Hydraulic Piping Systems Mechanical Joint - vs - Welded

摘要

The following discussion will point out the differences between a welded piping system and a non-welded piping system. The first part will review welded systems and the welding process. The second part will compare those findings to a non-welded, mechanical joint system. Traditionally welding has been used to join two pipes together. This practice has been used for years with varying degrees of success. The welded connection produces many problems due to the many inherent variables in the process. If the variables are analyzed, and if the welding procedures are followed, and if the pipes are installed, x-rayed and cleaned properly, welding can be utilized successfully. The welding of pipe requires planning, special equipment, skilled technicians, adequate ventilation, isolated work areas, fire prevention, inspection and chemical cleaning. These requirements equate to extra time and money. The welding process typically begins with the selection of the following: 1. Qualified welding procedures 2. Specific welding techniques and material to be used 3. Procedures to qualify and re-qualify welders and welding inspectors 4. Proper welding equipment to suit the application 5. Finding knowledgeable cleaning / flushing companies Even if this selection process is performed with great care and detail, there are still many uncertainties that need to be addressed. First, welding engineers and project managers must clarify welding specifications, procedures and resources. When selecting the welding equipment, the engineer must have knowledge of power sources, specific techniques (i.e. Shielded Metal Arc, Gas Tungsten Arc, Gas Metal Arc, or Flux Cored Arc welding, etc.) and have a working knowledge of how to apply these techniques.