Ball Valves

Ball Valves As the name suggests, they are valves that use a Sphere to manage flow. These valves work by allowing the opening to be opened, blocked or partially opened to control gas/liquid flow. Ball valves are the best alternative for gases as they are ready to provide higher protection. They are versatile as they support pressures up to 700 bar and temperatures up to 550°C. They are easy to inspect and repair as they have a simple construction.

It is the design that allows only a 90-degree turn that is necessary for the movement of ball valves. These valves are a remarkable industrial alternative, attributable to their reliable and airtight protection when in the closed position.

Species

1- Floating Ball Valves

In a floating ball valve, the ball is held in position by compressing two elastomeric seats against the ball. The ball can float freely inside the valve body.

2- Trunnion Ball Valves

Trunnion mounted valves are a solution to the problem of excessive torque required by a Floating type valve in high pressure service. The body has a short set of shafts as an extension known as a Trunnion.

Ball Valve Types According to Body Structure

Top Entry Ball Valve

In the Top Entry Ball Valve, removing the cover cap of top entry valves allows access to the valve internals for assembly, disassembly, repair or maintenance without removing the valve from the pipeline.

Split Ball Valve

In this design, a valve body is divided into two or three body parts. A ball, seat rings, stem and other internal parts are placed inside the larger body part and held together with the smaller parts by bolting. The split body has two parts floating for the valve.

Side Entry Ball Valve

Side entry ball valves are valves that mount their ball from the side. They are usually mounted in a two-piece or three-piece body.

Difference Between Floating and Trunnion Ball Valves

In Floating Ball Valve design, as the name suggests, the Sphere does not have a fixed position and can change its position with line pressure. The spherical stem connection allows a certain amount of lateral movement during Quarter Turn. The Sphere seals by pressurizing the bearing surfaces with the force exerted by the flow through the line. With its simple design and reliable sealing performance, it is widely used especially at low pressures and diameters. However, as the line diameter increases and the pressure increases, the force exerted by the sphere on the seats goes beyond the strength limits of the gasket, which is usually made of PTFE based materials. In Trunnion Ball Valve design, the sphere – stem is fixed, Trunnion Ball valves can be used safely in high diameters and pressure classes. Floating Ball Valves cannot perform. Trunnion Ball Valves have lower torque requirements than Floating Ball Valves of the same diameter and pressure class. In this way, they provide economic advantages with much lower operating costs, especially where automation is required.

Advantages

They have a compact and low-maintenance style that does not require lubrication. they are cost-effective among all valves

• They provide leak-proof service.

They open and close quickly. Ball valves have versatile styling flexibility.

Disadvantages

Ball valves are not suitable for permanent choking. In residual fluids, particles in the fluid touch the surfaces and remain with them. this can cause discharge, wear and alternative problems.

Applications:

Ball Valves are valves used for flow and pressure management and shutoff for corrosive liquids, slurries, conventional liquids and gases. They are used in the oil and gas industry, but together they have uses in many manufacturing sectors, chemical storage and even residential applications.

• It can be used in different types of fluid services as an on-off stop valve providing bubble-tight shut-off.
• It can be used in air, gas and steam services and hydrocarbon services.
• Metal seated valves can be used in high pressure and temperature applications.
• widely used with tool pipes to connect tools.