Expansion joints

Thick Wall expansion joints are frequently used in heat exchangers, furnace and blast furnace pipe work.

These may be a cost-effective option for large-diameter piping systems which operate at low pressure. Metals can be selected to satisfy different temperature conditions. The distribution of axial, angular, and lateral forces will be different when thick-wall pipe expansion joints are used. We can provide your design engineers with the potential forces and movements for proper design of the structural members supporting the system. These joints have a long life which justifies the initial investment.

Thick-wall expansion joints are used primarily in heat exchangers and large diameter piping systems where thin-wall expansion joints would not be sufficient. The bellows are typically fabricated from A516 Grade 70 material, with the thickness ranging from 3/16″ to 1″. Other materials are available to meet different temperature requirements.

Thick Wall Expansion Joints are normally supplied without any end connections due to the fact that it is easier to weld the end fittings to them by a relatively less skilled welders. The heavy wall bellows are less susceptible to damage during installation and system start-up however these bellows possess high spring forces as a result of high convolution profile. The thickness of these thick wall bellows elements vary from 1 mm to 3 mm depending up on size and the height of convolution varies from 50 mm to 100 mm.

Thick Wall Expansion Joint (Bellows), has a very diverse methodology, which is explained in one of the articles below. The following calculations are supported:

• Cylinder calculations
• Differential axial thermal expansion
• Axial rigidity
• Radii requirements
• Cylinder calculations
• Cycle life
• Minimum thickness based on material and service