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Utility Week Live
04 Jan 2024

BISEP Line Stopping

  • BISEP Line Stopping
  • BISEP Line Stopping
  • BISEP Line Stopping
BISEP Line Stopping BISEP Line Stopping BISEP Line Stopping

The BISEP® has an extensive track record and provides pioneering double block and bleed line stop isolation. Achieved using patented and DNV Type Approved technology, the BISEP provides a fail-safe isolation while flow is maintained through an integrated bypass. The BISEP offers significant safety advantages over traditional line stop technologies, with the hydraulically activated dual seals providing a tested and monitored isolation of live, pressurised pipelines.


  • Valve replacement / installation
  • IJ replacement
  • Pipeline diversion / re-routing
  • Mid-line repair / pipeline defects
  • Pipeline decommissioning


  • Size 3”– 56”
  • Pressure up to 153 bar
  • Temperature -20°C to 100°C

Key Features

  • 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
  • Dual compression seals provide higher integrity isolation than traditional cup seals
  • Hydraulically activated seals can be manipulated to improve performance when sealing in pipes with issues such as ovality and internal surface irregularities, ie weld seams, corrosion, erosion
  • Monitored dual seal annulus void proves seal integrity before and during intervention work
  • Isolation integrity continuously monitored through seal annulus void
  • Seal annulus void provides a Zero-Energy Zone
  • Pipeline pressure maintains a fail-safe isolation independent of hydraulic activation
  • Hydraulic rotation of the plugging head enables BISEP deployment into pipes in any orientation. Horizontal, vertical and pipes inclined from the horizonal making it more versatile than traditional line stop systems.
  • Ability to perform a reinstatement pressure test against the rear of the plugging head while isolation is maintained
  • Can be deployed through a conventional fitting, equal tee or mechanical clamp
  • 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