TABLE OF CONTENTS The support scheme of a piping system is critical to its function and the equipment it is connected to. When equipment and piping increase in temperature, they expand; likewise, for cold temperatures, they contract. We have outlined the various failure mechanisms in piping in the last two chapters. Now we will address what the plant engineer and inspector routinely work with pipe supports.
Spring supports sustain a pipe that has undergone displacement. Simple supports are no longer useful if the pipe rises off and loads are transferred to other supports or fragile equipment nozzles. To ensure support for the pipe as it moves, a support to compensate movement is desired. One very practical device for this is the spring.
Springs come in two basic types variable springs and constant springs. The variable spring, which is by far the most common, provides loading to a pipe at a constant spring rate, lb/in. (N/mm), but the amount of force required to compress the spring varies with the amount of compression-hence the name variable spring. The constant spring is a spring that will provide the same spring rate for any force great enough to cause initial displacement. Constant springs are used in critical installations where loadings or displacements induced on or by the piping system are critical. We will go into more detail later in the chapter.
Variable springs are used where a variation in piping loads can be tolerated. They are easier to adjust and more forgiving than...
