Under pressure operations - below 7 bar

We can provide flowstopping 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 flowstopping capability includes the following:

  • Low Pressure bagging off on both metallic and PE mains, typically up to 75mbar, 630mm diameter PE and 36” metallic.
  • 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 flowstopping up to 7bar and 48”diameter, using ShortStopp II,  TDW 1220, Ipsco Large diameter folding stopple.
  • PE Stopple for medium pressure, 250mm – 355mm diameter. 

Some of our innovative flow stopping techniques offer additional benefits to the customer such as:

  • reduced excavation sizes which reduces 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.
3D laser scanner

PMC have trained P11 inspectors that are now utilising the handheld 3D laser scanner for pipeline inspections.

The 3D laser scanner provides improved accuracy and quicker turnaround times for inspections compared to the traditional method.

A typical general corrosion inspection can be reduced from 1 hour to around 5 minutes. 

Benefits of use

  • Reduced repairs due to accuracy of data
  • Reduction in site labour
  • Faster restoration of pipeline operating conditions. 
  • Accurate and fast asset data collection

Use

  • Pipeline corrosion or mechanical defects
  • Complex shapes
  • Hard to reach areas
  • Fully weatherproof

Our customer says:

“The 3D scanner for P11 inspection is a fantastic piece of kit, providing highly detailed reports in real time whilst reducing time on site, overall cost and potential risk to the asset ultimately allowing the pipeline to be repaired in a timely manner. I will continue to use this kit for any future inspections within Cadent Gas East Midland Pipelines.”

 

Aerial survey

PMC operates a fleet of helicopters along with a crew of pilots to plan and deliver the schedule of surveys. Pipelines are patrolled at 185 km/h and 500 feet.

In 2016, our team detected over 600 potential threats to the pipeline.

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.

Bolting and flanging

With our highly qualified and experienced field technicians, we can offer a broad range of-end to-end mechanical services including bolting and flanging for various pressure ratings and diameters.  Our technicians are equipped with the latest torque tightening and flange spreading equipment to suit your needs.  

Where applicable, certification is issued.

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.

Download a case study of how bond and bolt can be utilised here.

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.

End Prepping

For any joint to be welded every weld set up has to have a design, a bevel angle and a route gap and a route face/landing edge.

Prior to the end prepping process we check the pipe for laminations, discontinuities and we conduct a magnetic particle inspection (MPI) to ensure that the material is of good quality.

We follow welding procedures which gives us the bevel angle, root gap and root face (landing edge). The end prepping process can now begin.

Non destructive testing

PMC uses the full suite of NDT methods to inspect the integrity of the pipe. These include magnetic particle inspection, dye penetration, x-ray and phased array. 

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.

Pressure testing

PMC offer pneumatic and hydrostatic pressure testing services. 

We pressure test PE and metallic pipelines up to pressures of 7 bar and diameters of 630mm.

From supplying the water to drying of the pipeline, we offer the complete end to end service.

We now have gauges that can be monitored remotely via an app.

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.

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

Pipe fitting

Following specified design, we fit sizes ranging from 3/4 inch to as large as the customer requires. We use varying techniques dependent on the type of pipe and this would include any transition fittings. 

We can also install "set on" fittings and "set in" fittings.

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. 

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.

Large diameter main lay

PMC are accredited under EUSR to lay short length large diameter pipe up to 800mm. This applies to both emergency and planned works. We carry the stock and equipment for emergency use.

Visual asset surveys

With our diverse range of skill sets, we are able to offer various types of visual surveys ranging from asset data collection, categorisation of pipework and asset condition (i.e VS02), valve survey and investigation work.  All surveys are tailored to the customers’ requirements and offer valuable information to the asset owner.

We carry out a full line walking service, reporting any defects and remediating all raised defects with 28 days. This includes taking depth measurements to ensure the correct depth coverage of the pipeline. 

The posts we install include Aerial Marker posts (AMP), M4's and Cathodic Protection posts (CP). We have the capability to carry out CP repairs.