Pipes And Tubular Conduits Patents (Class 138)
- Casing (Class 138/118.1)
- With means for facilitating collapse (Class 138/119)
- Joined sections (Class 138/120)
- Corrugated (Class 138/121)
- Braided, interlaced, knitted or woven (Class 138/123)
- Longitudinally seamed (Class 138/128)
- Spirally wound material (Class 138/129)
- Distinct layers (Class 138/137)