A pipe offset is calculated when a pipe is altered in both the vertical and horizontal planes of a piping system. This type of occurrence is known as a "rolling offset." Following Pythagoras' theorem, the first number, or true offset, is calculated by taking the offset squared and adding the rise squared to obtain the true offset squared. Take the square root of the answer to obtain the offset.
Know MoreOnce the true offset is known, the pipe fitter can utilize a table to find out the setback and diagonal center. Most fitting constants are 45 degrees in the plumbing trade. If the fitting angle is 60 degrees, the diagonal for the pipe is equal to the true offset times 1.155. If the fitting angle is 45 degrees, the true offset is multiplied by 1.414 to obtain the diagonal. For any fitting angle that is 22.5 degrees, the true offset is multiplied by 2.613 to get the answer for the diagonal.
The setback for fitting a pipe equals the true offset multiplied by 0.577 for a fitting angle of 60 degrees. The true offset multiplied by 1.000 equals the setback for a 45-degree fitting angle. Multiply the true offset by 2.414 for the setback for a 22.5-degree fitting angle. Using the above calculations, the true offset for a 45-degree fitting is 14.42 inches and the same number for the setback.
Learn more about PlumbingTo calculate the water flow rate through a given pipe size, multiply the area of the inner cross-section of the pipe by the velocity of the water. The velocity of the water is required for this calculation.
Full Answer >The pipe-fitting formula for a 45-degree offset in plumbing is the length of a diagonal connector, known as the travel, times 0.707. To calculate rolling offset, when a pipe changes direction both vertically and horizontally, it is necessary to find the values for true offset, the setback and the diagonal.
Full Answer >To determine the correct size of PVC pipe for a project, use a pipe size chart to determine the pipe size that fits the supply line. The size chart can be used on the pipe that is being replaced, or can be matched at a home improvement store.
Full Answer >To sweat a copper pipe, cut and clean the end of the pipe, then apply a soldering paste to the end, and seal the new fitting with a blow torch. You need a hacksaw, pipe cleaning tools, a flux brush, soldering materials, a blow torch and a rag.
Full Answer >