How do you compensate for thermal expansion?

Another example of a method to compensation for thermal expansion is expansion joints. Bridges are built with metal expansion joints, which contain gaps between bridge sections that allow for expansion and contraction without causing faults in the overall structure of the bridge.

How can we prevent thermal expansion?

One approach is to restrict the stress to the piping and so avoid the need for beefed-up equipment flanges, etc. Special pipe supports can prevent stress from being transferred to equipment. Materials with a lower coefficient of thermal expansion (α) grow less when heated.

How do we stop expansion damaging a bridge or railway line?

One way to counteract this problem is by using expansion joints. Expansion joints fill gaps within the bridge and act as a flexible, variable filler that help the bridge adapt to temperature changes without distorting.

What would happen to a railway track that does not have expansion gaps?

The gaps left between successive rails on a railway track, the reason is that the rails expand in summer. The gap is provided to allow for this expansion. If no gap is left, the expansion in summer will cause the rails to bend sideways. That will result in train accidents.

What is thermal contraction?

Thermal contraction is a decrease in a material’s volume when its temperature decreases. As the temperature decreases, the average kinetic energy of the particles decreases and they slow down and get closer together thereby decreasing the volume of the material.

What are some examples of thermal expansion and contraction?

So provision is made during contraction for expansion and contraction with temperature. For example, railway tracks buckled on a hot summer day due to expansion if gaps are not left between sections. Bridges made of steel girders also expand during the day and contract during the night.

What is a thermal expansion control?

A thermal expansion control valve is essentially a pressure relief valve installed at a water heater to prevent forming excessive pressures in the closed loop of water supply piping and water pressure tank when water is heated at the water heater.

How do you test for thermal expansion?

Linear thermal expansion is ΔL = αLΔT, where ΔL is the change in length L, ΔT is the change in temperature, and α is the coefficient of linear expansion, which varies slightly with temperature. The change in area due to thermal expansion is ΔA = 2αAΔT, where ΔA is the change in area.

How do engineers deal with thermal expansion?

Intentional cracks in the sidewalk are a perfect example of how engineers deal with thermal expansion. By filling these gaps with a flexible material, the engineers create what’s known as a “expansion joint,” something that’s meant to help a structure keep its form even with shifting temperatures.

How is thermal expansion useful in the construction of bridges and railroad tracks?

Railroad tracks and bridges, for example, have expansion joints to allow them to freely expand and contract with temperature changes, as shown in Figure 1.4. 1. The result is that increased kinetic energy (increased temperature) increases the average distance between molecules—the substance expands.

How is thermal expansion high temperature?

When a substance is heated, molecules begin to vibrate and move more, usually creating more distance between themselves. As energy in particles increases, they start moving faster and faster weakening the intermolecular forces between them, therefore expanding the substance.