Valve Manufacturing 101 Understanding the Basics - Samco

Valve Manufacturing 101: Understanding the Basics

Read about the industrial valve manufacturing process, essential in controlling fluid flow and pressure in various processes or systems. It describes the difference between the cast and forged manufacturing methods and the stages involved in producing high-quality industrial valves.

Valves are mechanical devices constructed and designed to control fluid flow and pressure in a process or within a system. These key components of piping systems help convey liquids, slurries, vapors, and gases from one point to the other safely.

Industrial valves come in various shapes, sizes, and functions. Some examples of valves include the following:

  • Gate valve
  • Pinch valves
  • Safety valves
  • Ball valves
  • Check valves
  • Butterfly valves
  • Plug valves, etc.

Every industrial valve has several models, functional capabilities, and unique features. Some are self-operated, i.e. they don’t require human intervention while others can only be operated manually or with a pneumatic or actuator.

You are on the right page if you have ever wondered how industrial valves are constructed.

Understanding Valves

The top concerns of a pipeline process are service lifespan and safety. This is why high-quality valves are highly crucial when it comes to pipe systems. If you want to understand what makes high-functioning industrial valves perform impressively well during operations, knowing how they are made is essential.

The Industrial Valve Manufacturing Process

The focus will be only on the valve-making process. Industrials valves can be manufactured via 2 common methods: the cast method and the forged method. Let’s take a look at each manufacturing process.

  1. Cast Method

Here’s what the cast method of manufacturing industrial valves looks like. Bear in mind that this isn’t the complete process:

  • Body

It starts with cleaning an initial pre-shaped material, after which a turning process is performed. Turning is removing excess material via cutting using a turning or lathe machine. This involves attaching the cleaned, pre-shaped material to a mount and then to the lathe or turning machine.

The lathe or turning machine rotates the attached pre-shaped body extremely fast. During rotation, a single-point cutter slices the body into the desired shape. Turning can also create holes, grooves, etc.

Next, a plating metal – usually copper – is added to different sections of the pre-shaped body. Copper plating helps ensure proper and complete sealing of the body.

Polishing the body comes next. Technicians create the threads allowing the attachment of specific valve parts to the pipes or other vital components. Most valves come with holes so the holing process comes right after threading.

The requirement will determine the overall size of the hole created in the valves. Standards and regulations must be adhered to at this juncture.

Technicians paint the valves with Teflon or any other elastomer type. Baking ensues right after baking. Teflon or any other elastomer type used in painting the valve bonds with the valve body via baking.

  • Seat

The seat also goes through this entire process. Remember that the seat is inside the valve body and facilitates valve function, i.e. for better sealing. It must be a 100 percent perfect fit to its attachment. Even though the body is covered in Teflon, the seat ensures tight fitness as an extra rubber wrapping.

  • Stem

The stem doesn’t require much manufacturing. But it must be cut in the right dimensions.

  1. Forged Method

This method is as follows:

  • Cutting and Forging

After selecting the material, the next step is to cut them into the required widths and lengths. Then each part is forged by heating them partially to a particular degree.

  • Trimming

Trimming comes next, which involves removing excess materials. The body is then flashed to mold it into the ideal valve shape.

  • Sandblasting

This step makes the valve clean and smooth. The size of the sand used in this process depends significantly on standards or customer requirements. But before then, the valves must be sorted in order to get rid of defective ones.

  • Machining

This is where enhancing the shapes and sizes of threads, holes, etc., takes place. Once again, everything depends on the requirements and design the customer wants.

  • Surface Treatment

Treating the valve’s surface comes next and involves certain acids or solutions.

  • Assembly

This is where technicians attach every valve component. This is usually done by hand. The technicians assign the valves designation and valve manufacturing numbers according to the regulations in compliance with API or DNI.

  • Pressure Test

The valves undergo real pressure testing to check for leakage. Sometimes, air with 6 to 8 bar pressure fills up closed valves for several hours, ranging from 2 hours to a full day, depending on the valve size.

The valve is repaired immediately if a leak is detected after this timeframe. If not, the valve moves on to the next phase.

At other times, water pressure helps detect leakage. If the valve doesn’t leak as the volume of water is sufficiently increased, it has passed the test. This shows the valve can capably withstand increasing pressure.

Technicians may need to check for leakages before carrying out another set of pressure tests on other members of this batch of valves.

  • Inspection/Quality Control

This is where the Quality Control personnel exhaustively inspect the batch of valves for leaks or any other valve manufacturing errors that require correction.

If nothing is found and the valves are perfect, they have packaged accordingly and delivered to the client.

What Makes A High-Quality Valve?

But what makes a high-quality valve, you may ask? One defining factor for identifying high-quality valves is just the test of time. Long-service valves imply they are of excellent quality.

On the other hand, if the valve shows signs of internal leakages, it could mean that the manufacturing process or method employed did not comply with the required standard.

High-quality valves typically last as much as 5 years or even more, while poor-quality ones struggle to last 3 years.


As you can see, this is the ins and outs of valve manufacturing. It is a complex process, not as simple as outlined in this article. Several factors contribute massively to the efficiency of valves. The valves must undergo several rigorous tests to ensure proper and excellent function before being handed over to the customer who ordered them.