When designing a tank liner, obviously our layout engineer needs to be using the same terminology or definitions that you use to describe the tank. In particular there can be some misleading terms used to describe the top rim or flange of the tank.
We use the phrase “angle rim” to describe a rim that comes straight out from the tank wall and ends. Typically an angle rim is a piece of angle iron that has been welded to the tank. We make the liner to come out across the width of the angle iron and then fold back underneath where the Wittclip™ fastens to the liner.
A “channel rim” is a rim that goes out and then back down. In this case the liner would go out across the top of the rim and then turn down 90o and stop at the end of the channel where the Wittclip would be placed.
A “tube rim” is a rim that goes out, down, and then returns back to the wall of the tank. If the width of the tube is under 2 in. we can use a wide mouth Wittclip. Otherwise the liner would need to be mechanically fastened with a compression strip or other type of fastener.
Tanks with no rims we would describe the rim of the liner as “straight back down”. The liner would be creased to accommodate the thickness of the tank and then extend down the outside 2 to 3 inches. A clothespin style Wittclip can be used on these types of rims.
Tank drawings don’t always show the exact type of flange and we can always provide a sign off drawing prior to fabrication. We also have a downloadable quote form that has a section for the type of rim on your tank.