Pipes (tubes)
Tubes and tube sections are hollow products, coiled or not coiled in coils, having a constant cross-section with only one closed cavity throughout the entire length of the product in the shape of circles, ovals, rectangles (including squares), equilateral triangles, or regular convex polygons, and having a uniform wall thickness. Products with a rectangular (including square), equilateral triangular, or regular convex polygonal cross-section with rounded corners along their entire length should also be classified as tubes and tube sections provided that their internal and external cross-sections are concentric and have the same shape and orientation. Tubes and tube sections having the aforementioned cross-sections may be polished, coated, bent, threaded, drilled, tapered, expanded, coned, or fitted with flanges, gaskets, or rings at their ends.
Source: "COMMUNITY OF INDEPENDENT STATES EXTERNAL TRADE NOMENCLATURE (CTN CIS)"
Понятие «трубы (трубки)» женского рода.
| Падеж | Единственное число | Множественное число |
|---|---|---|
| Р | трубы (трубки) | труб (трубки) |
| Д | трубе (трубки) | трубам (трубки) |
| В | трубу (трубки) | трубы (трубки) |
| Т | трубой (трубки) | трубами (трубки) |
| П | трубе (трубки) | трубах (трубки) |