Global Patent Index - EP 0944443 B1

EP 0944443 B1 20010328 - PROCESS FOR PRODUCING INTERNALLY PLATED PIPES

Title (en)

PROCESS FOR PRODUCING INTERNALLY PLATED PIPES

Title (de)

VERFAHREN ZUR HERSTELLUNG VON INNENPLATTIERTEN ROHREN

Title (fr)

PROCEDE DE PRODUCTION DE TUBES PLAQUES A L'INTERIEUR

Publication

EP 0944443 B1 20010328 (DE)

Application

EP 97952729 A 19971212

Priority

  • DE 9702944 W 19971212
  • DE 19653670 A 19961213

Abstract (en)

[origin: WO9825712A1] This invention concerns a process for producing internally plated pipes which, as compound pipes with an outer diameter of at least 60 mm, are used for transport of corrosive and/or abrasive fluids. To that effect, a second (inner) pipe (2) with a slightly smaller outside diameter than the inner diameter of an outer pipe (1) and a wall thickness of at least 1 mm is inserted into an outer pipe (1) of carbon steel or another more resistant metallic material. The inner pipe (2) is made out of another material, particularly of a corrosion resistant and/or wear resistant metal. Moreover, the outside pipe is reduced in diameter by forced fit using a reducing ring (4) so that the outer pipe (1) is mechanically reduced to press against the inner pipe (2). This invention is characterized in that the reduction of the diameter of the outer pipe (1) using a reducing ring (4) is only carried out to the extent that the mechanical deformation of the inner pipe, which is brought about by the pressing on of the outer pipe onto the inner pipe (2), still remains within the elastic range.

IPC 1-7

B21C 37/06; B21C 37/15

IPC 8 full level

B21C 37/06 (2006.01); B21C 37/15 (2006.01)

CPC (source: EP)

B21C 37/06 (2013.01); B21C 37/154 (2013.01)

Designated contracting state (EPC)

DE FR GB IT NL SE

DOCDB simple family (publication)

WO 9825712 A1 19980618; AU 5651398 A 19980703; DE 59703252 D1 20010503; EP 0944443 A1 19990929; EP 0944443 B1 20010328; NO 311967 B1 20020225; NO 992565 D0 19990527; NO 992565 L 19990527

DOCDB simple family (application)

DE 9702944 W 19971212; AU 5651398 A 19971212; DE 59703252 T 19971212; EP 97952729 A 19971212; NO 992565 A 19990527