High Pressure Pipe Plugs & Stoppers

High Pressure Pipe Plugs eliminate the need to weld on end caps or plates for system testing, saving valuable time. All pipe plugs are designed for simple and safe installation. Steel grips inside of the pipe expand and grip when a nut is tightened, and the elastomer seal ring compresses to form a tight seal for testing.

High-pressure pipe plugs are mechanical devices used to seal or plug the ends of a pipe to facilitate hydrostatic testing and pressure barrier isolation. These plugs are designed to withstand excessively high pressures in such a way that the plugged ends are capable of staying in place with integral restraint while the pipe section under consideration is pressurized.

High-pressure pipe test plugs series of pipe plugs available from Mechanical Research & Design are available for applications that range from 100 psig to several thousand psig. Our custom sizes include ½ inch to 60 inch and larger; sealing can be performed either internally or externally for a given pipe type and pressure.

What Are High-Pressure Plugs Used For?

Hydrostatic testing is essential in numerous industries to ensure safe and effective operation of pressure vessels such as pipelines, gas cylinders, boilers, nuclear process lines, and fuel tanks. The test is used to check these vessels for failures such as cracks, leaks, and welding defects.

During this process, the ends of the pipeline are plugged, filled with liquid, and pressurized to a predetermined test pressure. Traditionally, pipe ends without flanges would be sealed off using temporarily welded flanges or pipe caps which would then be removed after testing.

With the advent of pipe plugs, hydrostatic testing can be performed by inserting these components into the pipe ends to act as a sealing mechanism. The central shaft of the high-pressure seal consists of an energizing nut which, when tightened, expands the steel grips, causing the flexible elastomer seal to compress and form a positive seal between the plug and the pipe’s inner walls. The test cavity created between the two high-pressure plugs is filled with test liquid via the thru test ports, which also allows for subsequent draining after testing.  Air vent ports are typically included on plugs for venting trapped gas to create less volatile testing environments.

High-pressure pipe plugs are essential for all industries that perform hydrostatic testing to verify the integrity of equipment tasked with the responsibility of transporting liquids. Some sectors that regularly make use of high-pressure plugs include the oil and gas, water/wastewater treatment, power generation, and food and beverage industries.

High-pressure pipe plugs are also frequently utilized to provide isolation, that is providing a work-safe pressure barrier for workers, in regions of critical infrastructure failure.  Pipe plugs are typically employed in regions of “hot-work” pipeline repairs to hold back explosive vapors and gas, regions where uncontrolled flow exist, and temporary to long-term pressure barriers (i.e. adaptable to install flow control pressure fittings).

Features and Benefits

One of the significant benefits of using high-pressure plugs is the reduction of material and labor associated with conventional welded pipe sealing methods. This ultimately results in substantial reductions in time and overall costs. Other beneficial features of our high-pressure plugs and stoppers include:

  • Ability to test different types of pipe and tubing
  • Reverse pressure (RP) stoppers allow you to isolate and test the integrity of a single weld
  • Thru Test Port provides testing/draining through the plug
  • Standard sizes are available in different configurations to suit your specific application
  • Capable of testing pipes with operating pressures from 100 psig thru over 5000 psig in many instances
  • Quick and easy testing and isolation of plain-end pipe systems as well as an adapting interface for customer provided pressure and flow control equipment
  • Many models are available with dual seals which enables the user to test sealing efficacy in critical applications

Learn More From Mechanical Research & Design

At Mechanical Research & Design, we provide high-pressure sealing solutions for all your application specific hydrostatic testing needs. Our technical staff is eager to help determine the most feasible plug for your project. For non-standard sizes, configurations, and applications, our in-house engineering and design team will work closely with you to develop the best custom plugging solution. We also specialize in quick turn-around design and fabrication for your urgent needs!

If you would like to learn more about our high-pressure plugs or any of our other products and services, feel free to contact us or request a quote.

Translate »