OIL TECH SERVICES, INC.

Transcription

1 OIL TECH SERVICES, INC. 800 Wilcrest, Suite 100 Houston, TX (310) (713) E Mail: mlombard@itmreps.com Website: WELDING Weld Procedure Specifications (WPS): Welding is one part of the VIT manufacturing process that requires a number of elements to be in place to insure the highest quality finished product. These elements are: appropriate materials must to be used, people performing the work must be capable, procedures must be appropriate for the work, and such procedures must be followed. Finally, appropriate inspection must take place to ensure that all of these steps have been properly executed. American Welding Society (AWS) codes contain provisions describing minimum requirements for each of these elements, and documentation is required to assure each of these elements is in place. Procedure Qualification Record (PQR): Further, these weld procedure specifications (WPS's) are qualified on a periodic basis by test. These qualification tests are conducted by welding a test sample using the parameters to be tested and by subjecting the weld to bend tests, tensile tests and, Charpy V-notch tests. Test results and variables qualified are shown in a Procedure Qualification Record (PQR). Robotic Welding on All Connection Welds: Computer Controlled Robotic Welding Post Weld Heat Treating

2 Weld Specification S Insulated Tubing 1 of SCOPE This document defines requirements for the qualification of welding operators, production welding, quality assurance and records keeping. These requirements are applicable to all vacuum sealing welds used in the manufacture of Thermal-Tube insulated tubulars and related equipment. This specification defines the requirements of Oil Tech Service, Inc. (OTSI) proprietary process for the manufacture of insulated tubular products. Materials are typically manufactured to meet the requirements of API Specification - 5CT material grades K-55, J-55, N-80 and L-80 using manual or semi-automatic arc Welding or Pulsed Gas-Metal Welding processes. This section applies to: CTI OTSI LCI X 2.0 APPLICABILITY 2.1 Individuals Operations Manager Pipe Yard Foreman Welding Operator Stress Relief Operator Oven, Close-Out, Backfilling Personnel 3.0 APPLICABLE DOCUMENTS Applicable references follow: This specification is one part of the overall Quality Assurance Program for OTSI. Other relevant documents are listed below. In case of conflict with this specification and the Quality System Manual, the Quality System Manual shall be the ruling document. Quality System Manual ASME Section VIII Division 1 Appendix 4 ASME Section V Article

3 Weld Specification S Insulated Tubing 2 of 7 2 API Specification - 5CT Sixth Edition, April 15, DOCUMENTATION Oil Tech Service Inc. produces a Weld Procedure Specification / Parameters - Insulated Tubing (WPS) sheet, form 2.5-1, for each qualified weld procedure. The completed WPS sheet describes all of the essential, supplementary and non-essential variables applicable to the particular welding process. Each Weld Procedure Specification shall be independently numbered and a part of the Tier 3 Manual in Instruction Number 2.6. They are listed as Spec 2.6- Weld Procedure Specification No. on the Tier 3 Manual Table of Contents when they are completed. On the completed form the specification number is stated in the header, the weld procedure specification number is stated in the body of the form. A copy of the Welding Procedure Specification, of the current material being welded, must be available at the location of the production welding operation. 5.0 QUALIFICATION All production welds within the scope of this specification shall be produced by a qualified welding operator in accordance with a qualified Weld Procedure Specification. 5.1 TEST SAMPLES Macro and hardness samples are saw cut to expose the cross section of the weld for hardness surveys done by x-ray technicians to API Specification - 5CT. The hardness samples are typically approximately 3 / 8 in. thick. 5.2 PROCEDURE QUALIFICATION Oil Tech Service, Inc. conducts micro hardness survey and radiographic examination for each personnel qualification. All welds produced as part of the qualification process shall be made with complete rotating circumferential welds. TABLE WELDING VARIABLES - INSULATED TUBING 1. Material grade and specification shall be the same as for the production weld. 2. Any change in weld position in excess of 15 degrees around the weld circumference, except for the torch angle.

4 Weld Specification S Insulated Tubing 3 of Decrease in preheat in excess of 50 F. 4. Change in post weld heat treat time and temperature ranges. Tack welds shall be utilized to insure compliance with specified alignment tolerances prior to depositing the root pass. Tack welds shall be made with the same consumable and welding procedures as the root pass, if required by Welding Procedure Specification. The preheat for the tack weld shall be based on the same requirements as established for the base metal welding process. A weld repair is defined as any rework on a completed weld that requires re-melting in order to correct a fault or defect in the weld as discovered by visual or non-destructive examination. The welds of this joint of insulated tubing will be sawed or ground apart, and the joint re-built as per the original work order specifications. 5.3 HEAT TREATMENT PROCEDURE QUALIFICATION Production welds usually require Post-Weld Heat Treatment to control hardness in the heat affected zone. Post Weld Heat Treatment is usually conducted through the use of induction heating with a coil which supplies heat to all adjacent welds at the same time. Heat treatment development tests may be conducted using either the production apparatus or a laboratory furnace, however, the qualification tests are conducted using the production hardware and coil position. Hardness samples are acceptable when the maximum hardness in the heat affected zone meets the requirements of API 5CT for the proper grade of pipe. Stress Relieving, Post-Weld Heat Treatment, processes are qualified through welder qualification. The process parameters (for temperature) are monitored by a calibrated instrument. 5.4 PERSONNEL QUALIFICATION In order for a welder to be qualified to produce an initial production weld, he shall first demonstrate general welding proficiency, documented by on the job training requirements checklist, in the process specified. The welder shall then produce an acceptable sample using the specified Welding Procedures Specification on representative materials and consumable as specified in this document. The criteria for acceptance are as indicated below. 6.0 RADIOGRAPHY Test welds shall be radiographically examined over 100% for all weld surfaces. ASME Section V Article Edition shall apply for the production of quality radiographs. The ASME Section V Article Edition manuals must be maintained by approved x-ray vendor. The technique shall be as shown in Figure 8-1, below. Non-destructive examination (NDE) shall be

5 Weld Specification S Insulated Tubing 4 of 7 2 performed on the same time and operation sequence as production for welds that require stress relief. 6.1 The acceptance criteria for radiographic film interpretation shall be as follows No cracks allowed No indication of lack of fusion between weld and face of inner upset tube Rounded indications shall not exceed the limits set by ASME Section VIII Div. 1 Appendix 4, Rounded Indications Charts No slag indications that exceed inches in length.

6 Weld Specification S Insulated Tubing 5 of 7 2 Note: Fusion of the weld to the outer tube wall can not be determined from this radiograph. FIGURE RADIOGRAPHY ILLUSTRATION SOURCE Three Exposures 120 degrees Penetrameter Placed on ID Film 7.0 MACROSECTION EVALUATION Macrosection shall be examined visually and found to be free from cracks, voids, lack of penetration, lack of fusion and shall be of adequate cross section. The macro hardness survey shall be conducted in the weld metal, heat effected zone and adjacent base metal and compared with the hardness of the base metal prior to welding. As indicated previously the hardness shall meet the requirements of API 5CT for the proper grade of pipe. 7.2 WELD SPECIFICATION - EVACUATION PORT The weld specifications for the welding of the evacuation port are stated with illustration on attached figure # The welder qualification documentation is as follows. Upon completion of welder qualification it is documented on form Welder Qualified - Insulated Tubing or form Welder Qualified - Evacuation Port. These completed forms are retained in the Quality System Document and Data Storage. 8.0 RE-TESTS AND RENEWAL OF QUALIFICATION In the event that an operators test weldment fails the structural or radiography tests, the operator shall produce a new weldment for that particular test.

7 Weld Specification S Insulated Tubing 6 of 7 2 Welders are qualified for a specific weld after they have produced acceptable samples using representative hardware and produced an initial production weld which meets the requirements of this specification. Operators shall be required to re-qualify for a specific weld procedure if the operator has not welded that specific weld or comparable size and grade weld for a period of twelve (12) months or more, or if the welders reject rate, as determined by visual inspection, metallography, radiography and/or vacuum leak test, exceeds one weld unit per day for two (2) consecutive days as shown on form process control inspection. Traceability of welds made within six months is shown on station log sheets for the weld stations. Re-Qualification shall be to the same criteria and process as required for initial weld qualification. 9.0 PRODUCTION WELD QUALITY CONTROL All materials, equipment s, weld preparation, pre-treatments, welding and post treatment operations shall be performed in such a way so as to conform to the applicable Weld Procedure Specifications / Parameters. Only deviations in the non-essential variables are allowable, changes to essential or supplementary essential variables shall require re-qualification of the procedure. Insulated Tubing Welding requires a fillet weld to join the end of the upset inner tube to the inside diameter of the outer tube. The ASME Boiler and Pressure Vessel Code cannot be applied to this procedure. The objective is to produce a welded connection that is equal to or greater in strength than the outer tube body wall. Good penetration is required along the vertical surface of the inner tube upset face and along the horizontal surface of the outer tube inside diameter. Assuming a round fillet weld that is otherwise satisfactory a penetration length of 1.4 times the outer tube wall thickness or greater over both of the above described surfaces will produce an acceptable weld. The external surfaces of random sample of welds shall be visually examined for conformance of the following requirements within the above specified minimum penetrated surface lengths: 1. There shall be no cracks or visible pores greater than inch in greatest dimension; and no string or pores having an aggregate size greater than 0.10 inch. 2. There shall be no slag inclusions having a length greater than 0.1 inch. 3. Spatter on the inner tube shall be acceptable but shall be monitored as an indication of improper shield gas mix. Operations involving the qualification of personnel, the fabrication of weldments and the documentation of the procedures and processes shall be monitored by the appropriate Quality Control Inspector to assure compliance with the specifications. A copy of the relevant approved

8 Weld Specification S Insulated Tubing 7 of 7 2 Weld Procedure Specifications / Parameters shall be posted at all applicable work locations and shall be readily available to the welding operator and quality inspector TRACEABILITY Each weld operator shall identify his production, by serial number, on the appropriate station log sheet RECORDS Weld Procedure Specification / Parameters - Insulated Tubing - Form Welder Qualified - Insulated Tubing - Form Welder Qualified - Evacuation Port - Form Station Log Sheet - No. 1 Weld Station - Log Station Log Sheet - Pre Stressing and No. 2 Weld Station - Log Station Log Sheet - Pre Stressing and No. 3 Weld Station - Log Station Log Sheet - Stress Relieving Station - Log Process Control Inspection - Insulated Tubing and Threading Departments - Form FIGURES 13.0 ATTACHMENTS Weld Procedure Specification / Parameters - Insulated Tubing - Form Welder Qualified - Insulated Tubing - Form Weld Specification - Evacuation Port - Figure Welder Qualified - Evacuation Port - Form 2.5-3

9 Conveying Techniques, Oil Tech Services, Lee Contracting Form # Instruction # Weld Procedure Specification / Parameters - Insulated Tubing 1 of 1 1 WELD PROCEDURE SPECIFICATION / PARAMETERS INSULATED TUBING DATE 13 Jan 2014 TYPE Thermal Tube 3H WELD PROCEDURE SPECIFICATION NO. Job No OUTER TUBE INNER TUBE OD 4-1/2" WALL 0.250" GRADE L-80 OD 3-1/2" WALL 0.254" GRADE L-80 UPSET: OUTSIDE DIAMETER PRE HEAT TEMP RANGE: None F TO F NO PASSES 4 ROTATION SPEED RANGE: 55 TO 65 SEC/REV WELDING MACHINE: TYPE Robot VOLTS MIN 23.5 MAX 25.5 AMPS MIN 160 MAX 180 GAS ARGON 90 % CO2 10 % FLOW 35 CFH WIRE SIZE 0.045" WIRE MATERIAL Superarc L59 WIRE FEED RATE 240 TO 260 IN/MINUTE CLOCK POSITION Both WELDING AREA INTERNAL EXTERNAL PREPARED AND APPROVED BY ENGINEER OFFICER

10 Conveying Techniques, Oil Tech Services, Lee Contracting Form # Instruction # Welder Qualified - Insulated Tubing 1 of 1 0 Date: Welder Qualified - This certifies that the above mentioned is qualified to weld: OD WALL SPEC GRADE to OD WALL SPEC GRADE with upset ends. Radiography Samples-Acceptable Samples Viewed Hardness Samples-Acceptable Results Viewed on sample stress relieved Engineer Officer Copies of reports attached

11 Conveying Techniques, Oil Tech Services, Lee Contracting Figure # Instruction # Weld Specification - Evacuation Port 1 of 1 0

12 Conveying Techniques, Oil Tech Services, Lee Contracting Figure # Instruction # Weld Specification - Evacuation Port 2 of 1 0 Date: Welder Qualified - This certifies that the above mentioned is qualified to weld port hole plug to OD WALL SPEC GRADE Vacuum Test held below 20 microns Engineer Officer Copies of acceptable photos of sample viewed attached