Although no one corrugation profile or manufacturing method is superior for all design conditions, each has its own performance characteristics that, along with costs, must be considered. MDC’s low pressure FSF and FSW styles for pressures of up to 50 psig are widely used in such applications as steam, condensate, water and process lines, turbine condenser connections, fuel supply lines and bulkhead seals.

These non-ring controlled (or free flexing) expansion joints are suitable for lower system pressures. Relatively thick bellows walls are ideal for resistance from pitting corrosion (with proper bellows material provided) and their high corrugation profile is capable of absorbing large axial movements. Vibration and high frequency movements are better handled by low/mid corr and multi-ply bellows.

MDC’s high pressure CSF and CSW styles for pressures of 150 and 300 psig are recommended for steam (with internal liners) and other high pressure, high temperature applications. The equalizing rings reinforce the bellows and spread the movement and stresses equally over all corrugations. This ensures maximum cycle life, as no one corrugation will ever over-compress.

Greater movement (up to 7-1/2”) can be handled with this type of joint, thereby reducing the number of joints needed. Dual joints in this design can provide up to 15 inches of axial Dual joints are always supplied with an intermediate anchor base. Anchor base is optional for a single joint.