ASME 超声波规程.docx

1、ASME 超声波规程 CONTENTS1.Scope2.Qualification of NDE Personnel3.Procedure4.Instrument and Supplies5.Surface Preparation6.Calibration of Instrument7.Examination8.Evaluation9.Reexamination for Repaired Area and Nonconformity Control10.Post Cleaning11.ReportULTRASONIC EXAMINATION INSTRUCTIONULTRASONIC EXAM

2、INATION REPORT EVALUATION SHEET FOR ULTRASONIC EXAMINATION FOR BUTT-WELDSCALIBRATION SHEET FOR ULTRASONIC EXAMINATION (HALF V PATH)CALIBRATION SHEET FOR ULTRASONIC EXAMINATION (FULL V PATH)1.Scope1.1 This procedure is applied to ultrasonic angle beam examination technique using pulse-echo type ultra

3、sonic instrument.1.2 This procedure is applied to butt-welds of ASME Code vessels fabricated according to ASME Code Section Division 12.Qualification of NDE Personnel Personnel performing ultrasonic examination shall be qualified and certified in accordance with the requirements of HTs Written Pract

4、ice for NDE Personnel Training, Examination, Qualification and Certification based on the requirements of “SNT-TC-1A”(Current Code accepted edition).3.Procedure This procedure shall be supplemented by the ULTRASONIC EXAMINATION INSTRUCTION which shall be issued to every product and in which more det

5、ail parameters shall be specified. The Instruction shall be prepared by Level and approved by Level NDE examiner.4.Instrument and Supplies4.1 Instrument4.1.1 A pulse-echo type of ultrasonic instrument shall be used. The instrument shall be equipped with a stepped gain control calibrated in units of

6、2.0 dB or less, and have a capability of generating frequencies over the range of at least 1 to 5 MHz (see Table 1). Table 1ManufacturerTypeGain ControlFrequency, MHzShantou Ultra.InstrumentResearch Insti.CTS-26 0.5db 1-5CTS-21 2dB 1-54.1.2 Screen Height Linearity The ultrasonic instrument shall pro

7、vide linear vertical presentation within 5% of the full screen height for 20% to 80% of the calibrated screen height (base line to maximum calibrate screen point).The screen height linearity shall be qualified in accordance with “ULTRASONIC INSTRUMENT CALIBRATION PROCEDURE”.The calibration shall be

8、performed at the beginning of each period of extended use or every 3 months, whichever is less.4.1.3 Amplitude Control LinearityThe ultrasonic instrument shall utilize an amplitude control accurate over its useful range to 20%(2db) of the nominal amplitude ratio, to allow measurement of indications

9、beyond the linear range of the vertical display on the screen. The amplitude control linearity shall be qualified in accordance with “ULTRASONIC INSTRUMENT CALIBRATION PROCEDURE”.The calibration shall be performed at the beginning of each period of extendeduse or every 3 months, whichever is less.4.

10、2 Search Units (single) One of search units listed in Table 2 shall be used. Table 2Type Nominal AngleFrequency MHzSize, in (mm)Thickness Range In. (mm)2.5PK2.51016 68 2.50.390.63(1016)1(25)2.5PK21313 63.4 2.50.510.51(1313)1-4(25-100)2.5PK11313 45 2.50.510.51(1313)1-4(25-100)4.3 Basic Calibration Bl

11、ock4.3.1 Material of Basic Calibration Block The material from which the block is fabricated shall be of the same product form, and material specification or equivalent P-Number grouping as one of the materials being examined, P-Numbers 1,3,4 and 5 materials are considered equivalent, For calibratio

12、n block for dissimilar metal welds, the material selection shall be based on the material on the side of the weld from which the examination will be conducted; if the examination will be conducted from both sides, calibration reflectors shall be provided in both materials. Where two or more base mat

13、erial thickness are involved, the calibration block thickness shall be determined by the average thickness of the weld. The calibration block in which any weld is not contained shall be used. It shall received heat treatment as same as the material being examined and shall be taken from the material

14、 to be examined.4.3.2 Surface Finish The finish on the surfaces of the calibration block shall be representative of the surface finishes on the components.4.3.3 Block Quality The calibration block material shall be completely examined with a straight beam search unit. Areas that contain an indicatio

15、n exceeding the remaining back reflection shall be excluded from the beam paths required to reach the various calibration reflectors.4.3.4 Block Thickness The thickness shall be determined (see Fig.1) in accordance with the thickness of the part to be examined.4.3.5 Calibration Reflectors Side drill

16、ed holes, as calibration reflectors shall be used for setting the instrument sensitivity and generating DAC curve. The sizes and locations of the calibration reflectors are shown in Fig.1. Additional reflector (notch) is provided a reference for determining the surface defects as required.4.3.6 Cali

17、bration Block Configuration (1) For examination in materials where the examination surface diameter is greater than 20in.a block of essentially the same curvature, or alternatively, a flat basic calibration block, shall be used. (2) The basic calibration block shall be curved for materials with diam

18、eters 20in. and less. A single curved basic calibration block may be used to calibrate the examination on surfaces in the range of curvature from 0.9 to 1.5 times the basic calibration block diameter. The curvature range from 0.94 in. to 20 in. (24 to 508mm) diameter requires 6 block curvatures as i

19、ndicated in Fig.2 for any thickness range. 4.4 Couplant Couplant having good wetting characteristics such as SAE NO. 20 or NO.30 motor oil, or glycerin shall be used in this examination, The same couplant shall be used for calibration and examination.5.Surface Preparation5.1 Base Metal The surface o

20、f base metal on each side of the weld shall be free of weld spatter , surface irregularities, or foreign matter that might interfere with the search unit moving and coupling. If necessary, the surface shall be ground so that the metal luster shall be seen. In general, the width of preparation on the

21、 each side of the weld shall not less than distance of search unit moving.5.2 Weld Metal Where the weld surface interferes with the examination, the weld shall be prepared as needed to permit examination.6. Calibration of Instrument6.1 Frequency In general, the nominal frequency shall be 2 MHz to 2.

22、5 MHz, 2.5 MHz or 5 MHz shall be recommended for the part thickness less than 5/8 in. (16mm).6.2 Beam Angle An angle shall be selected as appropriate for the thickness and configuration of the part being examined as described in Table 2 of para.4.2. 6.3 Sweep Range Calibration6.3.1 For a Half V Path

23、 (1) Position the search unit for the maximum first indication from the 1/4 T side drilled hole. Adjust the left edge of this indication to line 2 on the screen with delay control. (2) Position the search unit for the maximum indication from the 3/4 T side drilled hole. Adjust the left edge of this

24、indication to line 6 on the screen with the range control. (3) Repeat delay and range control adjustments until the 1/4 T and 3/4 T hole reflections start at sweep lines 2 and 6. (4) Position the search unit for maximum response from the square notch on the square surface. The indication will appear

25、 near sweep line 8. (5) Two divisions on the sweep equal 1/4 T. Basic calibration HoleWeld thickness t Block Thickness T Diameter Notch Size1in. Or less 3/4in. Or t 3/32in. Width=1/8in. To 1/4in.Over 1in. Through 2in. 1-1/2in. Or t 1/8in.Over 2in. Through 4in. 3in or t 3/16in. Depth=2% t or 0.04 inO

26、ver 4in. Through 6in. 5in or t 1/4in. Whichever is greater.Over 6in. Through 8in 7in or t 5/16in. Into the base metalOver 8in. Through 10in. 9in or t 3/8in.Over 10in. t1in. Note (d) Length=2in.minNOTE: (a) Holes shall be drilled and reamed a minimum of 1.5in. deep essentially parallel to the examina

27、tion surface (b) For curved surface, two curved blocks, one for each representative curvature: or two sets of calibration reflectors oriented 90 degree from each other shall be used (c) The tolerance for hole diameter shall be 1/32 in. The tolerance on notch depth shall be +10% and 20%. The toleranc

28、e on hole location through the thickness shall be 1/8 in. (d) For each increase in weld thickness of 2 in. or fraction thereof over 10 in., the whole diameter shall increase 1/16 in. Fig.1 Basic Calibration BlockNote: (a) Plot examination surface of basic calibration block on diagonal (45 degree) li

29、ne (b) Draw horizontal line through that point from the 9/10 to the 3/2 in. limit line. (c) The ends of this line read on the horizontal scale give the range of examination surface diameters which may be examined with a Calibrated on this block. (d) Thickness range requirements shall also be satisfi

30、ed. Fig.2 Ratio Limits for Curved Surfaces6.3.2 For a Full V Path (1) Position the search unit for the maximum first indication from 3/4 T side drilled hole. Adjust the left edge of this indication to line 3 on the screen with the delay control. (2) Position the search unit for the maximum indicatio

31、n from 1/4 T side drilled holes (7/8 full V path). Adjust the left edge of this indication to line 7 on the screen with the range control. (3) Repeat delay and range control adjustments until the 3/4 T (3/8 full V path) and 1/4 T (7/8 full V path) hole reflection start at sweep line 3 and 7. (4) Pos

32、ition the search unit for the maximum response from the square notch on the same surface (8/8 full V path). The indication will appear near sweep line 8. (5) One division on the sweep equal T/4.6.4 Position Calibration6.4.1 For a Half V Path (Fig.3) (1) Position the search unit for maximum response from the T/4 side drilled hole. Plac