Ceramic Ball Valve 

What is a ceramic ball valve?

A ceramic ball valve is a type of ball valve which has internal components made of ceramic materials. Such ceramic components include ball, seat, and lining. A ceramic ball valve has its body made of a metallic material such as stainless steel or carbon steel. The metallic body is used to protect the ceramic trim from damage by sudden mechanical or thermal shock. A ceramic ball valve uses a ball with a hole at its center where fluid flows through when the handle is rotated. Ceramic ball valves can also be automatic by using actuators like pneumatic, electric, or hydraulic actuators. Benefits of using a ceramic ball valve over other materials like steel include lower mass and high resistance to wear. Ceramic ball valves have excellent resistance to corrosion and abrasion. Such properties of ceramic ball valves are used in severe applications prone to abrasion and corrosion. Ceramic ball valves are used in various industries such as petroleum, chemical engineering, and manufacturing plants. 

Figure: Ceramic ball valve.

Components of a ceramic ball valve 

Handle/actuator 

The handle is a component of a manually operated ceramic ball valve where the valve operator applies torque to open or close the valve. The actuator is used in actuated ceramic ball valves and it provides the torque required to open or close the valve as well as providing the intelligence for automation. 

Valve body 

This is the component of ceramic ball valve used to house all internal parts of the valve. The valve body is made of strong metallic materials such as carbon steel and stainless steel to provide high mechanical strength to the valve so that it can withstand high pressure and impact damage. The valve body contains the inlet and outlet port of the ceramic ball valve. 

Stem 

This is the component of a ceramic ball valve that is used to transmit torque from the handle/actuator to the ball. The stem connects the actuator/handle to the ball. 

Ball 

The ball is the component of a ceramic ball valve tasked with opening and closing fluid flow. The ball is connected to the handle or actuator via the stem. The ball has a bore at its center where fluid flows through the valve when in an open state. 

Seats

These components are placed between the ball and the valve body to support the ball and also prevent fluid leakage. 

Trim 

Trim refers to the internal components of the ceramic ball valve that comes into contact with the fluid such as the glands, O-rings, and seats. 

Gland packing 

This is the component of the ceramic ball valve used to provide a seal between the stem and the valve body to enhance the fluid-tight seal around the handle and stem assembly. 

Figure: Components of a ceramic ball valve.

How does a ceramic ball valve work?

 Ceramic ball valve is used for on and off fluid flow applications. The ability of a ceramic ball valve to open and close fluid flow is enhanced by the use of a ball with a bore at its center. The ball is connected to the valve handle or actuator through the valve stem. The ball is responsible for closing and opening the fluid flow through the valve. The fluid flows through the ceramic ball valve through the ball bore. To start a ceramic ball valve, the handle (for manual ceramic ball valves) is rotated for 90^o degrees in the anticlockwise direction. This makes the valve stem and the ball rotate at the same 90^o degree angle. When the ball is rotated for that 90^o angle it makes the ball bore become in line with the pipeline. This makes the fluid flow through the ceramic ball valve and the valve is said to be in an open state. To close the ceramic ball valve, the handle is turned in the clockwise direction which makes the ball bore turn and become perpendicular to the pipeline and thus the ball blocks the fluid flow. The same working principle is employed in ceramic ball valves operated using an actuator. The only difference is that the actuated ball valve gets its torque from an actuator, unlike the manual ceramic ball valve which gets its torque from the valve operator. 

Figure: Working of a ceramic ball valve; open valve (left side) and closed valve (right side).

Types of ceramic ball valves 

Two-piece ceramic ball valve 

This is a ceramic ball valve made up of two pieces of the body fitted together. One-piece contains one end connection and the ball and the other piece contains the internal parts and the other end connection. The two-piece ceramic ball valve is very common among ceramic ball valves. A two-piece ceramic ball valve can be dismantled for inspection, cleaning, and repair. However, a two-piece ceramic ball valve needed to be removed from the pipeline before it is dismantled for cleaning or repairs. 

Three-piece ceramic ball valve 

This is a ceramic ball valve made up of three pieces that is two end parts and the valve body. The three-pieces of this ceramic ball valves are connected using bolts and nuts. A three-piece ceramic ball valve makes it possible to remove the center parts of the valve that is ball, seats, and stem while the valve is attached to the pipeline. This helps in cleaning clogged solids, replacement of gland packing and seats, and polishing scratches on the ball without the need to remove the ceramic ball valve from the pipeline. Three-piece ceramic ball valves are very expensive relative to their two-piece counterparts. 

Three-way ceramic ball valve 

This is a ceramic ball valve with three ports. Three-way ceramic balls can have T-shaped or L-shaped configurations. Three-way ceramic ball valves are used in industries to mix or divert fluid flows. The L-shaped configuration is used to divert fluid. In an L-shaped ceramic ball valve fluid from one port is diverted into one of the ports at an angle of around 90^o directing it to another pipeline. The T-shaped ceramic ball valve can be used to either mix or divert fluid streams. When used to mix fluid streams, the T-shaped three way ball valve uses two fluid streams which are mixed to form one fluid stream through the outlet port. When a T-shaped ceramic ball valve is used to divert fluid streams from one port into two or one of the three ports as it may be required. 

Figure: Three-way ceramic ball valve.

V-port ceramic ball valve 

This is a ceramic ball valve with a V-shaped ball bore or valve seats. Ceramic ball valves with V-port help to precisely control the fluid flow rate by rotating the ball. V-port ceramic ball valves can be optimized to enhance a flow of linear characteristics. The v-port ball valve can better control fluid flow relative to other ball valves. This is because when the ceramic ball valve is opened the small end of the “V” port opens first which allows stable fluid flow control. A V-port ceramic ball valve needs a strong design because of the high velocity of the fluid which if not strong enough can damage a standard ceramic ball valve. V-port ceramic ball valves which have been designed well can be used to control fluid flow. 

Figure: V-port ceramic ball valve.

Features of a ceramic ball valve 

High strength 

Ceramic ball valve internal components are designed and manufactured using high-performance structural ceramic materials. The body and external parts of the ceramic ball valve are manufactured using high-strength metallic materials which enhance its mechanical strength. 

Durable 

Ceramic ball valves have good abrasion resistance, corrosion resistance, and high metallic body strength. Under the same working conditions, the service life of a ceramic ball valve is 2 to 4 times that of other corrosion and abrasion-resistant valves. 

Corrosion resistance 

Ceramic ball valves have stable chemical characteristics for most acid-based fluids which makes them excellent for corrosion resistance. 

High hardness value 

Ceramic ball valves as the name suggests are made of ceramic materials which are known for their high hardness. Such ceramic materials include zirconia which has a high hardness value of around HRA88 which is second after the strongest material diamond. 

Need low torque 

Ceramic ball valves have a smooth surface of the seat and ball and a self-lubricating feature when opening and closing. This makes the opening and closing resistance small and thus needs small torque to open and close. 

Free from fluid leakage 

Ceramic ball valves use a surface contact sealing between the ball and the seat. The sealing contact is enhanced by the high accuracy roundness of the ball which ensures that it can produce zero leakage as per international standards. 

Applications of ceramic ball valves 

• Chemical industries to transfer fluids like acids, and polymer slurries among others. 
• They are used in production of fertilizer products such as phosphoric acid, amine nitrate, and phosphate, among others.
• Pulp and paper-making industries to control the flow of fluids such as bleaching agents, and paper fillers among others. 
• Drainage and water supply systems. 
• Food and beverage industries. 
• Pharmaceutical applications. 

Advantages of ceramic ball valves 

• Easy to operate. 
• They need small torque to open and close. 
• They are versatile valves. 
• They are very durable. 
• Resistant to abrasion. 
• Resistant to corrosion. 
• Ceramic ball valves can be inspected, cleaned, and repaired. 
• These valves are free from leakage. 
• They have high strength for high-pressure and high temperature applications. 

Disadvantages of ceramic ball valves 

• Close very quickly which may cause overpressure and hammering problems. 
• The trim components have low toughness making them susceptible to damage. 
• Not suitable for throttling applications.

Troubleshooting ceramic ball valves 

Ceramic ball valve leaking fluid when closed 

• Damaged ball. Replace the ball. 
• Damaged seats. Replace the seats. 
• The ball is not fully closed. Check the opening or closing settings of the ball.

Irregular ball movement 

• Sediments between the seat and the ball or between the ball and the valve body. Clean the inside of the ceramic ball valve and seal surfaces and if necessary replace the seats. 

Very high torque to open or close the ceramic ball valve

• Foreign materials in the valve. Remove the materials. 
• High pressure and or temperature. Ensure the valve is working for the recommended pressure and temperature rating. 
• The seats are damaged. Replace the seats. 

Ceramic ball valve having a noisy operation or water hammer 

• Fluid flowing at very high velocity or wrong valve sizing. Ensure the valve and fluid flow rates are as recommended by the ball valve manufacturer. 

Steam leakage 

• Loose gland cap screw. Tighten the gland screw. 
• Damaged stem seal. Replace the stem seal. 

Summary 

A ceramic ball valve is a type of ball valve that has internal components that is seats, ball, and lining made of ceramic materials. The external part is made of strong metallic materials such as stainless steel and carbon steel. The metallic materials are meant to provide high strength against high pressure and high temperature as well as impact resistance. Ceramic ball valves work by using a ball with a bore at the middle section. The fluid through a ceramic ball valve flows through the ball bore. Ceramic ball valves can be operated either manually or by using an actuator. Ceramic ball valves are of various types which include v-port ceramic ball valves, two-piece ceramic ball valves, three-piece ceramic ball valve, and three-way ceramic ball valves. The applications of ceramic ball valves include chemical industries, fertilizer production, drainage, and water supply, food and beverages, pharmaceuticals among others. The advantages of ceramic ball valves are durable, versatile, and quick in operation, low operating torque, resistant to abrasion and corrosion, leakage free and they are repairable.