AWS A5.17 Groove Weld Test Procedure
The Groove Weld Test Parameters for the classification of Carbon Steel Electrodes and Fluxes for SUBMERGED ARC WELDING (SAW) including Virgin and Crushed Slag.
This is a very demanding procedure and should only be undertaken by highly trained welding professional using good quality SAW equipment and proper monitoring devices.
The AWS A5.17 groove weld test parameters described herein are to determine the tensile strength and Charpy impact toughness of the weld metal as deposited from a specific electrode-flux combination. Generally, the impact toughness is the more difficult test to pass for active fluxes, including virgin fluxes and requires careful control of the heat input, interpass temperature and bead placement.
The maximum heat input must be controlled to achieve acceptable impact toughness results. Heat input is calculated using the formula:
HI = I x V x 60
S x 1000
where: HI = Heat input (kj/in) I = amperage V = voltage S = travel speed (ipm)
Voltage and current must be monitored with calibrated equipment. Travel speed must be verified with a measuring tape and stopwatch. Temperature must be verified with a temperature measuring crayon such as a Tempilstik. Tempilstiks of 275°F and 300°F are required for this procedure. Digital infrared temperature thermometers are not recommended unless verified with a temperature crayon.
The bead sequence is important. It involves laying down 17 separate beads using the 2 bead per layer technique except on the cap layer where 3 beads are used
Welding shall start with the material at room temperature. Welding shall continue, bead by bead, until a temperature within the interpass temperature range is reached. Thereafter, production of subsequent beads may only begin when the assembly is within the interpass temperature range of 275° F -300° F.
Even when a highly trained welding professional undertakes this procedure it is still possible that the required AWS minimum requirements will be not met using either virgin or crushed slag..... in particular the minimum requirements for Charpy impact toughness.
Hence, with respect to qualifying RECRUSHED SLAG we also strongly recommend that both the Crushed Slag and Virgin Slag be tested side by side at the same time by the same professional in order to provide a valid comparison of the two SAW products.
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