To understand what valves you need, you need to know what a valve is and how it functions. Valves control flow and pressure within a system. These devices are mechanical and come in different shapes and forms depending on their specific use. Read on for everything you need to know.
How valves work
Think of valves as operating like a switch, which turns a pipe either on or off to increase or decrease the amount of fluid or gasses traveling through the channel. One example is your bathroom faucet. When the tap moves to open or close flow, the valve releases water pressurized from the pipes. People can open the valve partially or completely to release different levels of pressure, and thus obtain the necessary flow of water.
Machines that handle liquids or gasses are practically guaranteed to have some sort of valve mechanism. These components are essential to everyday items, including washing machines, cars, and kitchen faucets, among many others.
Types of valves
There are several types of valves including ball, butterfly, plug, gate, globe, needle, poppet, and spool valves, among others. A ball valve uses a sphere which sits inside of the pipe to block the flow of fluid or gas. When the circuit is opened, the ball swivels, permitting the flow. A butterfly design uses a disk that sits in the middle and moves sideways to open the circuit. A cock plug uses a cone-shaped plug that moves aside with a turning wheel. Gate valves, instead, lower a metal gate to close and raises said gate to open. A globe valve is most commonly used in water taps, and can regulate the amount of flow, making it a perfect mechanism for water pressure.
Valves function by allowing or stopping, reducing or increasing, directing or regulating pressure from a liquid or gas flow. Each design serves a particular purpose, and therefore, the use of the valve determines the appropriateness of the style. Since this item can be expensive, it is important to understand the function that the valve performs. It is best to consult experts who can recommend specific designs based on your project needs. Furthermore, interested parties can save money by looking for remanufactured valves, such as Fisher control valves provided by Automation Service.
Parts of the valve
All valves have some common parts, including the body, trim, bonnet, actuator, and packing. The body, also known as the shell, is the main part of the mechanism and holds all the components. It is the first pressure boundary and resists fluid pressure. The bonnet is the second most important part and covers the body. The valve trim is an interchangeable part that can be replaced and comes in contact with the flow. This part includes the seats, discs, glands, and other components. The trim allows for basic movements and can be constructed using different types of materials. These materials must take into account the temperature, chemical type, velocity, and viscosity of the flow.
The movement for the disc, plug, or valve mechanism previously introduced is provided by the valve stem. This is connected to the actuator or lever on one of the ends. The packing is what provides a seal between the stem and the bonnet. This part contains the gland follower, gland, and stuffing box.
A valve gland, also known as a gland brushing, is in charge of retaining or compressing the stem packing. This process occurs in the stuffing box of the valve. The packaging, including the gland, is important because it is subject to normal wear and tear. Furthermore, to avoid a loss in pressure or fluid, this part must be in good condition.