Model N400 is a casing crossover sub collar designed to facilitate connection of casing and/or tools of variable connection type and sizes. Available to variable CO and thread type.
- available in sizes - от 101,6 mm to 915 mm (4 to 36 inches)
- any thread, material and wall thinkness GOST, АPI, Premium
- available as per individual customer's request
Shoes and couplings are usually used in the lower interval of the well and provide a reduction in the load on the mast when running the casing through zones with ledges and collapses in the wellbore, as well as landing sites for the lower and upper cementing plug. The back pressure valve prevents fluid from flowing into the casing when the pipe is lowered into the well and prevents cement entry back into the casing after injection, while allowing circulation through the casing.