Double Block and Bleed Test / Isolation Plug

Positively Isolate Explosive Vapors From Hot Work Areas When Performing Modifications and Repairs


Now available in a three port design!

  • 3/4" to 24" Pipe Sizes
  • Schedule 40, 80 and STD

The Double Block & Bleed (DBB) Plug revolutionizes isolation and testing of pipe connections. The DBB Plug allows an operator to positively isolate and monitor potentially explosive vapors during “hot work”, then effectively hydrotest the new weld connection with one easy to use tool. The dual cavity port design allows water to be introduced to the section between the seals through the fill port while air is simultaneously evacuated through the vent port - creating an air-free barrier between the hot work and residual upstream gases. 

The Aluminum/Steel construction makes the tool highly portable, and easy to position. The volume of water required for a test is so small that testing can be accomplished using a hand pump. This greatly facilitates testing in remote areas of the facility.

A major California Refinery found that one man can easily handle a 10” Plug.

Features & Benefits

  • Aluminum/Steel Construction: Plug is portable and easy to position.
  • 1.5:1 Safety Factor: Minimum.
  • Reduces NDE.
  • Low Water Requirements: Uses less than a gallon of water, reducing waste/treatment expense.
  • Quality Assurance System: Manufactured under a Quality Assurance Program certified to ISO 9001 and several U.S. nuclear undustry standards including ANSI N45.2, NQA-11, 10CFR 50 Appendix B, and 10CFR 21.

How it Works

After determining pipe and schedule size:

  • Install DBB upstream of "hot work" Area.
  • Expand Seals by tightening compression nut(s).
  • Inject inert gas or water between seals (Isolation Zone) and pressurize.
  • Monitor isolation zone and upstream pressure during "hot work".
  • After Weld cools release pressure and seal, reposition isolation zone over weld area.
  • Pressurize isolation zone (up to 2,250 psi (155.1Bar).

Your Choice

  • Buy It.
  • Rent It.
  • Or use our EST Services to provide.
    • installation & testing services.
    • We’re ready to work with you. 
Double Block and Bleed Test / Isolation Plug
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