Generally, spiral pipes cannot be stored in large quantities in the production workshops when delivered to the end-users, which necessitates dealers to maintain some inventory. However, dealers typically do not have large indoor warehouses; most of them rely on outdoor storage facilities, where spiral pipes are inevitably exposed to the elements like wind and sun. So, how can we distinguish between floating rust and rust on spiral pipes?
Floating rust, as the name suggests, refers to a layer of rust that sits on top of the spiral pipe and can be easily removed by wiping with a towel or other materials. Simply put, floating rust can be considered as almost non-existent rust and is considered normal.
On the other hand, rust on spiral pipes develops over a prolonged period, usually more than a year, due to continuous exposure to the elements. Rusty spiral pipes exhibit various sizes of pits on their surface, which is a significant difference between floating rust and rust.
Spiral pipes are produced by sawing billets from steel mills, followed by heating in a rotary furnace, piercing, sizing, straightening, cooling, cutting ends, and finally packing into qualified finished products. These pipes are primarily used for transporting oil and natural gas, and their specifications are denoted by outer diameter and wall thickness. Spiral pipes come in both single-sided and double-sided welding varieties, and the welded pipes must meet the requirements for hydraulic pressure testing, tensile strength of welds, and cold bending performance.
