GB/T 29169-2026Petroleum and natural gas industries - Inspection and classification of used drill stem elements (English PDF)

5.1 Testing Basics

5.1.1 General Rules Manufacturers' testing requirements for drilling tools shall be in accordance with Appendix A. Each testing level shall be conducted in accordance with the requirements of Appendix B, and related... The data should meet the requirements of Appendix C, and these tests should fall into one of the following categories.

a) The tests required by the standard testing standards constitute the minimum testing requirements for drill string component classification;

b) When specified as medium-level testing, the tests required under medium-level testing constitute the minimum testing requirements for drill string component classification;

c) When a test is designated as a critical test, the tests required in the critical tests constitute the minimum test requirements for drill string component classification;

d) Inspections that are not mandatory may be determined by the owner based on the drilling conditions.

5.1.2 Appendix on Drill String Component Inspection and Classification The contents of the drill string components covered in Appendices E to K are as follows:

---See Appendix D for the selection of drill string component inspection levels;

---For testing of special drill string threaded connections, see Appendix E;

---See Appendix F for testing of special threaded connections on in-use tubing strings;

---The relevant data and methods for drill pipe material quality grading shall be in accordance with Appendix G;

---The low-magnification acid etching test method for drill pipe materials is given in Appendix H;

---See Appendix I for the inspection cycle of drill string components;

---Recommended practices for the inspection and evaluation of drill pipe internal coatings are detailed in Appendix J;

---Recommended practices for online wellhead inspection of drill string components are given in Appendix K.

7.2 Pre-testing procedures

7.2.1 Equipment Availability Before the testing work begins, the equipment should be debugged to meet the testing requirements.

7.2.2 Descriptive Comparison Before installing the equipment, the inspection agency should confirm that the drill string components to be inspected are the same as those required by the owner. This can be achieved through comparison. The work requirements and markings of the drill string components determine the characteristics, such as designation, size, inner diameter, quality code, steel grade, manufacturer, function, and threaded connection.

7.2.3 Numbering or Marking All inspections should be traceable, achievable through unique serial numbers or permanent identification marks on each drill string component. For drill pipe, this... A number or mark can be printed on the root of the external threaded connector. After a period of use, many drill string components are replaced or added. For these reasons, the permanent serial number on the joint should match the previous one. A permanent serial number is associated with the product. The permanent serial number marker and grading bar should be added after all testing work is completed.

Note. Currently, the most commonly used permanent serial numbers can usually identify the inspection level of the inspected component. The inspection level, inspection time, and other information are displayed via printed markings. The practices of testing agencies are a representative approach. Some drill string components, including drill pipe, are marked with a permanent serial number by the manufacturer or owner. This is agreed upon by the owner and the inspection agency. In certain circumstances, a permanent serial number identification system can be used in place of conventional numerical coding. With the owner's consent, any system without a permanent serial number... All components should be identified with a numerical code. It is advisable to avoid marking the new serial number in the old serial number position. The permanent serial number should be marked in a low-stress area where wear and other forms of damage are least likely to occur. Force location.

7.2.4 Downgrade All drill string components should only be graded after all necessary testing procedures required for the component have been completed. Grading may occur in all required areas. If cracks, holes, or irreparable defects are found before the inspection process is completed, should the inspection of the component be stopped upon discovery of such defects? The testing should be determined through discussion between the owner and the testing agency.

7.3 Classification markings for drill pipe and drill pipe joints

7.3.1 Permanent Markings The permanent marking indicating the drill pipe grade should be stamped in the following locations.

a) At the root of the external threaded joint on the drill pipe;

b) In low-stress areas outside the drill pipe joint cone surface, to ensure that the markings remain in place during use. It is not advisable to print stamped marks on the outer surface of the pipe. One chisel indicates "Level 1 (Superior)", two chisels indicate "Level 2", three chisels indicate "Level 3", and four chisels indicate rejection. A stamped "A" at the root of the external threaded joint indicates that the drill pipe material, including the pipe body, joint, and weld, is grade A; a stamped "TB" indicates... The marking "JB" indicates that the drill pipe material grade is the lowest among the pipe bodies, specifically grade B; the marking "JB" indicates that the drill pipe material grade is the lowest among the joints, specifically grade B; The stamped "WB" indicates that the weld seam is the lowest grade in the drill pipe material, specifically grade B; the stamped "TC" indicates that the pipe body is the highest grade in the drill pipe material. Low grade, and grade C; stamped "JC" indicates that the drill pipe material grade is the lowest among the joints, and grade C; stamped "WC" indicates that the drill pipe material grade is... The lowest grade for welds is C. See Chapter 10 for details on drill pipe material grading.

7.3.2 Paint strips and letter markings

7.3.2.1 The paint strip markings indicating the condition of the pipe body and drill pipe joints should be applied according to the following method.

a) If the drill pipe joint is of the same or higher grade than the pipe body, the marking should only be made on the pipe body;

b) If the drill pipe joint is lower than the pipe body grade, mark it on the drill pipe joint;

c) Drill pipe joints requiring thread and sealing surface repair should be marked as shown in Figure 1. Index number explanation. 1

---Painted strips on the drill pipe joint; 2

---Painted strips for pipe body and drill pipe joints. The meanings of the markings on the drill pipe paint strip are shown in the table below.

7.3.2.2 The material grade of the drill pipe should be marked by painted letters to indicate the condition of the drill pipe and drill pipe joints. The following practices should be followed.

a) Marking A on the surface of the pipe indicates that the pipe body, joints, and welds are all of grade A in the material grade of the drill pipe.

b) The mark TB on the pipe body indicates that the pipe body is the lowest grade among the drill pipe materials, specifically grade B; the mark JB indicates that the drill pipe material is of grade B. The joint is the lowest grade in the class, and is grade B; the mark WB indicates that the weld is the lowest grade in the drill pipe material, and is grade B.

c) The mark TC on the pipe body indicates that the pipe body is the lowest grade among the drill pipe materials, specifically grade C; the mark JC indicates that the drill pipe material is of grade C. The lowest grade of drill pipe joint is grade C; the mark WC indicates that the lowest grade of weld is grade C in this drill pipe material grade.

7.4 Procedure after detection

7.4.1 Classification Each pipe body, drill pipe joint, and bottom drill assembly should be classified in accordance with the requirements of Chapter 10.

7.4.2 Cleaning Remove all magnetic powder, liquid penetrant, and other substances from the threaded connection area.

7.4.3 Statistical Quantities Count the number of drill string components for each grade and determine the total number.

7.4.4 Thread protection After inspection, ensure the threaded surfaces are clean and dry. Apply a coating conforming to GB/T 23512 or the owner's specifications to the threaded surfaces of the rotary shoulder connection. Apply thread grease. The threaded area should be coated, including the shoulder, thread root, and the entire thread circumference. In low-temperature environments, the thread should be... The grease should be insulated to ensure its proper use. Threadlocker grease should not be diluted with solvents. If possible, a clean thread protector should be worn. Tighten.

7.4.5 Work area cleanup Before leaving the work site, the inspection agency shall complete the work site cleanup in accordance with the following provisions.

a) Pipe racks. Ensure that each row of components is properly placed, and that they do not roll or fall off the racks, nor are they placed directly on the ground;

b) Waste disposal. All waste generated during the testing process should be removed, and the work area should be cleaned;

c) Solvent handling. Cleaning solvents used in the workplace should be properly handled. Warning. Solvents, cleaning products, and other waste may contain hazardous materials.

7.4.6 Inspection Mark

7.4.6.1 Overview It clarifies the standardized testing criteria for drill string components in use.

7.4.6.2 Classification Each drill string component that has been inspected should be classified by the inspectors.

7.4.6.3 Drill pipe 7.4.6.3.1 Numbering or Marking Each inspected drill pipe should have a unique number or mark, and should include the inspection date, grade, and the name or code of the inspection unit. Complete. The symbol for the number or mark should not exceed 10mm. If a traceable permanent serial number mark is already used, this method is not required. Numbering or marking. Drill pipe grade markings should be applied after all relevant tests have been completed and should reflect the highest grade of the pipe body and drill pipe joints. Low level. 7.4.6.3.2 Paint strip 7.4.6.3.2.1 Pipe body All drill pipes in use should have a grade marked with paint strips based on the corresponding requirements. Table B.18 shows the grading requirements for drill pipes in use, and Table B.19 shows the grading requirements for drill pipes in use. The grading requirements for the working tubing string should be followed. The paint strip should ideally be located approximately 0.5m from the 35° conical surface of the external threaded joint, and the width of the paint strip should be approximately... 51mm. A 25mm wide paint strip should be applied around the circumference of any defect location on all downgraded drill pipes, encompassing the defect. The paint strip... The color should reflect the degrading level of the defect. The reason for the degrading should be marked next to the paint strip using a paint symbol or other durable symbol. 7.4.6.3.2.2 Degradation of Drill Pipe Joints For every drill pipe joint that does not meet the minimum outer diameter, inner diameter, or shoulder width requirements of Table C.6, a strip of paint should be applied down its middle. 7.4.6.3.2.3 Condition of drill pipe joints For drill pipe joints requiring professional repair due to damage to all threaded connections, a 25mm wide seal should be provided on the outer surface immediately adjacent to the sealing shoulder. The red paint band (see Figure 1). The reason for the repair should be marked on the red paint using paint symbols or other methods that can be preserved during the repair process. The mark should be placed next to the paint strip and removed after repair. All drill pipe joints that were not repaired during inspection but can be repaired on-site should have a 25mm...