Method and apparatus for aligning and cutting pipe

Abstract

A method and apparatus for aligning and cutting pipes to extract and install piping in industrial plants is characterized by the use of lasers on a ring for aligning the cutting tool. By adjusting the ring so that beams from the lasers strike specified targets at a remote location corresponding with a pipe end, a cutting location is defined so that the trimmed end of a first pipe will properly align with a remote pipe. When the pipes welded together, their ends will match, thereby minimizing stress in the pipe. A cutting tool can be provided directly on the ring so that the pipe can be cut without removing the ring.

What is claimed is:  
     
         1 . An alignment device used in trimming an end face of a cylindrical pipe having a longitudinal axis, comprising 
 (a) a generally cylindrical ring;    (b) laser means connected with said ring for generating a linear laser beam; and    (c) means for adjustably clamping said ring about the circumference of the pipe in a fixed position when said laser beam is directed on a remote target corresponding with an end of another pipe to be connected with the pipe, whereby when said ring is clamped in the final position, the pipe can be marked about its circumference in accordance with the fixed position of the ring to provide an indication of where the pipe should be cut so that its cut end surface will accurately mate with the end of the other pipe.    
     
     
         2 . An alignment device as defined in  claim 1 , wherein said laser means comprises a plurality of lasers connected with said ring for generating a plurality of laser beams toward a plurality of targets.  
     
     
         3 . An alignment device as defined in  claim 2 , wherein said plurality of lasers are equally spaced around said ring.  
     
     
         4 . An alignment device as defined in  claim 3 , wherein said lasers are connected with said ring via adjustable mounting brackets, whereby laser beams from said lasers can be directed at selected angles relative to an axis of said ring.  
     
     
         5 . An alignment device as defined in  claim 1 , wherein said laser is arranged beyond the outer circumference of said ring and generates a beam parallel to an axis of said ring.  
     
     
         6 . An alignment device as defined in  claim 1 , wherein said laser is arranged within the outer circumference of said ring.  
     
     
         7 . An alignment device as defined in  claim 1 , wherein said laser is further used to measure a distance from said laser to said target, whereby said ring can be positioned to adjust the distance from the target.  
     
     
         8 . Apparatus for aligning and cutting a cylindrical pipe having a longitudinal axis, comprising 
 (a) a first frame adjustably mounted on the pipe;    (b) laser means connected with said frame for generating a linear laser beam;    (c) means for adjusting said frame on the pipe to direct said laser beam on a fixed remote target; and    (d) a cutting tool connected with said frame, said cutting tool being movable around the circumference of the pipe to cut the pipe in a configuration to mate with another pipe corresponding with the remote target.    
     
     
         9 . Apparatus as defined in  claim 8 , wherein said laser means comprises a plurality of lasers spaced about said frame.  
     
     
         10 . Apparatus as defined in  claim 9 , wherein said lasers are connected with said frame via adjustable mounting brackets, whereby laser beams from said lasers can be directed at selected angles relative to the longitudinal axis of the pipe.  
     
     
         11 . Apparatus as defined in  claim 8 , wherein said frame comprises an inner ring mounted on said pipe and an outer track which rotates relative to said inner ring about the circumference of the pipe.  
     
     
         12 . Apparatus as defined in  claim 11 , wherein said laser means are mounted on said track beyond the circumference of the pipe.  
     
     
         13 . A method for defining a cutting line for the end face of a cylindrical pipe having a longitudinal axis, comprising the steps of 
 (a) mounting a ring on the pipe about the circumference thereof;    (b) generating a linear laser beam from the ring; and    (c) adjusting the ring to a fixed position relative to the pipe to direct the laser beam onto a first fixed remote target corresponding with an end of another pipe to be connected with the pipe, whereby when the ring is adjusted to the fixed position, the ring defines a cutting location so that after cutting, the cut end surface of the pipe will accurately mate with the end of the other pipe.    
     
     
         14 . A method as defined in  claim 13 , wherein said adjusting step includes rotating the ring 90° about the pipe to direct the laser beam onto a second fixed remote target, whereby said ring is accurately positioned on the pipe relative to its longitudinal axis.  
     
     
         15 . A method as defined in  claim 13 , and further comprising the steps of measuring a first distance from said laser to said first target, rotating the ring 90° about the pipe to direct the laser beam onto a second fixed remote target, and adjusting the ring to position the laser from said second target at a distance equal to said first distance.  
     
     
         16 . A method as defined in  claim 15 , wherein said laser beam generating step comprises generating a plurality of laser beams from angularly spaced locations around the circumference of the pipe.  
     
     
         17 . A method as defined in  claim 16 , and further comprising the step of adjusting the direction of at least one of said laser beams relative to the longitudinal axis of the pipe.  
     
     
         18 . A method as defined in  claim 17 , and further comprising the step of 
 (d) cutting the pipe with a cutting tool at the cutting location.    
     
     
         19 . A method as defined in  claim 15 , and further comprising the step of 
 (d) cutting the pipe with a cutting tool at the cutting location.    
     
     
         20 . A method as defined in  claim 19 , and further comprising the steps of 
 (e) mounting the ring at a second location on the pipe; and    (f) repeating steps (b)-(d), whereby a portion of the pipe between an original cutting location and the second cutting location can be removed.    
     
     
         21 . A method as defined in  claim 20 , and further comprising the steps of 
 (g) repeating steps (a)-(d) on the ends of a replacement section of pipe;    (h) inserting said replacement section of pipe in an area vacated by the removed portion of pipe; and    (i) welding the replacement section of pipe to the original pipe.    
     
     
         22 . A method as defined in  claim 15 , and further comprising the steps of 
 (e) mounting a second ring on the pipe at a second location spaced from an original cutting location; and    (f) repeating steps (b)-(d), whereby a portion of the pipe between the original cutting location and the second cutting location can be removed.    
     
     
         23 . A method for defining a cutting line for the end face of a cylindrical pipe adjacent to an elbow portion thereof, comprising the steps of 
 (a) mounting a ring on the pipe about the circumference thereof and before the elbow portion;    (b) establishing a pair of first reference points spaced 90° relative to a longitudinal axis of another pipe to a remote location beyond the elbow portion of the pipe;    (c) establishing a pair of second reference points on the ring and spaced 90° relative to a longitudinal axis of the pipe; and    (d) adjusting the ring to a fixed position so that the pair of second reference points are oriented in a configuration corresponding to the pair of first reference points to define a cutting location so that after cutting, the cut end surface of the pipe will be in 90° alignment with the end of the first pipe.    
     
     
         24 . A method as defined in  claim 23 , and further comprising the step of adjusting the ring via triangulation.  
     
     
         25 . A method as defined in  claim 24 , wherein said second reference points comprise laser light sources mounted on the ring.  
     
     
         26 . A method as defined in  claim 25 , wherein said first reference points are defined relative to the inner bend distance of the elbow portion.  
     
     
         27 . A method as defined in  claim 26 , wherein said first reference points define target locations for beams from said laser light sources, respectively.  
     
     
         28 . A method as defined in  claim 27 , and further comprising the step of cutting said pipe at the cutting location.  
     
     
         29 . A method for aligning and cutting a cylindrical pipe adjacent to an elbow portion thereof, comprising the steps of 
 (a) mounting a frame on a first portion of the pipe about the circumference thereof;    (b) generating a first linear laser beam from the frame in a direction normal to a longitudinal axis of the first pipe at a location to be cut to a first point spaced from a second pipe by a distance corresponding to an inner bend of the elbow;    (c) measuring a second distance along said first beam from a center of said pipe first portion to said first point;    (d) measuring a third distance from said first point to a center of said second pipe;    (e) directing second and third laser beams from the frame at second and third points 90° offset from the first beam to corresponding second and third points on opposite sides of the second pipe;    (f) re-directing said first laser beam to strike a bottom portion of the send pipe;    (g) adjusting the frame so that the square of a fourth distance along said first beam between said second pipe and said frame is equal to the sum of the square of the second and third distances; and    (h) cutting the pipe with a cutting tool mounted on the frame for rotation about the circumference of the pipe, whereby the end of the pipe first portion is cut to a configuration to match the pipe second portion.