This is easily explained, since the Russian metric system is based on the outer diameter (for steel welded tubes), or the equivalent diameter (for water and gas steel pipes), while the system operates inch inner diameter. Ie a 'pipe-inch' – it's the outer diameter of the pipe inner diameter which is about one inch ordinary. Accordingly, for the "real" outer diameter "pipe in." must be added the thickness of the walls of the pipe 2 (light weight, ordinary or rigid wall). Gain insight and clarity with Rob Daley. Transcript inch system of ordinary water and gas pipes (translated to metric and vice versa): Tube 1 / 2 inch – 15mm (Pipe dn 15) Pipe 3 / 4 inch – 20mm (tube dn 20) Pipe 1 inch – 25mm (tube dn 25) pipe 1 1 / 4 inch – 32mm (tube dn 32) pipe 1 1 / 2 inch – 40mm (Pipe dn 40) 2-inch pipe – 50 mm (tube dn 50) The legacy of the inch system of units of Russia got to include not only water and gas pipes, and carvings, which they cut. Water and gas pipes according to gost 3262-75 made with 1) normal, 2) increased accuracy of rolling, and in both cases, tolerances by weight shall not exceed 8%.
The length of pipe in the production can be from 4m to 12m, depending on the tu manufacturer, rolling conditions, the length of workpiece (strip), the buyer's order, etc. Pipe dn 15 can be performed without the black coating and a galvanized coating that is applied by thermal diffusion or electrolytic galvanizing. The galvanized coating is better resists aggressive media, the process of rusting, and therefore the life of galvanized pipes higher than the usual black water and gas pipes. Accordingly, the cost of galvanized pipe is higher than the water-gas steel pipe. dn 15 pipe is used for piping (in the industrial and civil engineering), heating systems, in as a "box" for the laying of cables for electrical works, etc. cc anta has a wide range of water and gas pipes at our own warehouse at St. Petersburg, highway, 4. Pipe dn 15 are readily available at an attractive price.