Tag: faq

The limiting factors correspond to the limiting factors of the bellows design in accordance with the specifications of each expansion joint.

The three basic movements within an expansion joint are axial, lateral, or angular rotation. All three of these movements do not generally occur at the same time.

The anchors are located at the lower floor and upper floor of chilled water risers and guides should be located on alternating floors. The expansion joints should then be located near the main anchors.

An intermediate anchor is a stop in the piping system that divides the movement between expansion joints.

Convolutions are the smallest flexible unit of a bellows. The total movement capacity of a bellows is proportional to the number of convolutions.

We generally use universal primer for expansion joints, unless the customer specifies a specific paint.

Yes, the limit rod will prevent damage of expansion joint in case of anchor failure in the line. Also, the rod will prevent damage to the expansion joint by distributing the movements evenly between the bellows

We do not put slots on our expansion joints, but we leave a minimum gap between the nuts and the lug depending on the lateral movement.

US Bellows, Inc. designs bellows for condition requirements.

The branch of a balanced Tee is in the flow path.

It depends upon the diameter of the expansion joints. Generally for the smaller expansion joints, seamless is available.

It depends upon the pipeline design. For example, if there is a long run of pipe on both sides, then we need guides on both sides. If the expansion joint is located close to an anchor, then guides are only required on the long side.

You should never punch a hole into an expansion joint.

Yes, this expansion joint is obviously more expensive than the similar types, however they may result in a lower overall system cost when the elimination of main anchoring is considered.

Yes, it is safe to use 304 Stainless Steel, but high alloy materials such as Inconel® and Monel® are better options for a salt water atmosphere.

Expansion joints should be pre-compressed for low-temperature/cryogenic applications because when the pipe gets cold it will contract.

Yes, if they are testing just the expansion joint or if they are testing when installed, they have to make sure that the pipe line is anchored or have limit rods added to the expansion joint to absorb the pressure thrust.

We have standard lengths that are listed in our catalog, however, we can make our expansion joints longer or shorter than what our catalog states. We also can furnish piping assemblies with pipe and fitting as may be required.

Buckling typically occurs while the pipe in compression mode and is not normally related to the tension mode of the pipe.

The expansion joint cycle is a design condition – stated by the customer or a number we provide according to the design of the expansion joint which refers to the expansion joint moving from the neutral position to compression and back to neutral.