Metal Bellows

BELLOWS DESIGN :

The bellows is the flexible element of the expansion joint. It must be strong enough circumferential to withstand the pressure and flexible enough longitudinally to accept the deflections for which it was designed, and as repetitively as necessary with a minimum resistance. This strength with flexibility is a unique design problem that is not often found in other components in industrial equipment.

Metal Bellows Design

Most engineered structures are designed to inhibit deflection when acted upon by outside forces. Since the bellows must accept deflections repetitively, and deflections result in stresses, these stresses must be kept as low as possible so that the repeated deflections will not result in premature fatigue failures. Reducing bending stress resulting from a given deflection is easily achieved by simply reducing the thickness of the bending member, which in the case of the bellows, is the convolution. However, in order to withstand the pressure, the convolution, which is also a pressure vessel, must have a thickness great enough that the pressure induced membrane stresses are equal to or less than the allowable stress levels of the materials at the design temperatures. This conflicting need for thickness for pressure and thinness for flexibility is the unique design problem faced by the expansion joint designer.

Howls are not springs, in that the vast majority of their redirection produce bowing anxieties in overabundance of the materials' yield quality. Seeing how different materials perform and their capacities in this "plastic" distortion locale requires years of experience and plan conditions based upon this exact comprehension. 

That howls routinely work "plastic-ally" ought not be a reason for worry, subsequent to the majority of the materials from which cries are made offer comparable exceptionally malleable qualities. Specifically, the perseverance furthest reaches of these materials, which can be approximately portrayed as the anxiety at which disappointment will happen at ten million cycles of rehashed focusing, is about the same as their yield stress, or the time when perpetual distortion will happen. A cries which is required to withstand 3000 cycles of a given redirection and weight, and which at last falls flat after 10,000 cycles, has unquestionably exhibited more than worthy execution. Nonetheless, it has encountered, amid every last cycle, twisting burdens far in overabundance of as far as possible and along these lines the yield stress, and once avoided, would not have returned all alone to their unique un-deflected length or shape, as a spring is required to do. At the end of the day, they would have "taken a set."

Products  :

1) Bellows Coupling.

2) Valve Bellows.

3) Pressure switches Bellows.

4) Axial Expansion Joints.

5) Lateral Expansion Joints.

6) Hinged Expansion Joints.

7) Gimbal Expansion Joints.

8) Inline Pressure Balanced Expansion Joints.

9) Elbow Pressure Balanced Expansion Joints.

VALVE BELLOWS

Bellow sealed valves are a new type of Industrial Process valves. These valves are popular due to the leakage free performance hence, called “Zero Leak Valves” or “Emission Free Valves”.

With the application of Bellow seals the gland packing is supplemented by a metallic Bellow cartridge. One end of the Bellow is connected to the valve bonnet and the other end to the stem. The bellow movement is in one plane as the stroke in the valve takes place. With no rotational movements involved the fluid gets sealed to a very high degree. The fluid flows through the bottom part of the valve as per the stem movement takes place. Due to the bellow covering the stem the seal does not contact the stem at all. As the stem is the moving part in the valve it is the source of leakage due to the wear and tear of gland packing. Due to this shielding of the stem by the bellow the valve operated in a leak free zone.

The life cycle of the metal Bellow is largely dependent on the process of bellow manufacturing. At Pliant Bellows we manufacture them by hydro forming process. The properties achieved by the hydro forming process are far superior as compared to other process like, diaphragm welded bellows or mechanically drawn bellows. It is extremely important that the bellows have the mechanical and metallurgical properties for long cycle life of an bellow to avoid

Valve Bellows Manufacture in India | Pune, Valve Bellows  in India | Pune valve bellows  is a device, which arranges and controls the surge of fluid (slurries, fluidized solids, liquids, and gasses) by closing, opening or to some degree blocking various ways. Really, the Valves Bellows are known as a pipe fitting yet consistently discussed in discrete class.

The fundamental vision of Micro finish is to give wonderful administrations to the clients, give top quality valves, lastly meet the exceptional time point of confinement of the client.

Bellows Couplings – Flexibility and Accuracy for Motion Control Applications

Bellows Couplings – Flexibility and Accuracy                for Motion Control Applications

Reliable, flexible and permanently backlash-free shaft coupling

SO IN SHORT ONE SHOULD USE THESE BELLOWS IN FOLLOWING CIRCUMSTANCES:

• Excellent misalignment capability (compensation of shaft misalignment)
• Minimum mass moment of inertia
• High torsional rigidity
• High availability due to flexible modular construction
• Simple and fast attachment via one screw
• Nominal torque: 16 up to 700 Nm

The torque on the clamping connection, which is transmitted via frictional locking, is dependent on the hub bore (shaft diameter). For permitted values and detailed information on size selection, please see the Product Catalog. Metal bellows couplings guarantee a zero backlash torque transmission with extremely high torsional stiffness and a low moment of inertia. Different types of bellows, conical bushings and clamping hubs are available for different applications.

BELLOWS COUPLINGS

CHARACTERISTICS OF METAL BELLOWS COUPLINGS:

1. Torque range up to 700 Nm
2. high torsional stiffness
3. temperatures of up to 350°C
4. high speed
5. optional: stainless steel

OUR PRODUCTS

Elbow Pressure Balanced Expansion Joint

An Elbow Pressure Balanced Expansion Joint is designed to absorb externally imposed axial movement without imposing pressure loading on the system. This is accomplished by using two bellows both at line pressure tied together and acting in opposite directions. It is used where pressure loading on piping or equipment is not acceptable.

UNIVERSAL EXPANSION JOINT

Universal expansion joints is made up of 2 elements of bellows joined together by a common spool piece so it is also called as Double Bellows Expansion Joint or Universal Bellows. A Universal Expansion Joint is generally used where more lateral movement is to be absorbed which is beyond the capacity of a single Axial Expansion Joint and when there is a limitation on the amount of lateral forces allowed by the connecting pipe system Universal expansion joints can take deflection in lateral, axial or angular movements.

Universal expansion joints




The universal expansion joint consists of two bellows separated by a pipe section or spool. The primary purpose of this arrangement is to have a unit which will accept large amounts of lateral deflection.

The amount of lateral deflection they can accept is a function of the amount of angulation. These joints have no restrains to resist pressure thrust like the axial. For a given bellows element, the amount of lateral deflection capability be increased or decreased by simply changing the length of the center spool.

A universal expansion joint is composed of two bellows connected by a common pipe or center spool. This type of assembly allows any combination of the three basic movements: axial, lateral and angular. A universal expansion joint is generally used In cases with more lateral movement than can be absorbed by a single axial expansion joint, or when there is a limitation on the amount ot lateral forces allowed by the connecting pipe system. The lateral movement capability of e universal expansion joint depends on the centro spool length. When using a universal expansion joint, anchors must be sufficiently designed to withstand the full thrust forces .