Fitting & Welding Cylinders
Abstract
THE EVR CHANGING FACE OF THE MARINE AND OFF-SHORE CONSTRUCTION INDUSTRIES DEMANDS MANUFACTURING METHODS FOR RE-INFORCED TUBULARS AND PRESSURE VESSELS IN CONTINUALLY INCREASING DIAMETERS, WEIGHTS, ASSEMBLED LENGTHS AND TOLERANCES. THE PRODUCTION REQUIRED CAN BE DIVIDED INTO 3 DIFFERENT CATEGORIES :- MASS PRODUCTION OF IDENTICAL ITEMS 2: LARGE BATCH PRODUCTION WITHIN A RANGE OF DIAMETERS, WEIGHTS, ASSEMBLED LENGTHS ETC. 3: NON-REPEATING SINGLE ITEMS [TAILOR MADE] CATEGORIES 1 & 2 CAN BE MECHANIZED CATEGORY 3 SHOULD BE PRODUCED BY STANDARD SHIPBUILDING PRACTICE. CATEGORY ONE CAN BE PERFORMED By THE USE OF HEAVY JIGS AND FIXTURES TO ASSEMBLE SHELLS WITHIN THE VERTICAL PLANE. AN INTEGRATED LOADING, UNLOADED AND TRANSFORT SYSTEM SHOULD BE PART OF THE PRODUCTION EQUIPMENT, THE PRODUCT IS OF GOOD QUALITY, BUT PRODUCTION IS SOMEWHAT SLOW AND THEREFORE SOME NUMBERS OF SUCH JIGS AND FIXTURES ARE REQUIRED. CARE MUST BE TAKEN NOT TO DEVELOP lNTERNAL STRESSES, WHICH COULD BE THE RESULT OF UNCONTROLLED HEAT INTRODUCTION DURING WELDING PROCEDURE. DUE TO VERTICAL MODE OF WORK, THE SYSTEM MUST BE RESTRICTED TO NOT MORE THAN TWO SHELL UNITS BEARING IN MIND THE EXTRA HEIGHT REQUIRED FOR LIFTING, TURNING AND RE-POSITIONING OF EACH UNIT. IT SHOULD BE NOTED THAT THE INITIAL INVESTMENT FOR SUCH A SYSTEM, WHICH MUST BE SUBSTANTIALLY BUILT, IS EXCEPTIONALLY HIGH. CATEGORY TWO CAN BE BEST PERFORMED THROUGH A PROGRESSIVE PRODUCTION LINE ASSISTED BY AN INTEGRATED TRANSPORT SYSTEM. AS AN EXAMPLE SUCH PRODUCTION LINE CAN BE BUILT TO COPE WITH TUBULARS/PRESSURE VESSELS OF BETWEEN 25 AND 45 FEET IN DIAMETER, A WEIGHT OF UP TO 10 TONS PER LINEAR FOOT AND TO AN UNSPECIFIED LENGTH WITHIN THE HORIZONTAL PLANE TO MEET INDIVIDUAL REQUIREMENTS. THE QUALITY OF PRODUCT WILL BE TO CLOSE TOLERANCES, WITHOUT LOCKED-IN INTERNAL STRESSES.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1985
- Accession Number
- ADA453175
Entities
People
- Stephen L. Roggendorff