Overview Types Rocvent ventilation tubing is manufactured in a number of styles Layflat T ubing is collapsible PVC tubing positive pressure manufactured in a selection of grades to match the strength specifications required by customer Spiral Ducting spiral reinforced ducting positive and negative pressure DuoDuct is collapsible dual oval chambers reducing required headroom by 25 V ertical Shaft T ubing is a collapsible PVC tubing complete with 2 webbing radio frequency welded to the tubing at opposite sides 180 with connection of each length with 2 2 ratchets connecting the webbing of each length of tubing Call your Rocvent representative for the correct style size and material weight for further information MANUFACTURE The material is welded in purposebuilt radiofrequency machines to form flexible tubes SIZES T ube diameters vary from 300 mm to 2400 mm 12 96 Standard tube length is 762 15m 25 50 T ube sections are available in other lengths to custom order COLOUR T ubing is normally manufactured in highly visible colors T ypical ventilation tube section ROCVENT INC MINE TUNNEL VENTILATION 13 wwwrocventcom