Air Pressure in a cleaning system with Y-joint Setup

The University of South-eastern Norway (USN) has on behalf of Navadan been testing our PVC hoses and air loss in a Y-joint Setup.


When a product, or solution, has been offered to customers for years, the functionality of the components can be taken for granted; trusting that “if it works, don’t fix it!”. Although our PVC hoses are of high quality standard, it is beneficial to us and our customers to understand both the effect of the setup on air pressure loss and the PVC hose itself. Eventually, we can answer to whether there will be a need for improvement in future product development of this setup.

During recent months, The University of South-eastern Norway (USN) has on behalf of Navadan been testing our PVC hoses, and it all started with one simple research questions:

“How much pressure does our PVC air hose loose after a total of 40m and a Y-joint?”

This type of PVC hoses (and setup) are included in NAVADAN Bulk Cleaning Kit. No.1;
a Cargo Hold cleaning system for spraying cleaning chemicals to large heights.


The following two sections will briefly demonstrate how the research and tests were performed:


Air Pressure Loss

The research started with a theoretical exercise, calculating the loss in pressure using an industry standard indicator of roughness of high-quality PVC which is 0.25.

Using the formula for pressure loss due to friction:

the pressure loss due to friction was calculated, with a degree of uncertainty, to be 0.019 bar over 40m.

Next was measuring the roughness of our PVC hoses to determine whether the actual loss deviated from the above calculated loss of 0.019 bar.


Absolute Roughness of hose

There are different methods to determine the roughness of a hose.

The chosen method was to use a microscope (x20 enlargement) to measure the maximums and minimums of local heights of the inside of the hose and calculate the average bumpiness.

Based on the formula for tip height for irregularity:

The roughness was measured to be 0.16; a significantly lower value than the previously used standard value of 0.25.

However, it had very little impact on the conclusion, i.e. whether it loss of pressure deviated from the given 0.019 bar.



In a NAVADAN cleaning system, with a setup of 40 m(total) PVC hose and a Y-joint,

the loss of air pressure, with an absolute roughness of 0.16 is 0.018 bar.

After performing these tests, we can assure our customers that:

  1. Pressure loss due to a Y-joint is very limited with current setup
  2. pressure loss due to length of the hose is very limited
  3. the quality of our hoses will allow for even further flexibility of the cleaning system.

This kind of documented knowledge is a clear advantage when answering technical questions from customers related to the focal setup, and for future development of state-of-the-art cleaning and maintenance solutions.



Research and tests were carried out by Mr. Paw Gundersen, Mechanical Design Engineering, University of South-Eastern Norway (USN).