How Dosing Pumps Tube Connection Kits Work

Most chemical dosing pumps, whether they are Solenoid, Motor-driven or Stepper motor pump, require tube connection kits for installation into the process.

The Tube Connection Kit

The tube connection kit is a set of precision components designed for the effective fastening of the dosing tube onto the various valve fittings of a chemical metering pump.


Tube connection kits are fabricated from either PVDF or PP, with a holding ring (PVDF, PP or SS) and matching PVDF or PP Pipe Holder. It is critical that the tube end is cut perpendicular to the tube length, with no burrs or split ends. We recommended the use of a tube-cutting tool to ensure that a clean cut is made.

Delivery Tube Fittings Diagram
Delivery Tube Fittings

Suction Tube Fittings Diagram
Suction Tube Fittings

As shown above, place the Threading Nut over the tube, then the Holding Ring, and finally the Pipe Holder should be pushed into the tube end. 

Ensure that the sealing O-Ring is correctly in place on the threaded valve assembly.

Hand-tighten the Threading Nut onto the valve and screw down tightly.  This will push the pipe holder into the end of the tube, spreading it up into and against the holding ring. Undo the nut, check the fittings are secure and do the nut back up until hand tight.


The O-ring will prevent any chemical leak. Please also check that there is a small gap between the base of the cone and the holding ring as if they are butted up against each other, you have tightened the nut excessively.   For PVDF tubing, you may need to heat up the tube with a brief open flame to assist in fitting on the cone.  With PE tubing, hot water will suffice.

A selection of Tube Connection Kits are available from Convergent Water Controls. We can supply both metric & imperial tubing sizes up to 9x12mm for 3/8”, ½” & ¾” BSP male threaded valves.   

CWC Sales Freecall: 1800 137 954 or email at


While you're here...

Subscribe Now to get the latest info on our new products and systems.

Scroll To Top