Expansion joints are devices that are used to allow the mitigation and expansion induced by the heat that takes place in various states of the climate. These expansion joints offer an innovative and reliable solution for different types of applications such as power generation, power plants, shipbuilding, district heating, wind power, cement plant and many other industries. The joints offer a full range of metal expansion joints ranging from low pressure exhaust bellows to a complex engineering solution for fluid catalytic cracking units.
What is Bellow Coupling?
Usually, flexible bellows coupling manufacturers make couplings by a hydroformed stainless-steel tube to create deep corrugations which make it flexible along axial, angular and parallel axis misalignments. The bellows absorbs any slight mismatch between the two component mounting surfaces.
One form of flexible bellows coupling with very low and almost zero play is the bellows coupling. The main advantages of bellows couplings consist of misalignment compensation and accurate transmission of speed, angular positioning and torque. Bellows couplings are best known for their superior torsional rigidity, overall flexibility in the treatment of axial, angular and identical axis misalignment.
Types of Bellow Couplings
Clamp or pressure-resistant couplings comprise of two parts and are built around the shafts into a sleeve. They provide much more flexibility than sleeved models that can be used on fixed shafts. They usually are large enough to guide screws through the coupling and also into the second half to ensure a secure fit. Rigid flange couplings are designed for heavy loads or industrial installations. They consist of short sleeves, which are surrounded by a vertical flange. A coupling is arranged on each shaft so that the two flanges face each other. A set of screws or bolts can then be installed in the flanges to hold them together. Due to their size and durability, flange units can be used to align shafts before they are joined together.
However there are two main types of couplings which are rigid couplings, and flexible couplings.
The rigid couplings are of the following types.
Coupling sleeve: one of the simple types of rigid coupling is a sleeve coupling consisting of a cylindrical sleeve keyed to the axes to be connected. The sleeve transmits torque from one shaft to the other. Normally sunken wrenches are used and to transmit the torque safely it is important to design the sleeve and the wrench correctly. The key design is usually based on shearing and rolling efforts.
Coupling of sleeve with conical pins: the transmission of torque from one shaft to another can also be done with pins.
Clamp Coupling: A typical clamp coupling consists essentially of two half-cylinders that are placed on the ends of the shafts for coupling and held together by a through bolt.
Ring compression type couplings: the coupling consists of two cones that are placed on the shafts for coupling and a sleeve that fits over the cones. Three bolts are used to draw the cones towards each other and thus to fit them firmly between the axes and the outer sleeve.
Flange coupling: it is a rigid coupling very used and consists of two flanges keyed to the axes and screwed. The main design features are essentially (I) bolt design, (ii) bucket design, and (iii) overall design and dimensions.
The flexible couplings are of the following types
Elastomeric couplings: In general, these couplings have the flexibility to stretch or compress an elastic material (rubber, plastic, etc.). Some landslides or rollers can take place, but it is usually minimal.
Mechanically flexible couplings: In general, these couplings get their flexibility from the loose parts and / or from the rolling or sliding of the complementary parts. Therefore, they generally require lubrication unless a moving part is made of a material that provides its own lubrication needs (for example, a nylon gear coupling). Also included in this category are couplings that use a combination of loose and / or rolling or sliding parts with some bending of the material.
Metallic Diaphragm Couplings: In general, the flexibility of these couplings is achieved by bending thin metal disks or diaphragms.
Different couplings: These couplings get their flexibility through a combination of the mechanisms described above or through a unique mechanism such as spring clutches.
Stainless Steel Bellows Couplings
Stainless Steel Bellows Couplings are torsionally rigid couplings, also bellows couplings, metal bellows couplings, miniature couplings, servo couplings, torsionally stiff couplings, bellows couplings, etc. They transmit the rotation without play and at precise angles from one end of the shaft to the other. Axis errors due to production and assembly inaccuracies as well as thermal expansion and other deformations are compensated by the lateral, angular and axially flexible metal bellows. There is no high inadmissible support load, which could otherwise be caused by rigid couplings. The different types of couplings differ in different sizes and in the type of shaft-hub connection, more in the material. The keyways and the like are usually not necessary.
The Pliant Bellows features the traditional stainless steel bellows coupling, which can be used in a variety of applications. Its core properties are backlash-free torque transmission, high torsional rigidity and excellent compensation of angular, axial and radial misalignments. Operational safety and ease of installation are two more factors in favor of Pliant Bellow Flexible Bellows Coupling Manufacturers in India.