Introduction to a ball valve?
A ball valve is a mechanical device that controls the flow of various substances by rotating a ball-shaped disc. Examples of multiple substances are gases, pressure, liquids, and other things. It’s open when the ball’s hole lines up with the flow entry. It’s closed when the valve handle rotates through 90 degrees, blocking the flow. When the valve is open, the handle is flat in line with the flow, but it is perpendicular to it when closed. It allows for simple visual confirmation of the valve’s condition. The 1/4 turn in the closed state has two ways—clockwise or counter-clockwise.
Types of ball valves:
Following are the basic types of ball valves based on ball movement.
· True union port ball valve
· Floating valve
· Manually operated ball valve
Floating ball valve:
The compression of the two elastomeric seats against the ball keeps the ball in a floating ball valve. Inside the valve body, the ball can freely float. This is one of the most popular ball valve designs. A stem connected to the top of the ball makes a quarter rotation. Besides, the seat improves leak protection. Due to its design, the floating type is clickable in both directions (on and off).
True union ball valve:
True union ball valves contain a pin that holds the ball in place and prevents it from moving. Trunnion has two shafts at opposing ends of the ball. It allows the valve to support a segmented ball and reduce friction between the different components.
The true union can withstand more pressure than a regular ball valve. Thus, it is applicable in a high-velocity system.
The design of the trunnion ball needed a lower working torque. As a result, the actuator’s size and total valve expenditures are reduced. The cost difference becomes more significant when the pressure class and valve size grow.
Manually operated ball valve:
By definition, manual valves use a manual operator (such as a hand wheel or hand lever) to stop and start flow (block or on-off valves). Specific designs, meanwhile, are also used for simple throttling. The most delicate manual valves for on-off service enable flow to go through the body. Also, have a full-area closing element with little pressure drop. We use a manual valve to start and stop the flow; the partial flow is a throttling valve. The manual operator is in the middle of the stroke as an on-off valve.
Apart from the above types of ball valves, we have the following ball valves.
Types based on a number of the pieces:
When we talk about the number of ball valves, there are three pieces, two pieces, or unibody.
One Piece Ball valve:
In contrast to the two and three-piece ball valves, the One Piece Ball valve has only one body piece. It indicates that cleaning the valve is difficult. The valve will be low-cost and durable, which is a benefit. A one-piece valve body necessitates using a smaller ball, resulting in a decreased port, also known as a reduced bore, as the ball hole is smaller than the pipe diameter. The flow through the valve is restricted. A solid cast body decreases the danger of leaking in one-piece ball valves. They’re cheap and don’t need
repairing very often.
two-piece ball valves:
Some of the most popular ball valves are two-piece ball valves. The two-piece ball valve, as its name implies, is two pieces. One part is linked to one end and the other to the body. The second part fits into the first, secures the trim, and has the second-end connector. Once installed, these valves are usually not repairable until they are out of operation.
Three-piece ball valves:
Three-piece ball valves consist of two end caps and a body. The end caps are usually threaded or welded to the pipe. The main body part may be fully detached for cleaning or repair without removing the end caps. It can be a very suitable choice since it prevents the line from shutting down for repair. Even during field repairs, they provide excellent seat alignment with the ball.
Types based on body arrangement:
Ball Access: Side entry or top entry. It depends on whether the ball can be accessible from the valve’s side or its top for maintenance.
Split body ball valve:
There are two parts to this split body ball valve, one smaller than the other. A ball, seat rings, stem, and other internals are inside the larger body part. The ball is present in the bigger body part.
Top entry ball valves:
The valves that construct the ball from the top end are top-entry ball valves. It’s like a globe valve; it has a body and a cap, but the trim comes from a ball type. It is from a single entity. The top entry ball valves are usually composed of cast metal. It’s made of cast metal, so further NDE testing ensures the casting process is defect-free.
The top Ball valve is used in oil: gas pipelines, oil machinery, and refining with different applications. Also, petrochemical chemical, chemical, metallurgical, nuclear, food, and paper industries require this tool.
Welded Body Ball Valve:
Welded Body Ball Valve has a forged steel body, also known as a Fully or complete Welded Ball Valve. The complete welded body assures that the valve body has no external leakage paths. To do the valve body welding, we use non-destructive testing. A full welded is usable for a long and repeatable time. It requires regular maintenance and is simple to set up. Manual or electric drive modes are available for complete welded ball valves. Butt welding helps join full welded ball valves.
Types based on valve opening:
The number of ports classifies ball valves. There are 2 ports on a typical ball valve (1 inlet and 1 outlet). A 3-way port can have 1 inlet and 2 outlets, or 2 inlets and one exit.
V-Port Ball Valve:
In the V-port ball valve, the V shows the seat’s form or the ball’s shape. We can better manage the opening and shutting using a V-ball valve. This flow has a linear flow characteristic because of the high velocities of the fluids used with these ball valves. The designers had to develop a more durable design since these fluids may harm a regular valve.
Standard Port Ball Valve:
The standard port ball valve has a small port and ball than the full port ball valve. It is less costly, but owing to the pipe size, it has a little restricted flow. Although standard ball valves are cheaper, they have greater pressure drops than others. Like full port valves, standard port valves are ideal for systems with a high flow coefficient.
Standard port valves contain smaller bodies and a narrowing of the valve body inside.
Full port ball valve:
The cost of a full port or full-bore ball valve is higher than that of other designs. As the hole in the full port ball valve is the same size as the pipeline, the bigger ball reduces friction loss. The flow is not controlled at full port ball valve size despite the valve being greater.
Full-bore ball valves handle throttling applications in diverse systems. This is possible with high flow coefficients and moderate pressure drops.
Reduced-port ball valves:
Reduced-port ball valves, also known as RBs, have less flow area than the pipe. Flow through the valve that is one pipe size smaller than the valve’s pipe size. This sort of ball valve caused a decrease in pressure in the pipeline. A 3/4″ reduced port valve has a 1/2″ pipe-size ball opening. The more compact body will lead to low prices. As a result, if such applications do not have a tight flow rate need but have a higher material need. The reduced port ball valve is a cost-effective option for a complete stainless body.
A 3-way ball valve:
A ball valve usually has two entrances (or “two ways”).
A 3-way ball valve is for a specific application. Instead of two ports (entries), a 3-way ball valve has three. This multi-port design redirects fluid from the primary valve input in two directions. Another common use for a 3-way ball valve is two distinct and alternate inlets supplying the main flow line. The ball of a three-way ball valve is available in either an L or a T shape. This specific form of ball valve is also available in a floating or trunnion—design with any valve end (flanged, socket, or threaded connection). And in various materials, from plastics to carbon, alloy, and stainless steel.
Multi-Port Ball Valve:
Ball valves having three or four ways and an L to T-shaped hole in the center are multi-port ball valves. T valves link any two ports, whereas the L valve connects the central port to the side ports. The inlet is orthogonal to the outflow plane in a multi-port ball valve. The X port on 4-way ball valves is a 2L-shaped opening in the ball.
Types of the ball valve based on the material used:
This section will cover the types of ball valves based on material.
Polyvinyl Chloride ( PVC )is a plastic used to make PVC ball valves. One of its benefits is that they are flexible and smooth. It allows ball valve parts to move more. It’s best suited to low-pressure applications.
Stainless steel valves:
Stainless steel valves have significant advantages, such as corrosion resistance and durability. This ball valve plays an essential part in geochemical systems and other general plants due to the vital qualities of stainless steel. For the medium quality, we use stainless steel grade 314.
Bronze and brass:
Bronze and brass valves are ideal and are used in systems under low or medium pressure. Plus, these valves are water and corrosion-resistant. Brass material is like bronze in its machinability, but brass is cheaper than bronze.