Pipe with Dual Grade

What is Dual Grade Stainless Steel Pipe: According to ASME BPVC Section II states that control the material characteristics such as mechanical properties (Mechanical Properties), chemical (Chemical, COMPOSITION), the Heat Treatment Through the provision of Grade supplies more than one Grade will be identified as Dual or Multiple Grade. For example, Dual Grade Stainless Steel Pipe, ASME SA-213 TP316 / 316L: Looking at the ASME SA-213 spec, you can see that 316L Low-Carbon Grade is defined to have the Carbon content lower than 316 Standard Grade, and at the same time requires that 316L have Min. Tensile Strength and Min. Yield Strength be lower. (Steel in general, if having less Carbon, will also have low Tensile Strength) This … Continue reading Pipe with Dual Grade

Tension Test Acceptance Criteria for Welding Procedure Qualification

Tension Test Acceptance Criteria for Welding Procedure Qualification per ASME IX;  To qualify the welding procedure according to the ASME Section IX, the mechanical properties of the test coupon must be tested. Tension Test, which is the test of the strength of the weld by The principle of ASME is that Weld Metal must be stronger than or equal to the strength of Base Metal. Therefore, the result of the Tension Test will have Acceptance Criteria as follows. The workpiece is torn/break at Base Metal: Ultimate Tensile Strength (UTS) or Failure Stress of the workpiece must be greater than 95% … Continue reading Tension Test Acceptance Criteria for Welding Procedure Qualification

The project requires Killed Steel treatment on Pipe, Plate MTC.

Fully killed is the term to describe de-oxidized steel. After the steel is made, it is then poured into the continuous caster to make a long slab of steel. Think of a sausage maker – molten steel goes in at the top and rectangular slab comes out the bottom. This is called casting. During casting, small carbon monoxide bubbles can form between the steel grains if the oxygen is not removed. If you’ve ever painted a door and seen bubbles in the paint once you apply it you’ll recognize the similarities. To stop these bubbles appearing you paint slower, but … Continue reading The project requires Killed Steel treatment on Pipe, Plate MTC.

Stainless steel 347H and PWHT

”In the welded condition many stainless steels are susceptible to rapid intergranular corrosion or stress corrosion cracking. This is because the heat from welding sensitizes the base metal heat affected zone (HAZ) and the weld. Sensitization is the condition where chromium carbide precipitation at the grain boundaries (from a heating process, e.g., welding, hot forming, hot bending, service temperature, etc.) reduces the amount of chromium in solution in the stainless steel. The temperature range for sensitization to occur for austenitic stainless steels is approximately 700 °F to 1500 °F. Since the carbides precipitate in the HAZ or weld deposit at … Continue reading Stainless steel 347H and PWHT

Change electrode manufacture, vendor in welding WPS.

If welding is to be performed according to a welding procedure specification, it is possible that changing the electrode manufacturer will invalidate the approval of the procedure to the code/standard on which it was based. The manufacturer or ‘trade name’ of the electrode can be classed as an essential variable in a given weld procedure. The extent to which re-qualification is necessary will vary from code to code. For example, in EN ISO 15614-1[1] and in the UK standard BS 4515:2004[2], approval is only restricted to the specific make of electrode if impact testing is required as part of the procedure qualification. On the … Continue reading Change electrode manufacture, vendor in welding WPS.