Tubular exchanger
AssigneeCreusot-Loire
InventorRene Henri Droin
Life of this patent
Estimating the term…
Abstract
A tubular exchanger for operations under conditions of heat and pressure comprising a set of tubes made of ferritic steel having the following composition: C .ltoreq. 0.010%, Cr 25 to 30%, Mo < 4%. The tubes are provided at each end with relatively short ferrules of austenitic stainless steel which are welded to the tubes.
Claims7
A tubular exchanger for working under heat and pressure, comprising a set of tubes made of ferritic steel of high chrome content having the following composition:
- C <
- 0.010%,
- cr:
- 25 to 30%,
- Mo <
- 4%,
- relatively short tubular ferrules of austenitic stainless steel, weld means joining said ferrules respectively to said tubes with a low degree of contamination, said stainless steel of said ferrules having the following composition:
- C <
- 0.020%,
- cr:
- 20 to 26%,
- Ni:
- 6 to 26%,
- Mo:
- 1 to 5%,
- a tube plate receiving said ferrules, said tube plate being clad with an austenitic stainless steel having the following composition:
- C <
- 0.030%,
- cr:
- 18 to 22%,
- Ni:
- 14 to 18%,
- Mo:
- 1 to 3%,
- Mn:
- 4 to 6%.
- and second weld means joining said ferrules to said cladding of said tube plate.
A tubular exchanger for working under heat and pressure, comprising a set of tubes made of ferritic steel, a ferrule of austenitic stainless steel welded to each end of each tube, and a pair of tube plates clad in austenitic stainless steel, said ferrules being welded to said cladding, and wherein said steel of said tubes has the following composition:
- C <
- 0.010%,
- cr:
- 25 to 30%,
- Mo <
- 4%,
- said steel of said ferrules has the following composition;
- C <
- 0.020%,
- cr:
- 20 to 26%,
- Ni:
- 6 to 26%,
- Mo:
- 1 to 5%,
- and said steel of said tube plate cladding has the following composition:
- C .ltoreq. 0.030%,
- cr:
- 18 to 22%,
- Ni:
- 14 to 18%,
- Mo:
- 1 to 3%,
- Mn:
- 4 to 6%.
Dependencies are inferred from the claim text.