Piping Technology highly recommends that our customers thoroughly understand the uniqueness of pipe expansion joints and their application. The following safety recommendations are paraphrased from the Fifth Edition of The Standards of the Expansion Joint Manufacturers Association, 1980.
SAFETY RECOMMENDATIONS FOR PIPING SYSTEMS CONTAINING BELLOWS EXPANSION JOINTS
Bellows pipe expansion joints are employed in piping systems to absorb differential thermal expansion while containing the system pressure. They are being successfully used in refineries, chemical plants, fossil and nuclear power plants, shipboard applications, heating and cooling systems, pulp and paper plants, and cryogenic plants. Typical service conditions range from pressures of full vacuum to 1,000 psig (70 kg/cm3) and -420F to +1,800 F (-251C to +968 C). Thus, pipe expansion joints must be specified as a highly engineered product. They cannot and should not be purchased and used as commodity items if the pipe expansion joints are to perform their intended function safely and reliably. The system operating requirements, the pipe expansion joint design and manufacturing quality, the installation, test and operating procedures must all be considered for all pipe expansion joint installations.
Unlike most commonly used piping components, a bellows is constructed of relatively thin gauge material in order to provide the flexibility needed to absorb mechanical and thermal movements expected in service. This requires design, manufacturing quality, nondestructive examination, handling, installation and inspection procedures which recognize the unique nature of this product.
In general, the most reliable and safe bellows pipe expansion joint installations have always involved a high degree of understanding between the user and manufacturer. With this basic concept in mind, the following recommendations are given in order to better inform the user of those factors which many years of experience have shown to be essential for the successful installation and performance of piping systems containing bellows pipe expansion joints.