Abstract:
In a method of producing a steel pipe by shaping a steel plate subjected to edge bending into a cylindrical form through plural times of three-point bending press in widthwise direction and welding a seam thereof to form a non-expanded pipe (1), inserting a pipe expander provided with plural expander tools (2) into an inside of the non-expanded pipe to perform pipe expanding, the expander tools (2) are pushed onto all sites of non-deformation areas (9) in three-point bending press to perform pipe expanding, whereby a steel pipe having an excellent roundness is produced in a high productivity. Moreover, the number of times of the three-point press bending in the above production method is (aN - 1) wherein a is an integer of 1, 2 or the like when the number of the expander tools is N.
Abstract:
In this method for manufacturing a steel pipe, a steel sheet, the edges of which have been bent, is subjected to three-point bending a plurality of times in a widthwise direction so as to form said steel sheet into a cylinder, and after abutting parts are welded together so as to produce a pipe blank (1), a pipe expander provided with a plurality of pieces of expansion hardware (2) is inserted into the pipe blank and the pipe blank is expanded. By expanding the pipe blank with the expansion hardware (2) placed up against each section (9) of the pipe blank that was not deformed by the three-point bending, steel pipes with excellent dimensional precision can be manufactured with high yield. Letting N represent the number of pieces of expansion hardware, the three-point bending is preferably performed aN-1 times (a being an integer, e.g. 1, 2, etc.).
Abstract:
يتعلّقالاختراعببرامةتشكيل forming punch بمكبسثني bending-press بالكادتتأثربعزمالانثناء bending moment ويمكنالحصولعلىأسطوانةباستدارةٍجيدة. مايتمتوفيرهعبارةعنبرامةتشكيلبمكبسثنيتشتملعلىزوجٍمنالقوالب dies 1 أيسروأيمنيتموضعهماعندفواصلعلىطولاتجاهٍعرضيلمادةصفيحة plate material S لإسنادمادةالصفيحة S عندمكانين؛وبرامة punch 2 متحركةفياتجاهٍللاقترابأوالابتعادعنالقالبين 1 وبشكلٍمتعاقبيكبسمادةالصفيحة S فيالاتجاهالعرضيأثناءإدخالمادةالصفيحةسوياًمعالقالبين 1 لتنفيذالانثناء،حيثتشتملالبرامة 2 علىرأسبرامة punch head 2ألهاسطحمعالجة (تشكيل) K يكونفيتماسٍمعمادةالصفيحة S لكبسمادةالصفيحة S بشكلٍمقعر،ومسندبرامةيتمإمساكهبوصلهبرأسالبرامة 2ألإسنادرأسالبرامة 2أ. علاوةًعلىذلك،يكونلرأسالبرامة 2أسطحمعالجة K لهمركزسطحمعالجة working surface center O يتطابقمعمحورٍ q لمسندالبرامة 2بويتشكلبقوسٍدائريغيرمنتظميكونفيهنصفقطرفيمنطقةمركزيةفيالاتجاهالعرضيهونصفقطرأقصى. شكل 2
Abstract:
In this method for manufacturing a steel pipe a steel sheet the edges of which have been bent is subjected to three point bending a plurality of times in a widthwise direction so as to form said steel sheet into a cylinder and after abutting parts are welded together so as to produce a pipe blank (1) a pipe expander provided with a plurality of pieces of expansion hardware (2) is inserted into the pipe blank and the pipe blank is expanded. By expanding the pipe blank with the expansion hardware (2) placed up against each section (9) of the pipe blank that was not deformed by the three point bending steel pipes with excellent dimensional precision can be manufactured with high yield. Letting N represent the number of pieces of expansion hardware the three point bending is preferably performed aN-1 times (a being an integer e.g. 1, 2 etc.).
Abstract:
PROBLEM TO BE SOLVED: To provide a UO steel pipe welding bead position detector capable of inexpensively and accurately detecting a welding bead position of UO steel pipe. SOLUTION: When a UO steel pipe 1 is rotated in a circumferential direction by a turning roll 3 under a condition that a touch roller 6, disposed immediately beneath an axis of the UO steel pipe 1, contacts a circumferential surface of the UO steel pipe 1, an output of a pair of two laser-type displacement gauges 9 changes between before and after a welding bead 2 of the UO steel pipe 1 hurdles the touch roller 6, therefore, the positions of entry and exit sides of the welding bead 2 can be determined from the change of output of the laser-type displacement gauges 9 and the interlevel can be calculated as the position of the welding bead 2. In addition, detection accuracy can be improved by making the position, where an absolute value of the differentiated value of the output in the pair of two laser-type displacement gauges 9 exceeds a predetermined value, at the position of entry or exit side of the welding bead 2. COPYRIGHT: (C)2011,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide a method of manufacturing a steel pipe having excellent dimensional accuracy, by which a time required for manufacturing the steel pipe is shortened by reducing the number of times of three point bending, and also the deterioration of characteristics is prevented by performing correction of a shape by cold forming.SOLUTION: After forming the steel plate which is subjected to end bending by performing the three point bending of a plurality of the number of times in the width direction, by inserting a plurality of pipe expanding tools 2 into the inside of the steel pipe 1 the butted part of the steel plate of which is welded, the steel pipe 1 is expanded by bringing the tube expanding tools 2 into contact with all of undeformed parts 9 where deformation caused by the three point bending is not produced.
Abstract:
PROBLEM TO BE SOLVED: To provide an O-press die which attains reduction in the production cost of a UOE tube of an intermediate outside diameter and enlargement of a range of produceable diameter of the UOE tube under the conventional expansion condition without degrading work efficiency, in production of the UOE tube of an intermediate outside diameter in a production line of the UOE tube of which the produceable diameter is determined for each size of the O-press die step by step, and to provide a method for producing the UOE tube by using the O-press die. SOLUTION: The O-press die for the UOE tube contains upper and lower dies 2A, 2B which are arranged on the upper and lower sides, wherein inner surfaces of the upper and lower dies have a shape formed by cutting a part of upper and lower halves of a transverse oval shape so that the inner surfaces of the upper and lower dies are transverse oval in shape when the gap Go between the upper and lower dies is set to be a predetermined value, and so that the inner surfaces of the upper and lower dies are connected to each other without any step when the upper and lower dies are tightly attached to each other. The UOE tube is produced by using the die. COPYRIGHT: (C)2011,JPO&INPIT