• 3" – 56”Pipelines

  • -20°C – 100°CTemperatures

  • Ambient to 2220 psiPressure Range

  • DNV TypeApproval

BISEP Pioneering Line Stopping Technology

Leak-Tight Double Block & Bleed Isolation

The BISEP is the market leading technology solution for hot tap installed line stopping, providing double block and bleed isolation while maintaining pipeline flow through an integrated bypass.

BISEP 30in Kinder Morgan New Mexico Placitas

Avoid Outages and Maintain Production during Line Stopping Activities

STATS BISEP® is the industry-leading DNV Type Approved line stopping technology.

Fail-safe hydraulically activated dual elastomer seals provide tested, proven and fully monitored leak-tight isolation of pressurized pipelines, suitable for use in hydrocarbons, high pressure liquid CO2 and Hydrogen.

Importantly, self-energization of seals maintains isolation integrity independent of the hydraulic activation.

See BISEP in action in one of our case studies below.

BISEP DS integrated bypass Cadent, UK

It [BISEP®] brings considerable benefits in terms of the size of the excavation, the number of interactions with the pipeline and all the other risks associated with working on an existing pipeline...With BISEP we've been able to reduce the risks and we're delighted to be where we are.

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Marcus McFarlane

Project Lead

Mutual Energy

  • 3" – 56"Pipelines

  • -20°C – 100°CTemperatures

  • Ambient to 2220 psiPressure Range

  • DNV TypeApproval


Line Stop Technology

Product Information

BISEP Line Stopping

BISEP® offers significant safety advantages over traditional line stop technologies, with the hydraulically activated dual seals providing leak-tight isolation of live, pressurized pipelines.


  • Pipeline launcher valve installation / replacement
  • Pipeline repair, replacement, or decommissioning
  • Pipeline / pipework re-routing
  • Mid-line repair of pipeline defects
  • Isolating pressure vessels
  • Isolation of pipeline end manifolds, pipeline end terminals for repair, upgrade, or replacement

Multiple BISEPs® can be used to provide mid-line isolation of pipeline sections, and the introduction of a bypass line allows sectional isolation to take place without the need to shut down your entire system – or affect product flow.

The BISEP® is designed to resist backpressure and therefore can also be used as a test boundary for pipeline reinstatement testing. 

Uniquely the BISEP® is designed to take 50% of its design pressure in the reverse direction. This allows pressure higher than the isolated pipeline pressure to be applied to the reinstated pipework (as a pressure test or purge) prior to removing the BISEP®.

STATS also supply split tee fittings or mechanical tie-in clamps for hot tap and line stop applications along with its patented dual seal slab valves and SureTap hot tap machines.

To allow the BISEP® and valve to be recovered a completion plug and blind flange can be provided to isolate the fitting branch off-take.

  • 3" – 56"Pipelines

  • -20°C – 100°CTemperatures

  • Ambient to 1479 psiPressure Range

  • DNV TypeApproval

Reduced Cost

Shorter Timescales

Product Information

BISEP with Integrated Bypass

BISEP® can be configured with an integrated bypass through the launcher, ideally suited to lower pressure applications.

Additional Benefits

  • The BISEP® launcher (housing) includes an integrated bypass which maintains production once the isolation is activated, resulting in no loss of production.
  • Double block and bleed isolation through a single fitting with integrated bypass requires fewer fittings and significantly reduces costs and project timescales.
  • Pipeline pressure maintains a fail-safe isolation independent of hydraulic activation.
  • The BISEP® is installed into the pipeline unset allowing deployment into a flowing pipeline, resulting in no interruption to production and saving time on site.
Engineering Working On BISEP Equipment

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