Under pressure operations - above 7 bar

PMC provide a range of activities which can be utilised under pressure.

We offer a complete flowstopping service for planned and emergency operations on a full range of diameters and materials across all pressure ranges (LDN, LTS, NTS).

These include steel, cast and ductile iron and PE systems at all pressure ranges up to 100 Bar on pipelines up to 48” diameter.

We utilise various stopple techniques such as:

  • PE squeeze off;
  • IRIS stop;
  • Bag off technology;
  • Fixed head stopple;
  • Bifurcated stopple;
  • Bond and Bolt.

We also undertake under-pressure drilling for all diameters and material limits up to 100 Bar and 48” diameter.

Services

Stopple Operations

PMC provide a complete flowstopping service for planned and emergency operations on a full range of pressures, diameters and pipeline materials.

These include:

  • Steel, cast and ductile iron and PE systems
  • All pressure ranges up to 100 Bar
  • Pipelines up to 48” diameter

We utilise various stopple techniques such as:

  • Fixed head stopple;
  • Folding head stopple;

We do single, two, or four position Stopples that can be used with bypasses.

Bifurcated Stopples can sometimes be used and these reduce the amount of tees and under pressure drillings needed without interrupting flow.

Hot cutting

Hot cutting is a method we use for cutting pipe by flame or by grinder. We have mobile units equipped with oxypropane. We also utilise mechanically assisted techniques.

Under pressure drilling

We have a wide variety of equipment to undertake top or side offtake under pressure drilling operations from 1" - 48". These can be for, offtake connections up to size on size, stopple operations up to 100 Bar, pressure points and more. 

Bag off

PMC conducts bag off flowstopping activities on both metallic and PE pipes.

We conduct the following bag offs:

Low pressure bagging off 3” - 12” using Wask 312 equipment - this involves drilling and entry into the main and inserting a deflated bag. This is then inflated to achieve a flowstop. 

Low pressure bagging off 14” – 48”  using ALH equipment.

Medium pressure bagging off using IRIS stop equipment - this is for planned flow stop operations on cast iron, ductile iron and steel mains on pipe diameters ranging from 14 inch up to and including 48 inch.

Where required, bypasses can be fitted.

Bond and Bolt

PMC are utilising an innovative technique for bag stop and camera insertion into low pressure metallic mains, coupled with a standard flowstopping bag.

Benefits of use include:
• Reduction in excavation costs due to less depth and size;
• Reduced re-instatement costs;
• Faster process from mobilising to site to flowstopping;
• Reduced occupation time of the highway;
• Potential to avoid ‘deep excavations’ and a 1 year reduction in defect liability.

Below 7 bar flowstop

We can provide flow stopping services for either planned or emergency operations, covering a wide range of pressures, materials and diameters.  We can also advise on the most suitable technique for the customers’ requirements. 

PMC’s Below 7bar Flow Stopping capability include the following;

Low Pressure bagging off on both metallic and PE mains, typically up to 75mbar, 630mm diameter PE and 36” metallic.

Medium pressure bagging off using IRIS stop equipment - this is for planned flow stop operations on cast iron, ductile iron and steel mains on pipe diameters ranging from 14 inch up to and including 48 inch.

Medium Pressure flowstopping using the Shortstop 60 on metallic mains.

MDPE Squeeze off operations up to 500mm PE for both Low Pressure and Medium Pressure.

PE100 Squeeze off operations on Durapipe and Profuse.

HDPE (7bar) squeeze off operations 180mm to 315mm.

Metallic Flow Stopping up to 7bar and 48”diameter, using ShortStopp II, TDW 1220, Ipsco large diameter folding stopple.

PE Stopple using the TDW short stop II for medium pressure, 250mm – 355mm diameter. 

Some of our innovative flow stopping techniques offer additional benefits to the customer such as; reduced excavation sizes, thus reducing the amount of excavated and waste material, reduced amount of backfill required, smaller excavation foot print which minimises the effect on any working space restrictions such as street works and safer working conditions for operatives working in shallower excavations.

PE Drilling/Branch Saddles

We can provide a range of services for operations on Polyethylene pipes, including High Density Polyethylene (HDPE) operating at pressures up to 7bar. We stock a range of Polyethylene fittings to suit your needs.

Squeeze Off

We offer squeeze off services up to 7 bar and 500mm. 

We have the capability to conduct squeeze off on various pipe sizes and pressure and have the following equipment:

SOU250 hydraulic squeeze off unit for 180 - 250mm;

SOU400 hydraulic squeeze off unit 250 - 400mm; and 

SOU500 hydraulic squeeze off unit 315 - 500mm

Vacuum saddles

Working in partnership with GPS, we now offer uni saddles and vacuum saddles up to 800mm. They can be used on pressure up to 7 bar on MDPE  and HDPE pipe.

We now offer a greater range of offtake sizes, from 80mm to 250mm.