Metal Bellows Expansion Joints

Weld end metal bellow expansion joints have sections of pipe attached to each end of the bellows intended for welded installation.  This style’s design has a flangeless installation and greater sealing properties.

Fixed flange bellows are constructed with raised face or plate flanges welded to the end of the bellows.  Fixed flange ends require knowledge of bolt hole alignment for each end it will be installed.  This style is best suited for Class-D applications.

Raised face flange bellows are provided with Class 150 drilling or Class 300 drilling carbon steel raised face slip-on flanges.  This style has a concentrated sealing area and provides an increased pressure capacity.

Floating flange (Van Stone) metal bellows are provided with raised face or plate flanges with your required drilling pattern and are fully rotatable on each end of the joint.  The necks of the bellows are flared to retain the flanges.  Floating flange configurations allow for carbon steel flanges with all wetted components stainless steel or other alloy.  Floating flanges also allow for bolt hole alignment in the field.

Metal expansion joints are often constructed with a combination of the flange types.  Regardless of your needs, our craftsman can assemble the joint to your specifications.   Combination of flange types allows for multiple installation types and increased compatibility.

Universal tied bellows are capable of absorbing larger lateral movements than standard single joints and offer increased flexible surface.  Available with optional liners or covers.

Externally pressurized bellows feature an anti-squirm design and can handle large axial movements.  This is an exceptional product for absorbing large amounts of axial movement in long, straight pipe runs. One of the safest and most reliable joints, the unique design features make this an appealing option for steam and condensate applications.

A hinged expansion joint is designed to permit angular rotation in only one plane by using a pair of pins through hinge plates attached to each end of the expansion joint. Hinge hardware and pins are designed to restrain pressure thrust of the bellows and any extraneous forces where applicable. Hinged expansion joints must be used in sets of 2 or 3 to function properly and they do not need to be co-linear.

A gimbal expansion joint is designed to permit angular rotation in any plane by using two pairs of hinges attached to a common floating gimbal ring/box. Gimbal ring/box, hinge arms and pins are designed to restrain pressure thrust of the bellows and any extraneous forces where applicable. Typical gimbal systems consist of 2 gimbal expansion joints or 2 gimbal and 1 hinge expansion joints. Just as hinged expansion joints offer great advantages in single plane applications, gimbal expansion joints are designed to offer similar advantages in multi-plane systems. Since gimbal expansion joints are not restricted to single plane systems, they have greater flexibility of usage.

Flexible Metal Pump Connectors are designed with a flexible core of corrugated tin bronze or type 321 stainless steel tubing under the braid.  Flat-face flanges are standard; however, other types are available.  A wire braid is used over the flexible core on most designs to provide strength for the rated operating pressure.