Effect of welding sequence and welding current on distortion, mechanical properties and metallurgical observations of orbital pipe welding on SS 316L

Abstract

Orbital pipe welding was often used to manufacture piping systems. In orbital pipe welding, a major challenge is the welding torch’s position during the welding process, so that additional methods are needed to overcome these challenges. This paper discusses the influence of welding sequence and welding current on distortion, mechanical properties and metallurgical observations in orbital pipe welding with SS 316L pipe square butt joints. The variation of the orbital pipe welding parameters used is welding current and welding sequence. The welding current used is 100 A, 110 A, and 120 A, while the welding sequence used is one sequence, two sequences, three sequences, and four sequences. The welding results will be analyzed from distortion measurement, mechanical properties test and metallurgical observations. Distortion measurements are made on the pipe before welding and after welding. Testing of mechanical properties includes tensile tests and microhardness tests, while metallurgical observations include macrostructure and microstructural observations. The results show that maximum axial distortion, transverse distortion, ovality, and taper occurred at a welding current of 120 A with four sequences of 445 µm, 300 µm, 195 µm, and 275 µm, respectively. The decrease in ultimate tensile strength is 51 % compared to the base metal’s ultimate tensile strength. Horizontal and vertical microhardness tests show that welding with one sequence produces the greatest microhardness value, but there is a decrease in the microhardness value using welding with two to four sequences. Orbital pipe welding results in different depths of penetration at each pipe position. The largest and smallest depth of penetration was 4.11 mm and 1.60 mm, respectively

Indentifying the effect of micro friction stir spot welding (µFSSW) parameters on weld geometry, mechanical properties, and metallography on dissimilar materials of AZ31B and AA1100

“…Measurements are made at the top and back of the weld. This method has also been used by researchers in previous research on orbital pipe welding [27]. At the top of the plate, it can be seen visually that the shoulder diameter begins to form at a plunge depth of 400 microns and increases at a plunge depth of 600 microns.…”

Identifying the influence of orbital pipe welding parameters on mechanical properties using SS316L pipe

“…According to a research report [13], orbital pipe welding's pulse current approach can improve AISI 304L pipes' mechanical qualities. Studies [14] show that the sequence approach improves SS316L pipe mechanical qualities, particularly tensile strength, and hardness at various pipe places. A study [15] noted that operating factors significantly affect bead shape and tensile characteristics.…”

Examining the hysteresis loop of the SS316L U-shaped pipe considering ratcheting behavior

“…Notably, the applucations of pipes through which the uids ow are signi cant in the mechnical industry. Among such pipes, the SS316L pipes have received much attention due to their remarkable physical and chemical properties in various applications [27][28][29]. SS316L pipe is constituted from a seamless steel material and has been one of the main components in the engineering structures since many years ago [30].…”