Understanding the Different Types of Ball Valves

Ball valves are key components in many industrial processing operations. They are widely used to facilitate the transfer of liquids and gases across broad temperature and pressure ranges. They have a simple shut-off function to stop flow in a pipe, allow for hose connection and disconnection, divert, or alter flow direction.

As the name suggests, ball valves have an internal spherical disc structure referred to as the ball. The ball has a hole bored through its center which allows for flow. The ball is attached to a shaft. Turning the shaft 90 degrees opens and closes the ball. The advantage of a ball valve is they open and close to a positive stop, in other words you know when the valve is open and when it is closed. The direction of this movement is a full 90 degrees.

Ball Valves are reliable. They can repeat the same sealing function after many cycles and over extended periods of use.

There are several types of ball valves available in the market: 1-piece, 2-piece, 3-piece ball valves and available in various materials and sizes. So, what are the main differences between the different types?

Types of Ball Valves

Let us look at the various types of stainless steel (ss) ball valves commonly available:

• One Piece

Here the valve body is cast as a single entity. This means no joints in the valve body which effectively eliminates the risk of leaks. There is however a compromise in casting the valve body as a single piece as the ball will need to be inserted after the casting. The ball needs to be inserted through the threaded opening ends and hence will have to have a reduced diameter to fit through the threaded section. Referred to as reduced port. It is important to note that the internal diameter of the pipe decreases with the use of a one-piece ball valve. The size is reduced at the point of the one-piece ball valve, by one size. One piece ball valves tend to be used where particle build up is slow and cleaning is not an issue.

• Two Piece

This is the most common type of ss ball valve used. The body is cast from two pieces that thread together. The ball can be inserted directly in the larger cast body and is not limited by the threaded sections (so will be full port). These ball valve types are good for use with mixtures where optimal flow is preferred and cleaning may be a requirement. The removal of the attached threaded section of the valve body allows for cleaning and servicing of seals. You will need to remove the valve from the pipe to affect the cleaning, unlike is the case for the three piece (described below).

• Three Piece

The Three-Piece has a valve body cast out of three separate pieces: a body and two threaded ends. The threaded ends and body are held together by bolt connections fitted to each of the two ends. Like the two-piece, the three-piece allows for direct insertion of the ball in the larger ‘body’ section which allows for a larger ball and hence is full flow (full port). The design of this valve allows for the valve body to be removed whilst in situ. The valve is used where regular maintenance and cleaning is required. This makes them ideal for use in food and beverage applications and in pharma industries where sanitation and regular cleaning are key requirements.

• Three Way

These are multi-port valves that are used to mix and split flow (T-Port) and divert flow (L-Port). This is achieved by means of an L or T shape bore in the ball. More on these is a subsequent post. These are reduced port valves in a similar vein to the one-piece described above.

The Bottom Line

There are several types of ball valves available in the market, we specialise in supplying stainless steel ball valves, each with its unique set of characteristics best suited to individual requirements.

Understanding and recognising the different valve types helps operators choose the one most suited to their needs. So, explore all our products today at Camlock Fittings where we bring to market the best quality for price, industry standard fittings. We are the one stop shop for all your camlock fittings, camlock couplings, stainless steel ball valves, tri clamp and stainless threaded fittings. Contact us today to find out more!

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