Steel Tubes – OD vs ID

Whilst at face value this seems like a set of circumstances you’d think were all but impossible to exist, there is an ongoing controversy in the worldwide market for ERW tubes. The controversy is around the debate about how accurate measurements are for the diameter of tube supplied. At face value it would be fair to think that this problem seems impossible to be in place, as surely they are a universal constant. The problem comes from not the measurements themselves as such, but rather the way in which they are taken.

Steel Tubes are usually sold in accordance with the diameter. Where the problem comes in is which of the two is used. Some suppliers provide the outer diameter (OD) of the tube, whilst others consider the inner diameter (ID) to be the correct one to use. In terms of what difference this makes, the thickness of the wall of the tube could make it too big or too small for placement. It could also be the case that someone taking an OD measurement to be the ID might find the inner size of the tube is not correct for their requirements.

If the way in which ERW steel tubes were measured was standardised it would mean that this problem ceased to exist. The fact of the matter is that it is impossible to implement this type of standardization as there are cases where the OD is required rather than the ID, and of course vice versa. Due to this it is imperative that the exact requirements and specifications are made clear by both the purchaser and the supplier.

Our approach has always been to ensure clarity is in place with respect to OD and ID measurements. An important part of the world class service we provide in the delivery of ERW steel tubes is ensuring that your requirements are met with the highest level of accuracy possible. We work with very low tolerance levels, meaning that whether your requirement is the OD or ID measurement, we are the people you can trust to deliver what you need.