WHAT IS A BALL VALVE?

A ball valve is described as a mechanical device that directs, guides and modulates the flow of various types of liquids by way of an opening of a ball which has an opening in the middle. The opening is referred to as the port. By turning the handle on the ball valve, this manually opens/closes the port which controls the pressure from the flow of the liquid. Durability and “perfect” shutdown/shutoff are what makes the ball valve advantageous over other type of valves.

Valves are found in our everyday living and may go unnoticed. For example, there are plumbing valves which are at our sinks in our spigots. There are valves inside our washing machines, dishwashers, gas fireplaces, outside water spigots, refrigerators and more. Various types of industries utilize valves for their productions. Such industries include electronics, power, automotive, printing, plastics, textiles, metal, medical, chemical and food, to name a few. The industries that utilize ball valves typically have a need for supporting high pressure and temps exceeding 480 degrees. Ball valves are simplistic to operate and repairs are made easily without being removed from their pipeline.

Being made of steel, brass, iron, bronze or PVC, ball valves can range in sizes from .2 to 11.81 inches. More complex control systems using valves that need to regulate flow through a pipe will need an actuator. The actuator controls the valve pneumatically or is motor-operated and keeps it positioned appropriately so that the flow of the liquid is precise to the changing pressures and flow levels.

The basic types of ball valves include Full Port, Reduced Port, V-port, Multi-port, Standard Port and Cavity Filler ball valve. There are 3-way and 4-way ball valves. Depending on the application would determine the type of ball valve being used. The specifications to be considered for determining the appropriate ball valve would be the temperatures and pressure, number of ports, valve size, type of body material, end connectors and configurations.

 

Sourced by ekomeri.com

The post WHAT IS A BALL VALVE? appeared first on KST Plant.

Soft Seated or Metal Seated Ball Valves?

 

There are two types of seat in a ball valves, soft seated and metal seated. Soft seated ball valves use a thermoplastic material such as PTFE, NBR etc. Metal seated ball valves use metal as seat material such as 316 SS, monel, etc. Each ball valve seat type has its own characteristic and thus having its own advantages and disadvantages. So how to select the best ball valves seat type?

In general application the soft seated ball valves is suitable for a clean fluid and not recommended for a dirty fluid. This is reasonable since some particulate may damage the soft seat material and causing a leakage. In dirty fluid application, the metal seated ball valve is the best choice.

The metal seated ball valve is also suitable for application that has a high erosion or corrosion rate. The metal ball valve will stay much longer than soft seated ball valve in such application. In term of the shut-off capability, the soft seated ball valve is the best. It can achieve the highest level of the seat leakage class while a metal seated ball valve can achieve only up to ANSI/FCI Class V or ISO 5208 Rate D. Thus if the tight shut-off or bubble tight shut-off is required, then there is no choice except using the soft seated ball valves.

In term of the required torque to operate the ball valves, the soft seateThe metal seated ball valve is also suitable for applicationd ball valve will have a lower torque rather than metal seated ball valves. The high torque of the metal seated ball valve may lead the selected actuator model is bigger than the soft seated ball valve thus it increase space consumption and add additional weight.

In general practice, a metal seated ball valve is only used in the severe service condition such as high temperature, high erosion or abbrasion, slurry, etc. In general application of oil and gas, the

soft seated ball valve is used. This type of seat will provide an excellent sealing capability with a fair life time in clean service application. While the metal seated ball valve is used when the soft seated ball valve can’t handle anymore the process condition.

Some valve manufacturers use a pure soft material as their soft seat material and there are also manufactures that use a metal oring (metal seat ring) and soft material as its seat insert for size 2 inch and above. This type of seat even though it use a metal seat ring but it is categorized as soft seated ball valve due to it use a

soft material as final part that in contact with the ball.

 

Sourced by ekomeri.com

The post Soft Seated or Metal Seated Ball Valves? appeared first on KST Plant.