Expansion Fittings accommodate for conduit thermal expansion and contraction to compensate for length changes due to temperature variations in exposed conduit runs.
Expansion fittings are used in aboveground installations where temperature changes are anticipated to exceed 25°F (14°C). Rigid PVC conduit has a coefficient of expansion of 3.38 x 10–5 in./in./°F. A 10 foot length will change in length about 3/8” with a change in temperature of 100°F.
Expansion couplings are used mainly to connect two pieces of pipe together. Have questions regarding our products or need a quote?
A expansion joint, or movement joint, is an assembly designed to hold parts together while safely absorbing temperature-induced expansion and contraction of building materials. They are commonly found between sections of buildings, bridges, sidewalks, railway tracks, piping systems, ships, and other structures.
Raceways shall be provided with expansion fittings where necessary to compensate for thermal expansion and contraction.
Expansion joints are designed to safely absorb the movement in pipework systems due to heat-induced expansion and contraction of pipework. When a pipeline is subject to a change in temperature it will expand or contract in direct proportion to that change.
A raceway, sometimes referred to as a raceway system, is an enclosed conduit that forms a physical pathway for electrical wiring. Raceways protect wires and cables from heat, humidity, corrosion, water intrusion and general physical threats.
Concrete expansion joints are particularly important where there have been consecutive concrete pours and are also useful when laying concrete within an area bordered by walls or buildings or if objects such as manhole covers need to be incorporated.
Explanation: As per IS- 456:2000, in the case of buildings, structures exceeding 45 m in length are designed with one or more expansion joints. As per IS 3414 which is a specific code for joints, it is mentioned as 30 m. It is clear from the above table that the maximum spacing for the expansion joint is 140 m.
Expansion loops provide sufficient flexibility to prevent thermal expansion and contraction from causing excessive stresses in the piping system. Expansion loops often are required in high-temperature gas well flow lines and gas and water injection lines.
Expansion joints in walls at 30 m maximum intervals. (If the walls are panel walls between columns at not more than 9 m centres no joints are necessary.) Control joints over centre of openings may be given at half the spacing of expansion joints.
There are other terms in use for Expansion Joints such as Expansion Bellows, Flexible Joints and Compensators. A typical Expansion Joint is comprised of one or more metal bellows (most commonly stainless steel) or from materials such as rubber, fabric or plastic such as PTFE.
They are used to absorb thermal expansion, accommodate building settling, and prevent damage during ground movement. By allowing pipes to move and flex, these couplings ensure that your plumbing system remains reliable and leak-free.
SharkBite PEX-a expansion fittings are best used to accommodate expansions and contractions in aboveground pipe installations when temperature levels exceed normal levels. Its flexibility and elastic memory makes PEX-a tubing ideal for this kind of installation.
Having the right amount of expansion joints between concrete slabs is essential, but large openings exposed to the elements can cause many different problems over the lifetime of the concrete. For this reason, it's important to fill or seal your expansion joints.
352.44 Expansion Fittings and Earth Movement. Expansion fittings must be installed above grade when direct buried PVC conduit emerges from the ground and compensation is needed for earth settling or movement, including frost heave.
Cold joints have a negative effect on the structure; they can reduce the load-bearing capacity by creating weak points in areas subject to shear or tensile forces. They are also possible entry points for water or other contaminants, which could cause a concrete crack or deterioration.
Expansion joints allow thermal contraction and dilatation without causing stress inside the structure. A dilatation joint is designed to safely absorb the expansion and contraction of various construction materials, absorb vibrations, and allow the building to properly accommodate earth movements caused by earthquakes.
When spacing out joint cuts, the general rule of thumb is that each joint should be around 2-3 times the thickness of the slab, but in feet. So, for example, for a 4-inch slab, joints should be about 8 to 12 feet apart.
If expansion joints are not present in a large building or structure, that building is subject to cracking or damage over time. An expansion joint cover is designed to close those gaps while functioning to accommodate the expected movement.
However, if they must be put in a vertical application, the open end should be securely fastened in the down position. The expansion fitting must be installed close to the top of the run with the barrel pointing down, so that rain water does not enter into the opening.
Raceways are often used for surface mounting and provide easier access to cables, while conduits are often buried or hidden within walls for added protection.
MC cable can be used outdoors, while BX cannot. Additionally, MC cables do not have a limit on the number of conductors they can contain, whereas BX cables can hold up to four insulated conductors.
The advantages of raceways are that they can be easily built in series, with the water flowing from one to the other and they are easy to empty of fish by using a simple crowding screen.