LVHV (Welding Torch On-Tool Extraction) Test Kit/Adaptor

Description

NEW Updated MkIII Kit

The kit contains two stainless steel welding torch adaptor tubes – 48mm ID and 42mm ID to accommodate different welding torch head sizes.

The MKIII kit now also includes a reducer/shut off valve for each of the tubes (above).

These valves have been precision milled to attach as a snug fit over the end of the tube.  Testers can now reduce the flow into the pipe to check that the LEV system alarm does activate (as HSE recommends) at extract hose velocities below 20m/s.

Aaah?  But the welding hose may be a different diameter internally to the attachment stainless tube.  How then to work out what velocity pressure from the Pitot in the tube test hole will give exactly 20m/s in the torch hose?

A Menu option on the latest version of the OXYL8 App (still free and available from your App store ….. simply search using “OXYL8”) will do these calculations for you. 🙂  Note this updated version of the App will be available from about end Apr 25.

Kit comes complete with carry case.

How to Use?

Having connected the welding torch head to the Stainless tube using the included silicone hose adaptor (and wing Jubilee clips) – then insert a 305mm Pitot (we prefer the TSI version – TSI Pitots) through the 10mm Test Point pre-drilled at one end of each tube and align with the airflow in the centreline of the tube.

Take the Velocity Pressure and convert to a velocity.

Divide the Velocity by 1.2 to get a reasonable average of the velocity in the stainless test tube.

The labels on the Stainless tubes give the internal diameters and Areas (already worked out).

To assess the Flowrates (Q) going through the LVHV extractor heads – simply multiply the stated label area by the velocity you measured in the tube.  Answer will be in m3/s.

You can also obtain a “reference” Static Pressure at this point.

 

Ideal for undertaking quantitative TExT examinations at “on-tool” Welding Torch fume extraction heads (LVHV).

The kit meets HSE requirements as set out in their FAQ section of their website.  See this link (third bottom button on page) for details of HSE’s views on LVHV testing http://www.hse.gov.uk/lev/faqs.htm

 

HSE Guidance: – “A Pitot static tube – This can be used in conjunction with a ‘test piece’ of smooth walled duct or pipe attached to the extraction unit inlet.

Pre-drill a small hole into this test piece. Locate the Pitot static tube through this hole ensuring that it sits in the centre of the ducting.

It should sit at least 7 times the diameter away from the opening not attached to the extraction inlet (eg 350 mm for a 50mm diameter duct). This allows the airflow to develop and provide more accurate/stable readings.

The air velocity in circular ducts is not uniform, the centreline velocity is typically 1.2 times the average velocity. Simply divide the centreline velocity by 1.2 to give an estimate of the average velocity.”

 

NEWS

For any customer with a MkI or MkII LVHV Kit – we are now able to offer the 2 x milled valves as an upgrade kit (simply select that option from the order Menu)