The Marangoni effect is the mass transfer along an interface between two fluids due to the surface tension gradient (which fluid from areas with low surface tension is transferred to areas with higher surface tension). In particular, a negative value … Continue reading What is Marangoni effect in GTAW welding?
In general, butt joint welding is divided into two-sided welding welded on both sides and the back gouging must be applied due to poor welding quality at the first welding layer of the first one-sided welding. (Call completed joint penetration, See What is CJP in welding) For one-side welding method, a backing material, which is a backing material that prevents melting of molten metal, is attached to the backside of the base material, and then the welding wire is lowered to form an arc between the base material to weld the base material. Welded Chill Plate (or Permanent backing strip, … Continue reading What is Chill Plate in Welding
The socket weld is a pipe attachment detail in which a pipe is inserted into a recessed area of a valve, fitting, or flange. The joint construction is a good choice wherever the benefits of high leakage integrity and great structural strength are important design considerations. Advantages of Socket Weld Pipe Fittings The socket weld pipe fittings can be used in place of threaded fittings, so the risk of leakage is much smaller. Socket weld pipe need not be beveled for weld preparation. The weld metal can not penetrate into the bore of the pipe. Construction costs are lower than with butt-welded joints due … Continue reading Why is the Gap needed on Socket Welds
Welding fabrication involves several operations which might have a significant ergonomic impact.This article aimed at providing an overview on these typical activities, and the most confusion on terminology of Partly Mechanized and Fully Mechanized processes during identify the welding personnel as a WELDER or WELDING OPERATOR? The role of welding personnel in welding processes: Based on the level of automation, processes are defined by applicable industrial standards as:– Manual processes, involving welders;– Partly mechanized (or semiautomatic) processes, involving welders;– Fully mechanized (or automatic) processes, involving welding operators;– Automatic and/or robotized processes, involving welding programmers, operators.Depending on the industrial needs, some … Continue reading What is different between Partly mechanized and Fully mechanized welding process?
This question has been made through every year when the engineer concerning about ferrous or non-ferrous metal during making of welding procedure, permanent joint qualification or corrosion calculation. This article gives an overview of ferrous metals, what they are and how they’re made. There are several common types of ferrous metals such as mild steel, stainless steel and cast iron. Ferrous metals are highly versatile. Read this article to learn about their applications and advantages and disadvantages of ferrous metals Did you know? Iron is the most abundant element on earth. The earth’s core consists of an iron-nickel alloy that makes … Continue reading Is Stainless Steel ferrous metal?
Following the concerns of welding defects for in-service maintenance hot works, the Mock-up test should be performed to increase the confidence level of works. See this: In-service and maintenance welding defects Mock-Up Testing ; This comes at a Mock-up Testing for In-service welding or welding On-stream … For onstream welding, while there is fluid flowing inside the pipe or equipment The most important is the safety that is not going to burn through the weld and weld it must not happen Hydrogen cracking (HIC) according to the method used to prove that the simulated welding or the Mock-up test. In conducting a mock-up test, the workpiece must look like or represent the actual work in the matter including: (1) Type ( Material Spec.), and the thickness of … Continue reading What is Mock-up test for In-service Welding
In-Service Welding Concerns; When welding, repairing or modifying pipelines or equipment that are currently being used (In-Service), the most worrying is the leak of the fluid inside. While or after doing On-line Welding. The two main reasons that cause the leak are: Burn Through: While welding at the melting area of the welding, the strength will be reduced. We may not be able to withstand the Pressure at Service value. Weld Cracking or Hydrogen Induced Cracking (HIC) from welding. The additional concern in welding is the cooling rate. Since the inside of the pipe or equipment has fluid flow, it may … Continue reading In service and maintenance welding defect
Below is a summary of the material changes made to the 2020 edition of AWS D1.1. Format changes – moving to 11 clauses from 9. This change was made to improve clarity and it includes the addition of reference tables, formatting to mimic the normal progression of welding procedure qualification, as well as other updates to improve ease of use. Additional requirements are added when using shielding gases for use with prequalified welding procedures. Revision of the requirements for the qualification of WPSs using waveform technology (Heat input, auto-calculation, and record.) Revisions made to the qualification requirements for inspection personnel … Continue reading AWS D1.1 2020 Changed notes
Slip-on Flanges Limits per ASME B31.3; In the ASME B31.3 Piping Code, restrictions on slip-on flanges are specified as follows: Use welding Double-Welded for Service that causes Severe erosion, Crevice corrosion, and Cyclic loading Service that is combustible, toxic and harmful to people Service at temperatures below -101 C 2. Do not Slip-on Flanges with Service with high pressure than ASME B16.5 Flange Class 2500. 3. Avoid Slip-on Flanges with Service that changes the temperature up – downtime (, Many the Large Temperature Contact of Cycle), especially with Flanges are not covered Insulation, which will cause a change in the temperature of the Flange and. Pipe quickly and may lead to thermal fatigue cracking … Continue reading Slip-on Flange ASME B31.3 limitation