TPi January 2017

Welding technology

Weld backing tape for weld purging It is important when welding metals such as stainless steel, titanium and zirconium that the welding zone is purged of oxygen even as low as ten parts per million (ppm) before, during and immediately after welding, in order to achieve a clean, oxide-free, zero- colour weld. Huntingdon Fusion Techniques Weld Backing Tape™ comprises a 75mm (3") wide aluminium adhesive tape backing strip, in the centre of which is a 25mm (1") wide band of woven glass fibre matting.

placed a large order for Weld Backing Tape for immediate delivery. Huntingdon Fusion Techniques – UK

hft@huntingdonfusion.com www.huntingdonfusion.com

Once the tape is positioned with the glass fibre matting under the centre of the weld joint, the welders can start their arc. The welding torch argon flow has plenty of space to move between the pores of the matting, which allows the welding arc to stabilise and start forming the weld root. Measured by a Weld Purge Monitor ® , all contaminating oxygen below 100 parts per million (ppm) is removed and the stainless steel weld root is completed successfully, with the molten metal being cast onto the fibre glass with excellent side wall fusion and under-bead profile. The customer was said to be enthusiastic about the clean, metallurgically sound, non-oxidised weld, and

Gas flow using API sampling probe

During a recent trip to South America, weld purging experts from Huntingdon Fusion Techniques (HFT) were supporting their exclusive distributor and local customers when a discovery was made concerning the use of the company’s Argweld ® Backing Tape™. A customer showed how the use of his former ceramic backing tiles and the tiny space available for the weld root formation prevented adequate argon flow and caused the welding arc to blow back at the welder. Luke Keane, distributor support for HFT, explained, “Ceramic backing tiles are designed for submerged arc welding where oxidation is prevented by powder as opposed to argon, so the customers were using the wrong product for GTAW/TIG welding. A demonstration of Argweld Backing Tape followed, which allowed the argon to flow freely, eliminating the blow back of the arc that was happening previously and enabling the welders to produce a perfect root weld.”

Finished weld

New welding machine for HDPE pipe Delta 1000 Trailer is a self-aligning fusion machine suitable for welding thermoplastic pipes for the transport of water, gas and other fluids under pressure, up to Ø 1,000mm (36" IPS/DIPS). The machine can fuse pipes according to the ISO 21307 High Pressure standard, enhancing productivity and allowing a claimed 60 per cent time saving. device helps remove the heating plate during the welding procedure. An on-board hydraulic electric facer is equipped with a safety microswitch to prevent accidental starts, and a thermal circuit breaker protects the motor. The PTFE-coated hydraulic heating plate is supplied with a high-temperature- proof bag, to prevent the heating element from being scratched.

and pilot the welding cycle in an easy, fast and intuitive way. A data-logging system is included, to store full welding data, downloadable through a USB port straight into PDF files. The Easy Life system has the capability store up to 4,000 joint reports. The Delta 1000 Trailer allows easy welding of fittings such as elbows, tees, Y-branches and stub flanges. Accessories available on request include clamp inserts from Ø 335 to 900mm, a trolley, a tool for flange necks, a kit for in-ditch use, and a hoist. Ritmo SpA – Italy www.ritmo.it

The machine body is mounted on a four-wheeled chassis, with two steering wheels and a safety brake, and is easily removable for working in tight spaces. Steel hydraulic clamping with fast-lock- ing inserts allows placing and removal of inserts in seconds. A self-detaching

The Easy Life control panel, with a large graphic display and GPS traceability, is removable from the machine body to enable welding from outside the ditch. This allows the operator to program

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January 2017 TUBE PRODUCTS INTERNATIONAL