Steel pipes and tubing are used all over the world to build and support construction and building structures. The strength and capability of these items is determined by its ability to withstand pressure in normal or reasonably stable environments. This durability is calculated using proportions known as burst pressure or yield points. The specific point at which the tube will fail cannot be determined as one cannot predict the exact environment or usage in which the device will be placed.
Identify the general formula. Collapse pressure is defined as 2 times the burst pressure times wall thickness times (outer diameter minus wall thickness) divided by outer diameter squared. Recognize there are variants of this formula for different objects, such as screens, PVC (polyvinyl chloride) pipes, and steel casing. For example:
Collapse pressure for 316L material is 2 times 22,200 times 0.25 times 0.035 times 10,400 – 0.25 times 0.035 divided by 10,400 squared equals 16,900.
Use a corrugated factor for screens. Compute the collapse strength of a screen as 24 times 3 times 10 raised to the 7th power times moment of inertia divided by (width of wire on external face – inches plus slot width of screen-inches) times mean diameter of the screen-cubed.
Compute the collapse strength of a PVC pipe using Poisson’s ratio. Use the formula collapse pressure PVC equals (2 times 4 times 10 raised to the 5th power divided by 1 minus 0.33) times 1 divided by (outside diameter of pipe divided by wall thickness) times (outside diameter of pipe divided by wall thickness times minus 1) squared.
Calculate collapse strength of steel casing. Use the formula, (2 times 3 times 10 raised to the 7th power divided by 1 – 0.3 squared) times (1 divided by (outside diameter of pipe divided by wall thickness times minus 1) cubed.
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