Main Steam Line Plugs

We have developed three generations of our Main Steam Line Plugs. We were the first to design and supply MSL Plugs capable of withstanding full LLRT pressures that allowed full testing "in the direction of flow".

Remotely Installable From Refueling Bridge
Dual Plug I/R Tool And Two MSL Plugs Weigh Approximately 1000 pounds
Unique Design Permits Testing Of MSIV In The Direction Of Steam Flow
Hydraulically Actuated / Mechanically Locked Holding And Sealing Mechanism
Isolation Of Each MSIV During LLRT Provides Dependability
Redundant, Yet Diverse Means Of Sealing
Readily Installable — Each Plug Takes 45 Minutes Or Less
Mechanical Training Mockups Are Available For Realistic Training In A Non-Radiation Environment

Preferred Engineering developed three generations of our Main Steam Line Plugs. We were the first to design and supply MSL Plugs capable of withstanding full LLRT pressures that allowed full testing "in the direction of flow". We also holds a patent on the design of a hydraulic MSL Plug for larger BWR plants. In 1994, Preferred Engineering developed a third generation MSL Plug for "Wet-Lift" installations. These Plugs are installed in pairs and can be installed using a rigid pole system or lift slings.