How do I choose the expansion bellows?
For the selection of the most suitable PosiFlex expansion joint, the following basic criteria must be determined:
- Size – joint nominal bore size, required face-to-face length and mating flange size/specification.
- Pressure – operating, design, surge and test pressure of the system.
How wide should an expansion joint be?
Joints should be at least 1/2-inch to 3/4-inch wide. Expansion joints should extend beyond the full depth of the concrete slab. Use a screwdriver to confirm that each joint at least 4-inches deep.
What is the purpose of expansion bellows?
Expansion joints (bellows) Expansion joints are installed in a piping system to absorb vibration and shock. They also have advantages such as reducing the noise and compensate caused by misalignment. Special expansion joints can also be designed for thermal expansion in hot applications.
What are the types of expansion joints?
Other types of expansion joints can include: fabric expansion joint, metal expansion joint (Pressure balanced expansion joints are a type of Metal expansion joints), toroidal expansion joint, gimbal expansion joint, universal expansion joint, in-line expansion joint, refractory lined expansion joint, hinged expansion …
Should expansion joints be filled?
Just remember that expansion joints should always be sealed and filled with a flexible joint sealer and never epoxied or coated over. Contraction joints can be filled in the same manner after a coating or sealer is applied if you desire.
Do you need to put expansion joints in concrete?
Expansion joints are virtually never needed with interior slabs, because the concrete doesn’t expand that much—it never gets that hot. Expansion joints in concrete pavement are also seldom needed, since the contraction joints open enough (from drying shrinkage) to account for temperature expansion.
Why expansion bellows are used in heat exchanger?
Expansion bellows are applicable to fixed tube sheet heat exchanger which help in reducing the longitudinal stresses or tube to tubesheet joint loads by allowing the axial displacement between shell and tubes.
What is a bellows type?
There are three main types of metal bellows: formed, welded and electroformed. Formed bellows are produced by reworking tubes, normally produced by deep drawing, with a variety of processes, including cold forming (rolling), and hydroforming. They are also called convoluted bellows or sylphons.
How do you build an expansion joint?
5 Steps to Expansion Joint Specification Perfection
- Step 1: Understand the movement requirements.
- Step 2: Size the joints properly.
- Step 3: Consider joint locations and application requirements.
- Step 4: Identify adjacent surface finishes.
- Step 5: Installation Method.
How deep should expansion joints be cut in concrete?
A good rule of thumb is to cut the joints one-quarter to one-third the slab thickness. For a 6-inch-thick slab, that means cutting 1 1/2 to 2 inches deep. Ensure that the saw cut depth meets the structural engineering specifications.