Application Handbook MECHANISED AND ORBITAL TIG XA00131620
Limitless possibilities Welding two tubes of different sizes is easily carried out using fillet welds. Boiler tubes are often welded using AVC and weaving. Copper nickel is a sensitive alloy and is difficult to weld manually Jointed tubes of varying quality, such as low-alloy steel as opposed to stainless teel. Heavy wall thickness to a maximum of 80 mm in low-alloy, stainless, duplex or super-duplex steel can be welded with ESAB s Narrow Gap TIG. Quality meets quality You can weld the tube to the inside of a plate using an A22 inner welding torch and avoid crevice corrosion When welding Titanium you can choose from our enclosed or open heads with trailing shoe, to provide a better gas shield. Our welding heads are ideal for welding thin or thick stainless steel tubes. The T-component welded by upsetting the main tube is a good and simple option Using the A22 tube-to tubesheet welding head, you can weld all types of tube geometry; flush, recessed, extended or protruding from the sheet.
Halve the welding time for thick pipes with Narrow Gap welding. The picture shows the crosssection of a carbon steel tube. Using the automatic weaving and arc length control (AVC), you can quickly fill large seams in thick walled tubes. You should use a single U-joint and filler wire for thicknesses of more than 3 mm. 15 mm gap to the flange is sufficient for the PRB and PRC heads. Precise seam preparation guarantees a successful final result As with all materials handling, preparation before welding plays a crucial part in the final result. The surfaces to be welded must be completely free of oil and dirt. The seams must be thoroughly prepared technically, i.e. the type of material and its thickness. BUTT JOINT U-JOINT NARROW GAP JOINT Butt welding with a square edge can be used on material with a maximum thickness of 3 mm. For material thicknesses of more than 3 mm, seam preparation is necessary. To ensure a good root bead we recommend a U-joint. If you wish to halve the welding time on tubes with wall thicknesses of more than 6 mm, we recommend a Narrow Gap joint, which also reduces the amount of filler metal, needed. V-JOINT It is possible to weld an open V-joint but there is always a greater risk of root defect. A V-joint without gap can also be welded. However, this is not recommended because of the risk of inadequate penetration in the root.
Segment: Food, beverage and dairy Treatment, conditioning or storing of food and mineral water processing Typical material is Stainless steel 304 and 316L Orbital TIG is well suited to meet the more and more stringent hygiene requirements The indisputable choice for production of distribution links between the different stages of food processing, both as sterilisation lines and cooling lines. Aristo MechTig C2002i PRH, PRB, PRD 160 6.0-220 mm 0.8-2.5 mm MechControl 2 + Aristo MechTig 4000i PRH, PRB, PRD 160 6.0-220 mm 0.8-3.0 mm MechControl 4 + Aristo MechTig 4000i PRH, PRB, PRD 100 6.0-220 mm 0.8-3.0 mm PRD 160 Segment: Chemical industry Tube-to-tube and tube-to-fitting welding in chemical plants. Pre-fabrication of components Typical material is Stainless steel 304 and 316L The automatic tube welding machines weld perfectly in confined spaces. Aristo MechTig C2002i PRB, PRD 160 50-1000 mm 2.0-2.5 mm MechControl 2 + Aristo MechTig 4000i PRB, PRD 160 50-1000 mm 2.0-5.0 mm MechControl 4 + Aristo MechTig 4000i PRB, PRC, PRD 100 50-1000 mm 2.0-5.0 mm PRD 160
Segment: Pharmaceutical / biochemistry Pharmaceutical products, which require strict and regulated handling. Typical material is Stainless steel 304 and 316L Quality considerations are extremely critical as these products can be affected by cross contamination, microbial growth, efficacy issues and external sources. A precision orbital welding equipment can meet these stringent demands and the welding result can be achieved by using closed chamber-welding heads and providing an optimum weld head protection during welding. Aristo MechTig C2002i PRH, PRB, PRD 160 6.0-220 mm 0.8-2.5 mm MechControl 2 + Aristo MechTig 4000i PRH, PRB, PRD 160 6.0-220 mm 0.8-3.0 mm MechControl 4 + Aristo MechTig 4000i PRH, PRB, PRD 100 6.0-220 mm 0.8-3.0 mm PRD 160 Segment: Power generation / Boiler Steam generators and waste heat boiler fabrication. Production of coiled pipes Welding of return bends to finned tubes Tube or collector welding High pressure preheating units Endless tube fabrication etc. Typical material is Cr-Mo, carbon steel The use of Orbital TIG will increase the productivity (up to 50%) compared to other methods, even under restricted accessibility A constant ISO documented quality. MechControl 2 + Aristo MechTig 4000i PRB, PRD 160 25-1000 mm 2.5-5.0 mm MechControl 4 + Aristo MechTig 4000i PRB, PRC, PRD 100 25-1000 mm 2.5-5.0 mm PRD 160
Segment: Shipbuilding Cooling lines for ship motors Tubing systems for loading/unloading of liquid or gaseous media to be transported in LNG tankers Typical material is stainless-carbon steel, Cu-Ni The highly corrosive seawater is generally transported in tubes of special Copper/Nickel alloys. High quality welding Aristo MechTig C2002i PRB, PRD 160 25-168 mm 2.0-2.5 mm MechControl 2 + Aristo MechTig 4000i PRB, PRD 160 25-168 mm 2.0-5 mm MechControl 4 + Aristo MechTig 4000i PRB, PRC, PRD100 & 160 25-168 mm 2.0-10 mm Segment: Oil and Gas / Offshore Welding of high nickel content alloy tube and piping. Pipelines transporting highly corrosive materials. LAY barge pipe welding of offshore pipelines. High-pressure oil refinery piping Tube fabrication Repair & maintenance of boilers and pressure vessels Typical material is Carbon steel and Duplex High quality welding MechControl 2 + Aristo MechTig 4000i PRB, PRD 160 25-1000 mm 1.6-5 mm MechControl 4 + Aristo MechTig 4000i PRB, PRC, PRD 100 25-1000 mm 1.6-50 mm PRD 160
Segment: Nuclear Repair and maintenance High pressure piping repair Steam generator replacement Valve seat cladding Chrome-under pipe cladding etc. The current trend is for plants to outsource repair and maintenance to specialist contractors Typical material is stainless steel 347 High quality welds MechControl 4 + Aristo MechTig 4000i PRB, PRC, PRD 100 25-508 mm 2.0-25 mm PRD 160 Segment: Aerospace Joints in the cramped quarters of modern flight transports, like planes and shuttles Joining of Titanium and Aluminium tubes Automated repair of turbine components Typical material is Stainless steel, Titanium and Aluminium The risk for human lives in case of a failure of critical applications, forces the use of precision orbital welding tooling. Aristo MechTig C2002i PRH, PRB 6.0-50 mm 0.5-2.0 mm MechControl 2 + Aristo MechTig 4000i PRH, PRB 6.0-50 mm 0.5-2.0 mm MechControl 4 + Aristo MechTig 4000i PRH, PRB 6.0-50 mm 0.5-2.0 mm
Segment: Semiconductors Joining of high purity tubing in the construction of semi-conductor chip manufacturing facilities. Typical material is Stainless steel 304 and 316L High demands for purity in the chip manufacturing process. Specialised orbital welding systems for welding in a clean room environment without generating unacceptable levels of particles. Aristo MechTig C2002i PRH 6.0-25 mm 0.5-2.0 mm MechControl 2 + Aristo MechTig 4000i PRH 6.0-25 mm 0.5-2.0 mm
CASE STORY Welding of heat exchangers at the chemical plant Azomures in Romania Hastalloy C276, Tube ID-27 mm Description Azomures used to buy heat exchangers and then produce by themselves. This resulted in lots of repairs due to hot cracking. By investing in a Mechanised TIG equipment from ESAB they are now producing heat exchangers on site. They have increased the quality and reduced the production time! There are mainly four different ways of welding tube-to-tube sheets. The application used here is where the tube is applied at the back of the tube sheet. The tool was made to weld internally at the back of the 300 mm tube sheet. The internal tube diameter is 26.7 mm and the wall thickness including the backing that needed to be melted is 2.9 mm. Contents ESAB power source, designed for tube-to-tube joining. The whole process can be controlled with this programmable power source and the programs can be stored in the internal memory. POC welding head fitted with PIB 20-30 internal bore welding torch. PRB 17-49 and PRB 33-90 welding heads (covering tube dimensions between 17-49 and 3.90 mm outer diameter). MEI 21 wire feed unit. Advantages Economy: the price for new pipes and the equipment was lower than for buying a new exchanger. The synchronised pulsing makes it possible to control the heat input and minimises the risk of heat cracks. No more repair due to hot cracking. Improved ergonomics/accessibility. The automatic tube welding machines weld perfectly in confined spaces. The customer can weld from the front. Better ergonomics has resulted in increased productivity. Increased weld quality. The same parameters are used to achieve same quality weld time after time. No need for filler wire as the PIB internal bore welding tool is used. The same set-up to be used after the first weld for the balance of the welds.
CASE STORY contribution from Derek Harvey, ESAB UK Manufacturing of body scanners Material: stainless steel Description The customer was manufacturing the scanners in various sizes, using hand welding, but orders were growing and production had to be made faster. The welding on the end cap seam on the inside and outside at both ends is critical as sensitive components could be damaged if too much heat was applied. One of the A25 heads is used for the root run and both for the following fill runs. The GMD system keep the head aligned during the weld cycle and the cameras allowed the operator to continuously monitor the weld and ensure that it was on line for the capping run. The vessels are mounted on roller bed set, and rotation of the workpiece and speed is set at the power source and kept constant during the weld, thanks to the control system. To prevent hold-ups waiting for a crane to turn the vessel to allow it to be welded at both ends, the roller beds are mounted on a turntable that will turn the job through 180 degrees. Advantages The installation has given an increase in productivity and quality, and the customer has ordered more systems as a result. Contents 2 pcs ESAB power source 2 pcs A25 welding head with wire addition, AVC and weave GMD guidance with 300 mm slides, modified to give X, Y and Z movement CaB 300 to mount the heads Special bracket arrangement to mount the equipment and give a third axis movement ESAB (PEMA) 5 ton roller beds on a special rotating base, driven by the power source and PAL3. Colour camera and monitors to view the weld when the head is at the top of the vessel.
CASE STORY contribution by Patrik Persson, ESAB Sweden Natural gas filling stations Processkontroll AB, Sweden Material: stainless steel Description The use of natural gas is increasing. The environmental aspect is becoming more and more an issue and LNG is now used as source of energy in many areas, e.g. as fuel for cars and buses. Within EU it has been decided that year 2020 at least 20% of all fuel for vehicles shall come from alternative energy sources, whereof 12% shall be natural gas. Today there are more than 50 natural gas filling stations in Sweden, the goal is to have 100 stations by the end of year 2007. Germany currently has about 550 LNG filling stations. Processkontroll AB, a Swedish company, has a long history of building LNG tank installations. They take responsibility for the entire project. They build the station, which is their own design and supply a turnkey package. The pipes are in stainless steel in dimensions from Ø16 mm and upwards. The pressure in the pipes in an LNG filling station can be up to 300 bars and the gas in the dispenser has a pressure of 230 bars. Contents ESAB power source with cooling unit OCF 2M ESAB welding head PRH 6-76, water-cooled, for welding of tube diameters from 6-76 mm. Advantages High precision and high security when welding the pipes together Easy to use. Quick service when needed.
CASE STORY From Soldering to Welding Orbital TIG-welding of Cunifer pipes at Finnish shipyard Description One material often used in a modern ship is copper nickel alloys traditionally considered to be rather demanding due to thermal properties of copper. It is difficult to get a stable weld-pool and weld without a lack of fusion. Those problems belong to yesterday at Kvaerner Masa-Yards (KMY) in Finland Orbital TIG welding was the key to improved quality and increased productivity in welding of copper-nickel piping. Material thickness is less than 3.0 mm. Combined with the customer requirements of having an easily movable equipment, an ESAB power source with a water-cooled welding head PRB 33-90 were chosen. Productivity data The pre-programmed parameters can easily be recalled from the memory of the power source. Compared with the soldering which was the process earlier used, the threshold in making a joint has lowered significantly. To solder a joint took almost 30 min to complete and one could never be quite sure of the finished quality. With Orbital TIG welding the arc time is approximately 1 minute on a Ø60 mm pipe and the quality can easily be controlled. Welded cunifer pipe. Diameter 60 mm and wall thickness 3.0 mm Advantages Improved weld quality and reduced work time. More safe open flame when soldering inside a shiphull is always a safety hazard TIG arc was welcomed by the shipyard fire-squad. Easy to operate. More welders are now able to make high quality weldments. The shipyard has welders from different nations the programming menu can be changed to different languages just by pressing some buttons.
CASE STORY contribution by Derek Harvey, ESAB UK Cladding valves for the offshore market Description The offshore market is very demanding in the cladding area and ESAB equipment was chosen due to its easy use and compactness. Quality and reliability were also important, as well as accurate control over all welding parameters. The welding head is mounted on a small column and boom, and the workpiece on a turntable, driven by the VEC motor, which is controlled by the power source. Our customer manufactures his own hot wire system, which is connected to the wire at the outlet nozzle. A number of systems have been supplied to date and are performing well in production. Contents ESAB power source A25 welding head with AVC, weave and wire feed VEC motor for rotating a turntable A6 manual slide for coarse position the welding head in X and Y plains Advantages Easy to use and compact Quality and reliability Accurate control over all welding parameters A25
CASE STORY contribution by
CASE STORY contribution by