The components used in a piping system to connect the various sections of the pipe in order to change the direction of flow, are called fittings. Fittings are made from a number of materials including steel, bronze, cast iron, plastic and glass.
Standards have been established to ensure that fittings are made from proper materials and are able to handle the designed pressures. Some of the important functions of these fittings are:
- Changing the direction of flow
- Providing branch connections
- Changing the size of lines
- Closing lines
- Connecting lines.
Fittings for Changing The Direction of Flow
To change the direction of flow, the pipe fittings that are normally used are referred to as elbows. Elbows generally come in all angles but those that are commonly used are the 45° and 90° ones.
Fittings for Changing The Size of The Pipelines
The function of the reducer is to reduce the line to a smaller pipe size. One reason for doing so is to increase the pressure in the system.
Pipe Joints
Pipe joints can be of the screwed, flanged or welded type. Each of these joints which are widely used, have their own advantages and disadvantages.
Screwed fittings are joined to the pipe by means of threads. The main advantage of the threaded joints is that the pipe length can be easily tailored at a later stage. As a threaded joint has metal-to-metal contact between the threads of two mating parts of the pipe, the risk of leakage is high. Hence sealing of the threaded joint becomes very important. The traditional method of providing a seal between the mating threads is to coat the threads with a paste dope. In recent years, the invention of Teflon sealing tapes has made for a more effective solution. The Teflon (being a registered trademark of Du Pont De Neumors and Company) tape can be simply wound over the threads for sealing.
Flanged fittings are either forged or made as cast pipe fittings. A flange is a rim or ring at the end of the fitting, which mates with another section of the pipe. Pipe sections can also be made with flanged ends. Flanges are joined either by being bolted together or by being welded together. The flanged faces again have metal-to-metal contact and proper sealing needs to be provided between the two mating surfaces to avoid leakages. A gasket is usually inserted between the mating surfaces of two flanges, which are bolted together. Normally, compressed asbestos gaskets can be used under conditions of normal pressure and temperature. However, when the system operates under higher pressure and temperature conditions, higher-grade gaskets are used.
Other pipe fittings used in flanged connections include expansion joints and vibration dampeners. Expansion joints have three functions:
- They compensate for slight changes in the length of the pipes, by allowing the joined sections of rigid pipes to expand or contract with changes in temperature.
- They allow pipe motion either to the side or along the length of the pipe, as the pipe shifts after installation.
- They help dampen vibration to some extent and reduce the noise carried along the pipe and originating from distant pumps.
It has a leak proof tube that extends through the bore and forms the outside surface of the flanges. Natural or synthetic rubber compounds are used for this purpose, depending on the type of application. Other types of expansion joints include metal bellows (corrugated type), spiral wound types and slip joint types.
Vibration dampeners are designed specifically to absorb vibration because vibrations reduce the life of the pipes as well as the operating equipment. They also eliminate line noises carried by the pipes.
Wellgrow Industries Corp. is the professional cast pipe fittings and other stainless fittings manufacturer in the industry. If you are interested in learning more information about pipe fittings, try to visit the website of Wellgrow to see what products they can offer you!
Article Source: http://machineryequipmentonline.com/hydraulics-and-pneumatics/hydraulic-accessoriesfluid-conductors-hydraulic-pipes-and-hoses/