Originally Posted by
mudski
The pipe you speak of is different to what is sold for exhaust and also, applications such as this. The pipe is made at 102mm or 4inch OD. In the exhaust industry anyway, I sell mild steel, aluminised and stainless steel daily. All have 1.6mm wall thickness. We, at work, at one stage decided to import from another, ahem asian company, we got samples first and their pipe was marked as 4inch, or 102mm. But was actually 100mm. The issue there was no expanded couplers, joiners, elbows, flex joins anything we had in our stock which is made to correct specs in 4inch would be a correct fit. Let alone the quality of steel work horrendous.
So. With all silicone tubing, which we make, import, sell and export ourselves to most resellers you see online and in stores, its all made to the exact specs. 4inch ID or 102mm.