This kit contains a stainless steel tube (with 10mm Test Point drilled at one end), rubber hose adaptor and misc Jubilee clips for undertaking quantitative TExT examinations at on-tool Welding Torch fume extraction units (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.”
In line with HSE’s advice the principle of of operation of this LEVShop On-Torch adaptor kit is that the rubber adaptor is connected to the 500mm stainless steel extension tube and the other end of the hose is attached to the welding torch (being careful not to block the air extract holes) and tightened down using the winglock jubilee clips.
A small Pitot tube (not included but see TSI 305mm Pitot Tube) can then be used to obtain a representative flowrate and static pressure at the LVHV head.
Further hose clips are included to permit connection of the steel adaptor to larger bore LVHV heads (requires additional piece of rubber sheet to form a tube for larger diameter heads – which can be supplied on request).
Kit comes complete with carry case.