Hydro-Milling Services - FourQuest Energy

Hydro-milling, also known as retro-jetting or hydro-jetting, is an efficient method of cleaning industrial piping through the implementation of high pressure water nozzles and jets.

Newly installed process piping typically contains exuberant amounts of foreign debris. These residual deposits can potentially compromise system reliability and lead to premature system degradation and catastrophic failure during plant operation. In order to help preserve the long-term integrity of these process piping systems, hydro-milling can be used to remove all undesirable foreign contaminants and particulate matter. Hydro-milling has been proven as an effective means of removing both large and fine debris from piping surfaces, including post-construction debris, byproducts that result during fabrication, and operation-derived deposits, which are comprised of welding slag, mill-scale, loose rust, and mineral sediment.

The Hydro-Milling Process

During the hydromilling process, water is pumped at high pressure through a self-propelled high pressure nozzle engineered for pipe wall cleaning at service pressures between between 5,000 psi to 40,000 psi (~35500 kPa to 83000 kPa). The attached hose is then sent through a bi-directional feeder and rotated at operator-controlled rates into the piping. The rotational motion of the hose allows the nozzle to easily negotiate 90° elbows, piping turns, and directional changes, in addition to providing full surface area cleaning throughout the entire pipe circumference. Complex vertical and horizontal lengths of pipe with diameters between 2” to 30” are easily traversed with full cleaning capacity. Simple horizontal straight-length pipelines with diameters exceeding 30” can also be cleaned sufficiently. Hydromilling has the capability of providing a 1250 ft. horizontal and/or 350 ft. vertical cleaning spread. All loose debris is efficiently driven out of the system through the intelligent operation of the built-in rear jets. By withdrawing the high pressure nozzle during operation, all debris is pushed out of the line in a predictable and controlled manner. When equipped with auxiliary heating, hydromilling can also be performed in subzero conditions.

As guidelines change to meet more demanding environmental regulations, FourQuest is dedicated to providing services that adhere to all client protocols. In cases where stringent environmental and waste disposal regulations call for reduced water usage, FourQuest Energy’s hydro-milling setup can be outfitted with supplementary filtration skids to recycle all waste effluent. In situations where clean water cannot obtained, external demineralized water and reverse-osmosis skids can be sourced.

FourQuest Energy is strongly committed to providing its services in the safest manner possible, with minimal impact to the environment, our employees, contractors, clients, and the general public. Meticulous planning and engineering goes into each hydro-milling assignment, and an emergency shutdown switch is available to our trained professionals throughout the operation. Furthermore, anti-withdrawal, pressure discharge, and restraining devices are installed to control and mitigate all hazards.

When compared to more traditional water flushes, hydro-milling can match or exceed cleanliness specifications while reducing the time and costs associated with water, waste disposal, scheduling, and equipment requirements.

The Hydro-Milling Process


  • Reduced commissioning (i.e. steam blows) durations on boiler feed water and steam systems
  • High degree of cleanliness on non-critical and critical systems.
  • Can be completed in a variety of conditions, including subzero climates
  • Removes both fine and large particles
  • Lower water requirements compared to conventional water flushes
  • Water recycling capability with minimal waste disposal requirements
  • Reduced costs associated with time and scheduling
  • Boiler feed water
  • Steam systems
  • Water systems