EP 2281641 A1 20110209 - METHOD FOR PRODUCING SEAMLESS PIPE
Title (en)
METHOD FOR PRODUCING SEAMLESS PIPE
Title (de)
VERFAHREN ZUR HERSTELLUNG EINES NAHTLOSEN ROHRS
Title (fr)
PROCÉDÉ DE FABRICATION D'UN TUBE SANS SOUDURE
Publication
Application
Priority
- JP 2009053652 W 20090227
- JP 2008082734 A 20080327
Abstract (en)
Disclosed is a method for producing a seamless pipe by using a piercing mill which pierces and rolls a round billet heated to 1300°C or lower, wherein the piercing mill is composed of a pair of skew rolls disposed to face each other across a pass line, a pair of guide devices disposed to face each other across the pass line, and a plug disposed along the pass line, between the pair of the skew rolls and also between the pair of the guide devices, wherein the piercing-rolling is performed under the conditions satisfying the following formulas (1) to (3) to prevent wrinkle flaws of the seamless pipe: - 1.0 < ”¸ ”¸ = ¸ p - ¸ r - 0.37 × ”¸ + 1.47 ‰¤ R n ‰¤ 0.37 × ”¸ + 2.67 wherein the meanings of the individual symbols in the above-described formulas are as follows: ¸ r : The half angle (°) between the pass line and the main roll face in the condition of the feed angle of the main rolls being zero ¸ p : The half angle (°) between the pass line and the reeling section of the plug R n : The number of times of the reeling of the plug
IPC 8 full level
B21B 19/04 (2006.01); B21B 27/02 (2006.01)
CPC (source: EP US)
B21B 19/04 (2013.01 - EP US); B21B 25/00 (2013.01 - EP US); B21B 27/025 (2013.01 - EP US)
Designated contracting state (EPC)
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK TR
Designated extension state (EPC)
AL BA RS
DOCDB simple family (publication)
EP 2281641 A1 20110209; EP 2281641 A4 20131002; BR PI0910031 A2 20180911; BR PI0910031 B1 20200714; CN 101980802 A 20110223; JP 4471134 B2 20100602; JP WO2009119245 A1 20110721; MX 2010010439 A 20110321; US 2011023569 A1 20110203; WO 2009119245 A1 20091001
DOCDB simple family (application)
EP 09723678 A 20090227; BR PI0910031 A 20090227; CN 200980110780 A 20090227; JP 2009053652 W 20090227; JP 2009509805 A 20090227; MX 2010010439 A 20090227; US 88498310 A 20100917