Metal Expansion

Metal Expansion Joint

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The selection of the optimum expansion joint depends on a technical as well as an economical aspect. With many years of experience in design, production and marketing of expansion joints, we are competitive and specialized on the know-how on the solution for demand required in a technical and economical view.

The physical capacity of bellows to absorb movement is determined by the number of corrugations, pitch (P), height (H), pipe diameter (D), spacing (L), thickness of material (t), and number of layers (n). The basic constituent element of expansion joint, bellows can be specified, considering on movement, pressure, temperature, service life and corrosion rate required.

The basic advantages using expansion joints are as follows:
  • To absorb movement
  • To relieve system strain due to thermal change, load stress, pumping surges etc.
  • To reduce mechanical noise and vibration
  • To compensate for misalignment
  • To eliminate electrolysis between dissimilar metals
There are three basic movements that can be absorbed by an expansion joint:
  • Axial movement is the change in its longitudinal axis.
  • Angular movement is the rotational displacement
  • Lateral movement is the displacement of perpendicular to its longitudinal axis
Expansion joints are designed, manufactured and tested in accordance with following Code and Std.
  • Expansion Joint Manufacturer Association, Inc. 10th ED.
  • ASME B31.3 App. X
  • ASME Sec. Ⅷ Div.1, App.26, as required
  • EN 14917 Metal Bellows Expansion Joints for Pressure Applications
Engineering products, expansion joint & flexible products, which can absorb thermal and mechanical movements in pipe-work and duct systems, provide solution to engineering problems.
Applications are as diverse as there are industries. There are applications in
  • Process Engineering
  • Nuclear
  • Power Generation Manufacturing
  • Heating Ventilating and A/C
  • Petrochemical
  • Aerospace
  • Construction
  • Automotive
  • Cryogenic
  • Combustion Engine
  • Metallurgy
Forming method
The bellows is the basic element of expansion joint, which can be made by expanding, mechanical and hydraulic forming as the requirement in MEGAFLEXON facility.
Normally, metal expansion joint are produced by hydraulic mandrel punch forming. According to the specification, our bellows are designed to be expanded by using a specially designed.
In this method, MEGAFLEXON can produce up to 1,500 mm in nominal diameter.
All bellows are formed in their cold state without heat treatment but it can be heat treated, in case that specially required.

Our standard material for the circular type bellows is austenitic steel, that is, SS 304 and 316. In addition, other special nickel based alloy material, like as Inconel, Incoloy, Monel and Hasteloy can be applied on the servicing of aggressive fluid.

Basically, austenitic steel is resistant to both high temperature and aggressive media. It has a good mechanical property as well when it comes to the effect of continuous motion in axial, lateral and angular direction. MEGAFLEXON bellows have been improved to achieve an optimized relationship between the various parameters, so that the bellows can withstand the greatest possible load without fail on normal operating condition.