A useful jetter nozzle directs the flow your machine supplies into the pattern the job needs. Pressure, flow, internal passages, orifice geometry and jet angles work together. Understanding those relationships helps explain why two different nozzle designs can serve different stages of the same job.
GPM and pressure work together
Flow is the volume of water delivered over time. Pressure is related to the energy available to drive that water through the orifices. Hose losses mean pressure at the nozzle can differ from the reading at the machine. The pump, regulation system, hose and nozzle configuration all matter; changing an orifice does not create additional pump power.
A configuration must match the operating setup and remain within equipment ratings. Increasing pressure alone does not ensure debris is transported out of the line. Enough water, an appropriate jet pattern and a route for the returning material are all needed.
Rear jets provide thrust and cleaning
Water directed toward the rear produces a reaction force that helps move the nozzle forward. For a given jet force, a rear jet closer to the pipe axis directs more of that force along the pipe. Angling it farther toward the wall changes the balance between axial thrust and wall coverage. State the angle convention before comparing numbers.
KEG’s Traction family uses alternating 8° and 12° rear jets for a tight cleaning pattern and pulling. Its Cleaning family uses alternating 15° and 25° rear jets for everyday cleaning. Those are specific design choices, not a rule that one angle is best for every line.
Forward and rotating jets serve different purposes
A forward jet can help establish a route through an obstruction. Water allocated forward is part of the nozzle’s total flow budget. Rotating jets sweep a pattern across the pipe wall. Penetration, rotation and cutting are different capabilities: an ordinary Rotor finishing nozzle should not be treated as a purpose-built root cutter.
What nozzle efficiency means
Internal passages and the transition into each orifice affect turbulence and jet quality. KEG identifies selected families, including Cleaning and Traction, as Tier Three and rates them at 80%+ fluid efficiency in SBK-F26. This is a manufacturer’s design rating; it is not a promise of an 80% reduction in water use or an independent NASSCO certification of every product.
See the tier guide for the distinction between design classification and insert material. Some useful KEG nozzles are drilled or Tier Two models.
Connect engineering to job cost
At a constant operating flow, gallons used equal GPM multiplied by water-on minutes. A nozzle that completes comparable work in less operating time can save water and crew time. Measure the finished result, minutes, gallons and service costs together; no single specification proves a guaranteed number of passes or payback period.
Simple ordering: for 1/4-inch and 3/8-inch nozzles, enter the GPM you want to run. For 1/2-inch and larger, provide GPM and working PSI. Select the correct hose connection first; model-specific flow limits and pipe suitability still apply. Find your nozzle.
For a compact truck setup, compare the 1/4-inch Starter Kit and 3/8-inch Essentials Kit. For dedicated propulsion and wall cleaning, consider the 3/8-inch Cleaning + Traction Kit.
Technical basis: KEG SBK-F26 family descriptions and jet-angle specifications. Follow the operating instructions and ratings for the exact machine, hose and nozzle.