate check valve has very high corrosion resistance. The connection types for a single plate check valve are JIS 5K Flange End, PN16 Flange End, ANSI 150# Flange End, and JIS 10K Flange End. The single plate check valve is made following the ASME B16.34 standards.

Material Specification	Stainless Steel / CF8M
Connection Type	PN16 Flange End JIS 5K Flange End ANSI 150# Flange End JIS 10K Flange End
Size	1 1/2” to 6”
Working Pressure	Up to 232 PSI

1. What are Single Plate Check Valves?

Single plate check valves are check valves designed to allow the flow of fluids in one direction. Also, Single plate check valves are made according to the ASME B16.34 standards and are compatible with connectors of ANSI, DIN, or JIS standards. This check valve's sizes are between 1 1/2” to 6” to enable it to fit into different systems.

The single plate check valves are made from stainless steel and CF8M materials. Single plate check valves are suitable for pipeline installation and enhance the flow of liquid and gases in the pipes. API 598 is the standard for testing the valve after production to ensure it meets the requirements and avoids damaging tools during operation.

The single plate check valves are compact and fit in a set of flanges. This makes it easy to install and clean during maintenance checks.

The table below shows the components and materials:

No.	Part Name	Material
1	Body	CF8M / SS316
2	Eye Bolt	SS316
3	Disc	SS316
4	Bolt	SS316
5	Washer	SS316
6	O-ring	VITON

2. What is a Single Check Valves used?

The single plate check valves work in a similar way to the swing check valve. The single plate check valve's complete set has about six components, which include the body, washer, bolt, eye bolt, disc, and O-ring. It’s important to state that single plate valves are classified as low pressure valves with a working pressure of 16 bars. The valve is made of a solid body with an inclusion of a thin plate profile placed in the middle, allowing easy installation with flanges. Flanges are devices that serve as connectors of pipes, tubes, and hoses to make up a piping system or attaching to a hydraulic system.

The single plate check valve's disc and seat perform a major function in controlling the flow of fluids. During operation, the fluids flow in a single direction and raise the disc from the valve seat. In a case where backflow occurs, the fluid flow drives the disc to the valve seat, leading to a closure of the valve and stoppage of fluid flow. The valve is being held in a significant position by the flange screws. Screw numbers depend on the size of the valve being used, and an O-ring seal applied on the valve keeps it free from external damaging factors.

Solid Body Single Door Check Valve

BAHASA INDONESIA

3. What are the differences between Single Plate Check Valves and Dual Plate Check Valves?

Check valves are automatic valves used in systems and pipeline installation to prevent backflow. They are designed to allow fluid flow in a single direction. Check valves are produced in different types such as swing check valves, dual plate check valves, lift check valves, etc. They are mostly preferred because it needs no workforce or supervision to fully operate and perform its main function which is to prevent fluid reversal.

Dual plate check valve also known as non-return valves performs the same function as the single plate check valves. They are used in low pressure systems to ensure no backflow of fluids during operation, and both are the most used check valves applied in several industries. With this similarity, these two check valves have some distinct distinguishing features, which are discussed below:

Slam: slamming is a major problem attributed to the check valves, however, the slam rate in each type differs. The problem occurs due to the rapid reverse flow stoppage when the valve closes, thereby leading water hammering and slamming. Single plate check valves are classified as the economical check valve type. It also slams more than the dual plate check valve. The dual plate check valve is designed with a spring that accepts the force of closure rather than hitting the seat.
Design: The dual plate check valves are more compact and lightweight than the single plate check valve. The disk weight is shared on the two parts instead of the entire weight resting on the single part on the wafer check valve.

The table below shows the major differences between the single and dual plate check valve:

Check Valve Design	Single Plate	Dual Plate
Unit cost	Lower	Higher
Body thickness	Thinner	Thicker
Unit weight	Lighter	Haevier
Disk body	One Disk	Two Disk

4. What do you need a Single Plate Check Valve?

SS316 Single Door Check Valve with Viton Seal

The benefits of the single plate check valve are discussed below:

Perfect operation and compatibility of use in both vertical and horizontal pipelines

Easy to use and install.
Light-weighted check valve
Durability and hitch-free operation
Valves' seats are produced using two O-ring material types, NBR, and viton seals.

The advantages of single plate check valves?

Compact size which makes easy to handle and weigh less
Streamlined flow passage
Ability to prevent backflow and automatic operation
Low pressure drop and minimized energy shortfall
Reduced slamming effect.

5. How is Single Plate Check Valve installed?

To ensure the single plate check valves' effective functioning, the installation has to be hitch and problem-free. Any mistake in the installation process could reduce the efficiency of the system or damage other components in the system.

For the right installation process, please refer to the details below:

Inspect the valve surface and O-ring materials for any contaminants. If found, clean thoroughly before installing it.
Check for the valve's compatibility in terms of pressure and temperature ratings, pipe measurements, chemical resistance, etc.
Using exits supports gives a higher opening angle for the single plate check valves.
Valves aren’t to be mounted precisely on the pump flange.
The single plate check valves are positioned in between two flanges and tightened with ring screws. The case's outer diameter and flange screws are two factors that determine the central position for placement.
The ring screw is placed on the top when installed on a horizontal pipeline.
The torque value should be considered when tightening screws.
After tightening, the tightness should be checked to ensure it falls on the standard scale.