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Many welding applications — especially critical welds in industries such as structural construction, oil and gas and shipbuilding — require preheat. Minimizing the temperature difference between the arc and the base material slows the weld cooling rate and lowers hydrogen, two factors that help reduce the risk of cracking and the potential for a failed weld. Determining if a welding application requires preheat depends on several factors, including the type and thickness of the base material. The welding code typically dictates the use of preheat. To meet the requirements of the code, the welding procedure specification (WPS) for the job will outline the minimum and maximum preheat temperatures as well as the necessary duration of preheating. Often, a part must stay within a specific temperature range for a certain amount of time — such as between 250 degrees and 400 degrees Fahrenheit for 30 minutes — before welding can start. Welders typically must monitor the base metal’s temperature between weld passes to ensure the material remains within the required range. Common temperature verification tools include crayons, thermocouples, infrared thermometers and thermal imaging cameras. #welding #qualitycontrol #weldingengineer #carbonsteel #wps #manufacturingtechnology #oilandgasindustry #rotatingequipment

One job often leads to another. Recently we went to change a valve and ended up rebuilding the entire nozzle. Our staff of professional tradespeople will always go the extra mile to identify and correct problems in the field. #millwright #pipefitter #boilermakers #industrialcontractor #mechanicalcontractor #vessel #welding #repair #maintenance #construction #chemicalvalley #oilandgas #planning #installation #facilitymaintenance

Pipe – General Welding Requirements If you look into various sections of documents such as ASME B31, you will find categorization of steel alloy materials by weld numbers. The purpose of the Weld Number tables is to support a numbering system methodology to make welding procedure creation and welding procedure management much easier as well as cheaper The P number is used to group similar Base Metals, allowing the qualification of an entire assortment of metals instead of just one. The arrangement is to group by material and assign P Numbers accordingly. We start with P Number 1 and its assignment to Carbon Manganese or Low Carbon Steel base metals. The P numbers reduce the number of welding procedures and welder performance qualification tests needed to qualify a wide range of materials. The base metal grouping scheme also consists of the P numbers and Group Numbers. P numbers are assigned in Section IX of the Boiler and Pressure Vessel Code. Qualification of a weld procedure for a specific weld procedure qualification purpose; they group materials based on weldability, composition and other mechanical properties. The metal coalescence is produced by heat from an electric arc maintained between the tip of a consumable electrode  and the surface of the base material in the joint being welded. Shielded metal arc welding (SMAW), informally known as stick (rod) welding, is a manual arc welding process that uses a consumable electrode covered with a flux to lay the weld. Stainless steel, carbon steel, alloy steel and cast steels are often welded using this method. (A welding voltage of about 15–45 V and welding current in the range of 10–500A are generally utilized to produce an arc with a temperature of 5000°C.   The equipment for completing SMAW is basic and the method is straightforward enough to use outside the shop as opposed to other methods requiring shielding gas, which are unsuitable in wind. It is possible to weld a wide variety of metals by changing only the electrode materials. Therefore, the SMAW is the most commonly used arc welding technology. However, the arc time factor of SMAW is relatively low due to the time required for chipping away slag after welding and changing the electrodes. Welders have to pass a welding test which is documented in the Welder Qualification Record. (WQR)   Process Piping  2004 Charles Beck IV, McGraw Hill   #pipe  #pnumber #smaw #alloy #welder #wqr #metals #arc #shielding #gas #temp #rod

𝗛𝗲𝗮𝘁 𝗔𝗳𝗳𝗲𝗰𝘁𝗲𝗱 𝗭𝗼𝗻𝗲 𝗖𝗿𝗮𝗰𝗸 The heat affected zone (hashtag #HAZ) of a weld is not limited to the weld itself but to the immediate area of parent material surrounding the weld. A HAZ crack can originate at the toes of the weld or a few millimeters from the weld altogether. The most common causes for this type of crack are: excess hydrogen, high residual stress levels on the weld, and high carbon content on the base material. 𝑻𝒐 𝒎𝒊𝒏𝒊𝒎𝒊𝒛𝒆 𝒕𝒉𝒆 𝒔𝒖𝒔𝒄𝒆𝒑𝒕𝒊𝒃𝒊𝒍𝒊𝒕𝒚 𝒐𝒓 𝒑𝒓𝒆𝒗𝒆𝒏𝒕 𝑯𝑨𝒁 𝒄𝒓𝒂𝒄𝒌𝒔 𝒄𝒐𝒏𝒔𝒊𝒅𝒆𝒓: 1. using low hydrogen electrodes 2. pre-heating the base material 3. slow cooling the base material after welding 𝑻𝒉𝒆 𝒇𝒊𝒈𝒖𝒓𝒆 𝒔𝒉𝒐𝒘𝒔 𝑯𝒆𝒂𝒕 𝒂𝒇𝒇𝒆𝒄𝒕𝒆𝒅 𝒛𝒐𝒏𝒆 𝒄𝒓𝒂𝒄𝒌 𝒊𝒏𝒅𝒖𝒄𝒆𝒅 𝒃𝒚 𝒉𝒚𝒅𝒓𝒐𝒈𝒆𝒏. 𝑻𝒉𝒆 𝒄𝒓𝒂𝒄𝒌 𝒐𝒓𝒊𝒈𝒊𝒏𝒂𝒕𝒆𝒔 𝒂𝒕 𝒑𝒐𝒊𝒏𝒕 𝒐𝒇 𝒉𝒊𝒈𝒉 𝒔𝒕𝒓𝒆𝒔𝒔 𝒂𝒔 𝒉𝒚𝒅𝒓𝒐𝒈𝒆𝒏 𝒅𝒊𝒇𝒇𝒖𝒔𝒆𝒔 𝒐𝒖𝒕 𝒐𝒇 𝒕𝒉𝒆 𝒘𝒆𝒍𝒅 𝒂𝒏𝒅 𝒉𝒆𝒂𝒕 𝒂𝒇𝒇𝒆𝒄𝒕𝒆𝒅 𝒛𝒐𝒏𝒆. #Welding #HAZ #Metallurgy #Quality #Inspection #Crack #Construction #OilandGas #Piping #Mechanical #Projects #Preheating #Inspector #Inspection #welding_imperfections

The manual Gas Metal Arc Welding (GMAW) process also known as Metal Inert Gas (MIG) welding. When performing this process it is important to use the correct weld voltage and wire feed speed settings for the thickness and type of material you are welding as well as gas considerations. However that is the easy part of the manual process. Utilizing correct techniques to control factors such as work angle, travel angle, travel speed and contact tip to work distance (CTWD) play crucial roles in making sound welds. Work and travel angles can affect penetration and appearance. Possibly causing undercut, cold lap, and uneven weld legs. Travel speed affects penetration and heat input. Faster speeds will have lower penetration while slower speeds will have more penetration but also higher heat input and broaden the heat affected zone around the weld. CTWD controls arc length which directly affects amperage and penetration. A longer CTWD will have lower amperage and penetration. Alternatively a shorter CTWD will have higher amperage and thus greater penetration. Control of all these factors come together with weld settings and gas selection to make the manual GMAW process a highly skilled endeavor. #fabrication #manufacturing #gmaw #welding #weldingtechnology #production #welder #mig #engineering

pipe welding system debugging 🤓... The problem is the quality of welding system is rejected by QC 🤔...the solution is reconfiguration od frequency 🤓 #electricalengineering #electricalwork #pipewelding #roll_forming

Friction welding of drill pipe is an advanced welding technology used in the manufacture of drilling equipment in the oil and gas industry. It is mainly used to connect pipe sections of drill pipe to form a continuous drill pipe column. Friction welding (FW) is a solid-state welding method that does not involve filler materials or shielding gases. The friction heat generated by the rotational motion makes the two metal surfaces reach a plastic state, and then welds under pressure. The drill pipe after welding is subjected to necessary mechanical processing, such as turning the end face, to ensure dimensional accuracy and surface finish. Non-destructive testing (NDT), ultrasonic testing (UT) or radiographic testing (RT) are also required to verify the welding quality. The application of friction welding technology in drill pipe manufacturing can improve welding efficiency, reduce energy consumption, and the welded joint has high strength and good reliability. It is particularly suitable for drill pipes that need to withstand high pressure, high temperature and complex underground conditions. In addition, since the metal does not melt during the welding process, the possibility of welding defects is reduced, and the overall performance and service life of the drill pipe are improved. #drillpipe #pipe #drawworks #BOP #topdrive #TDS #usedrig #drillingrig #mudpump #pump #workoverrig #750hp #industrialpower #bop #Reliability #PrecisionPerformance #OilDrilling #QualityProducts #OilandGas #Engineering #workover #workoverrig #oilindustry #oilfield #drilling #oildrilling #energyindependence #oil

back side gas purging with tgx electrode

Pipe welding involves joining two pieces of metal tubing or pipes together. This process is crucial in various industries, such as oil and gas, construction, and manufacturing, because it ensures the integrity and strength of the piping systems that transport fluids, gases, and sometimes solids under varying pressures and temperatures. The quality of pipe welding is paramount for safety, efficiency, and compliance with industry standards and regulations. There are several techniques and methods used in pipe welding, each suited to different types of materials, pipe sizes, and project requirements. Some of the most common pipe welding methods include: 📍 Shielded Metal Arc Welding (SMAW): Also known as stick welding, it uses a consumable electrode coated in flux to lay the weld. This method is versatile and widely used for its simplicity and effectiveness in outdoor conditions. 📍 Gas Tungsten Arc Welding (GTAW), or TIG welding: This method uses a non-consumable tungsten electrode to produce the weld. It is highly valued for its ability to produce high-quality, precise welds on a variety of metals, including thin materials. 📍 Gas Metal Arc Welding (GMAW), or MIG welding: This uses a continuous, consumable wire electrode fed through a welding gun. It's popular for its speed and ease of use, especially on thicker materials. 📍 Flux-Cored Arc Welding (FCAW): Similar to MIG welding, but it uses a special tubular wire filled with flux. It can be more effective than MIG in outdoor applications or when welding thicker materials. 📍 Submerged Arc Welding (SAW): This method uses a consumable electrode under a blanket of flux. It's known for high deposition rates and deep weld penetration, often used in industrial applications requiring heavy-duty welding. Each of these methods has its advantages, limitations, and suitability for specific applications. The choice of welding technique depends on factors such as the type of pipes (material, thickness, diameter), the working environment (indoors, outdoors, underwater), and the specific requirements of the piping system (pressure, temperature, fluid type). Which technique do you use commonly in your industry? Share it in the comments. Here's a guide on different pipe welding procedures. Do check it out. For more such insightful content, follow Jefy Jean A

𝐇𝐨𝐥𝐥𝐨𝐰 𝐁𝐞𝐚𝐝 (𝐇𝐁) 𝐃𝐞𝐟𝐞𝐜𝐭 𝐢𝐧 𝐏𝐢𝐩𝐞𝐥𝐢𝐧𝐞 𝐖𝐞𝐥𝐝𝐬 ￫ Elongated pore or void located in the root pass of a girth weld in pipelines ￫ Oriented linearly along the weld direction  ￫ Oil and gas pipelines are commonly welded using a manual metal arc welding technique using cellulosic electrodes. ￫ Cellulosic electrodes provide good penetration and high travel speeds and hence high productivity. 𝙀𝙭𝙘𝙚𝙨𝙨𝙞𝙫𝙚𝙡𝙮 𝙝𝙞𝙜𝙝 𝙬𝙚𝙡𝙙𝙞𝙣𝙜 𝙨𝙥𝙚𝙚𝙙 𝙖𝙣𝙙 𝙘𝙪𝙧𝙧𝙚𝙣𝙩 𝙘𝙖𝙣 𝙘𝙖𝙪𝙨𝙚: ￫ Inadequate gas escape from weld pool, trapping bubbles 𝗠𝗲𝗰𝗵𝗮𝗻𝗶𝘀𝗺: ￫ High speed welding doesn't allow time for gas bubbles to escape ￫ Bubbles trapped as gas pores during solidification - Liquid metal ahead of solidification front gets supersaturated with gas pores, making elongated pore along with weld direction 𝙃𝙤𝙡𝙡𝙤𝙬 𝘽𝙚𝙖𝙙 (𝙃𝘽). #HollowBead #pipeline #radiography #weldingdefects #WPS #ITP #inspection #PipingDesign #ASMECode #EngineeringExcellence #QualityAssurance #QualityControl #QualityManagement #ContinuousImprovement #CustomerSatisfaction #OperationalExcellence #EngineeringExcellence #Innovation #MaterialScience #IndustryAdvancements #QAQC #QA #QC #asme #welding #weldinginspection #weldingengineer #weldinginspector #engineering #construction #fabrication #piping #steel #api #aws #data #code #standard #quality #qualitycontrol #qualityassurance #pressurevessels #tanks #oilandgas #powerindustry