LITTLE P.ENG. FOR ENGINEERING CONSULTANCY SERVICES

Most threaded joints in ASME B31.3 piping systems are made with taper threads in accordance with ASME B 1.20.1. Figure 5.1 shows a taper thread. These threaded joints are generally acceptable for Normal Fluid Service and Category D Fluid Service. Paragraph 314.1(a) states that threaded joints should be avoided in any service where crevice corrosion, severe erosion, or cyclic load may occur. Cyclic loading is not defined and this limitation is rather unclear, because all syste

Welded and brazed joints are the most commonly used methods for joining piping components because these joints are stronger and more leak-tight than threaded and flanged joints. Furthermore, they do not add weight to the piping system as flanges do, and they do not require an increase in pipe wall thickness to compensate for threading, as threaded joints do. Pipe-Weld Joint Preparation and Design Butt Welds. The most common type of joint employed in the fabrication of welded