System and method for forming a continuous strip/plate from a plurality of strips/plates and for forming a pipe from the continuous strip/plate
A system and method of forming a continuous strip from a plurality of strips, each strip having a leading end and a trailing end. Embodiments can include a forming apparatus that chamfers at least one of the leading and trailing ends of each strip. The chamfered trailing ends may then be positioned against chamfered leading ends of successive ones of the plurality of strips. Once a leading end and a trailing end are positioned against one another, a first welding apparatus may weld on a first side, from above, the trailing and leading ends positioned against each other to form weld joints. Once at least two strips have been welded together, the strips can constitute the continuous strip. An inverting apparatus can then invert the continuous strip and weld joints. The inversion of the weld joints can be done so as not to create a reverse bend in the continuous strip. A second welding apparatus can then weld on a second side opposite the first side, from above, the inverted weld joints to form weld junctions. A pipe forming apparatus can form a pipe using the continuous strip, wherein the successively welded-together strips can be continuously or semi-continuously supplied to the pipe forming apparatus to form the pipe.
1. A method of forming a continuous strip from a plurality of strips, each of said plurality of strips having a leading end and a trailing end, the method comprising:
chamfering at least one of the leading and trailing ends of each of said plurality of strips;
positioning chamfered leading ends against chamfered trailing ends of successive ones of said plurality of strips;
welding on a first side, from above, the trailing and leading ends positioned against each other to form a first weld joint between successive strips, said welding thereby forming the continuous strip;
inverting the continuous strip and first weld joint so as not to create a reverse bend in the continuous strip and to position a second side of continuous strip to face up; and
welding on the second side, from above, along bottom side of the inverted first weld joint to form weld a junction between successive strips.
2. The method according to claim 1 , further comprising:
successively uncoiling each said strip from a coiled configuration having a first bend direction, said uncoiling including feeding the leading and trailing ends from a top position of the coiled configuration.
3. The method according to claim 2 , further comprising:
before said uncoiling, successively supplying each said strip in its coiled configuration to an uncoiling apparatus.
4. The method according to claim 2 , wherein said successively uncoiling includes feeding the leading end of said strip from the coiled configuration before feeding the trailing end of said strip.
5. The method according to claim 1 , wherein said chamfering includes:
forming a ‘Y’ cut in the at least one leading and trailing ends;
discarding a scrap end of each end that is ‘Y’ cut; and
chamfering each end that is ‘Y’ cut to form an ‘X’ chamfer.
6. The method according to claim 1 , further comprising:
reducing an overweld portion at the weld joint, if the overweld portion is produced by said welding on said first side; and
reducing an overweld portion at the weld joint, if the overweld portion is produced by said welding on said second side.
7. The method according to claim 6 , wherein said reducing of the first overweld portion occurs before said reducing of the second overweld portion.
8. The method according to claim 6 , wherein said reducing of the first overweld portion occurs before said welding of the second side of the inverted weld joint.
9. The method according to claim 1 , further comprising:
testing each said weld junction by ultrasonic testing, said testing occurring after said welding, from above, the inverted weld joints.
10. The method according to claim 6 , further comprising:
testing each said weld junction after said grinding the second overweld portion.
11. The method according to claim 1 , further comprising:
forming a pipe using the continuous strip, said forming occurring without creating a reverse bend in the continuous strip.
12. The method according to claim 2 , further comprising:
forming a pipe by spirally welding the continuous strip, the pipe being formed such that the first bend direction of the strips faces the interior of the pipe.
13. The method according to claim 1 ,
wherein said welding on the first side, from above, the trailing and leading ends to form the first weld joint is performed by a first welding apparatus; and
said welding on the second side, from above, along the bottom side of the inverted first weld joint is performed by a second welding apparatus.