Automatic MCL field joint coating system

Automatic MCL field joint coating system

Keywords: PIH, Coatings, Piplines

In February 2000, PIH were awarded a contract to perform field joint coating services on the 300kms x 8"/9"/10" Antamina Concentrates Pipeline Project in Peru.

PIH were sub-contractors to Consorcio Spie Capag Icegsa, who were building the slurry pipeline system for a local mining group: Compania Minera Antamina SA.

The pipe was externally factory-coated with a three-layer extruded polyethylene system, up to 3mm thick. PIH have been contracted to coat all field joints using their new patented automatic multi-component liquid (MCL)application equipment.

The project emphasised a trend away from low-technology, heat-shrinkable polyethylene sleeves and tapes, towards high performance solvent-free multi-component liquid coatings. These MCL systems claim:

• exceptional performance under high soil stress conditions;

• consistent and immediate verification of installation quality;

• superior levels of adhesion to both steel substrate and factory;

• low repair rates;

• no possibility of air-entrapment;

• versatility – MCL coatings are also applied by PIH for onsite coating of bends, wide-joints, valves, tees and other fittings, horizontal directional drill (HDD) and thrust bore pipe, using the same crew and materials;

• very fast application cycle times (regardless of pipe diameter) using a single crew;

• improved economies, when compared with conventional field joint coating systems.

The equipment spread was designed/manufactured by PIH in-house. Onsite operations were supervised by one (or more) PIH technicians, for each working spread, comprising:

• 1.

  Abrasive blasting equipment.

• 2.

  Sophisticated plural component airless-spray mixing and control equipment,housed in containerised modules, connected to:

• 3.

  Automatic patented PIH field joint coating machines, offering:

• "pre-programmed" application cycle, repeatable from one joint to the next without variation;

• controlled coating bandwidth and thickness;

• excellent safety and environmental performance;

• reduced material usage;

• very fast application (less than one minute per joint) with reduced manpower resources.

The Antamina project represented a major undertaking: the pipeline runs North to South, tracking parallel to the Peruvian coastline, then cuts east inland up into the Andes mountain range, to an altitude of 5,800 metres.

PIH followed closely behind the front-end welders, coating an average of 125 weld joints per day (outputs of around 300 joints per day were achievable),using a 100 per cent solids (solvent-free) MCL anti-corrosion coating. The field joints were said to be touch-dry in a matter of minutes, permitting pipe handling/lower-and-lay activities within hours of application.

Phil Bond, managing director at PIH, commented:

PIH remains dedicated to providing excellence in the field. We actively encourage the development of new technology, to replace old and outdated practices, thereby offering main contractors and operators with superior/low-cost field joint coating solutions for the twenty-first century. This recent move into the mineral slurry pipeline business represents another exciting opportunity for PIH, as we continue to expand our core business activities.

PIH also informs us that, following the award and mobilisation of no fewer than seven major projects in the UK last year; Pipeline Induction Heat Limited(PIH) have provided mainline (front-end) and tie-in units, to coat external pipeline field joints with fusion bonded epoxy powder (FBE). This fully integrates with the FBE factory coating system on the pipes, to provide a seamless anti-corrosion barrier coating system.

The pipelines range in diameter between 12.75in and 48in OD and include:

• Betchworth to Rowhook – BG TRANSCO Entrepose UK Ltd, 25.2kms x 48in OD;

• Teesside to Saltend – BP AMOCO Murphy Pipelines Ltd, 106kms x 12.75in OD;

• Bridge Farm to Birch Heath – BG TRANSCO McLoughlin Group Plc, 20kms x 36in;

• Shome to Famingham – BG TRANSCO Entrepose UK Ltd, 15.5kms x 30in OD;

• Peterstowe to Gilwern – BG TRANSCO NACAP Lawrence JV, 23.5kms x 24in OD;

• Mawdesley to Warrington – BG TRANSCO McAlpine PPS Pipeline Systems JV,31.56kms x 42in OD;

• Drointon to Sutton-on-the Hill – BG TRANSCO Murphy Pipelines Ltd,26.32kms x 48in OD.

Front-end FBE field joint coating operations use PIH's "CAT-COAT"tracked prime-movers, which carry all equipment necessary to perform:

• abrasive grit blasting;

• induction "pre-heating" (to 240°C);

• automatic FBE powder application;

• inspection.

High production is achieved by simultaneously working on three consecutive field joints. The unit then moves forward 12m (or 18m) and the sequences are repeated. PIH's "tracked" CAT-COAT vehicles cater for the wide range of topography and ground conditions which typify rural Britain, allowing production to continue, even in very steep gradient conditions such as those experienced around Monmouth (Wales) on the Peterstowe to Gilwern pipeline spread.