OPW Celebrates 15 Years in the Underground Piping Business

by OPW | Jun 18, 2012

OPW is pleased to be celebrating our 15th anniversary in the underground piping business. A lot has changed in the underground petroleum world, but the fundamentals remain the same. Quality products, made from quality materials, engineered to accommodate the harsh underground conditions and provide long-term performance and value for customers.

Sometimes, however, lessons of the past are forgotten. This is true in every industry, and recycled ideas often lead to problems as people forget the original issues. One thing that remains constant in the underground world of petroleum systems is movement. Everything underground is subject to movement, be it from frost heave, water table fluctuations, line shock, or simple ground and backfill settling. Slabs move in relation to tanks, tanks move in relation to pipes, and pipes move in relation to sumps. In certain conditions, the movement can be dramatic and potentially destructive if the system is not properly designed for it. Swing joints and flex-connectors were introduced to help relieve the stresses that adversely affected rigid piping systems. The advent of flexible pipe largely eliminated the need for these stress relievers. Flexible entry fittings were also introduced as a means to prevent the pipe shear caused by underground movement.

Fast forward to today. You rarely hear of a pipe or sump breaking at an entry any more as flexible boots have accommodated for the movement. Despite the vast improvements over the years in flex boot materials that have tremendously extended their useful life, the fact remains that some early generation flex boots offered by some suppliers are not lasting the life of the station. This has served to revive the idea of a rigid entry fitting. Some manufacturers would have you weld or glue the pipe to a sump wall. Aside from the serious installation challenges this installation method and these products present in real world conditions (weather, dirt, moisture, temperature, contamination, special tools and procedures, training….), it is really just counterintuitive to rigidly attach two objects together that are guaranteed to move independently of each other! A failure or installation issue inevitably results in an expensive dig up.

That’s where the new Rigid Entry Fitting (“REF”) from OPW comes in. Imagine a Rigid Entry Fitting... with no exposed rubber... that still accommodates the inevitable ground movement. And it requires no surface scraping/grinding, dry fitting, chemical cleaners, glue, caulk, special machines, or a 10 step installation procedure and video.

The new “REF” Rigid Entry Fitting from OPW:


  • Provides Massive Sealing Forces and Sealing Redundancy Throughout – Maximum containment and unmatched protection from water intrusion
  • Preserves total accessibility – For monitoring, maintenance, testing and repair
  • Maintains flexibility to accommodate pipe and ground movement
  • Provides unmatched durability at dispenser sump entries to withstand the rigors of repeated line shock associated with high volume stations
  • Incorporates a Hard Shell Exterior – To weather the elements and abuse of the underground environment
  • Allows easy installation – In all conditions with no complicated preparation, intense training, or special machines and tools.


Quality products, made from quality materials, engineered to accommodate the harsh underground conditions and provide long-term performance and value for our customers. At OPW, this philosophy has protected our customers for 15 years, and will continue to serve them well in the future. Happy Anniversary indeed!

OPW is the global leader in dispensing products, environmental systems, secondarily contained fuel delivery systems, fuel management systems and clean energy fueling products, including dispensing nozzles for vapor recovery, gasoline, diesel, LPG, Hydrogen and CNG; swivels, breakaways, valves and fittings; underground and above ground storage tank equipment, spill containers, overfill prevention devices, secondary containment sumps and flexible piping; tank gauging equipment and automated fuel management systems.  OPW is part of the Dover Energy Segment of Dover Corporation (NYSE: DOV).