1、StandardTest MethodHoliday Detection of Internal Tubular Coatings ofLess Than 250 m (10 mils) Dry-Film ThicknessThis NACE International standard represents a consensus of those individual members who havereviewed this document, its scope, and provisions. Its acceptance does not in any respectpreclud
2、e anyone, whether he has adopted the standard or not, from manufacturing, marketing,purchasing, or using products, processes, or procedures not in conformance with this standard.Nothing contained in this NACE International standard is to be construed as granting any right, byimplication or otherwise
3、, to manufacture, sell, or use in connection with any method, apparatus, orproduct covered by Letters Patent, or as indemnifying or protecting anyone against liability forinfringement of Letters Patent. This standard represents minimum requirements and should in noway be interpreted as a restriction
4、 on the use of better procedures or materials. Neither is thisstandard intended to apply in all cases relating to the subject. Unpredictable circumstances maynegate the usefulness of this standard in specific instances. NACE International assumes noresponsibility for the interpretation or use of thi
5、s standard by other parties and acceptsresponsibility for only those official NACE International interpretations issued by NACE Internationalin accordance with its governing procedures and policies which preclude the issuance ofinterpretations by individual volunteers.Users of this NACE Internationa
6、l standard are responsible for reviewing appropriate health, safety,environmental, and regulatory documents and for determining their applicability in relation to thisstandard prior to its use. This NACE International standard may not necessarily address allpotential health and safety problems or en
7、vironmental hazards associated with the use ofmaterials, equipment, and/or operations detailed or referred to within this standard. Users of thisNACE International standard are also responsible for establishing appropriate health, safety, andenvironmental protection practices, in consultation with a
8、ppropriate regulatory authorities ifnecessary, to achieve compliance with any existing applicable regulatory requirements prior to theuse of this standard.CAUTIONARY NOTICE: NACE International standards are subject to periodic review, and may berevised or withdrawn at any time without prior notice.
9、NACE International requires that action betaken to reaffirm, revise, or withdraw this standard no later than five years from the date of initialpublication. The user is cautioned to obtain the latest edition. Purchasers of NACE Internationalstandards may receive current information on all standards
10、and other NACE Internationalpublications by contacting the NACE International Membership Services Department, 1440 SouthCreek Drive, Houston, Texas 77084-4906 (telephone +1 281 228-6200).Reaffirmed September 2002Reaffirmed March 1994Reaffirmed September 1989Approved 1984NACE International1440 South
11、Creek DriveHouston, Texas 77084-4906+1 (281) 228-6200ISBN 1-57590-152-82002, NACE InternationalNACE Standard TM0384-2002Item No. 21216TM0384-2002NACE International i_ForewordThis NACE standard test method was prepared as a guide for evaluating the application ofpolymeric coatings of less than 250 m
12、(10 mils) dry-film thickness to the internal surfaces ofmetallic tubular goods used in the oil and gas industry. It is not intended to provide a means ofpredicting the service life or service performance of these coatings. This test method is based onthe current technology and experience of the petr
13、oleum production industry. NACE StandardTM01861addresses holiday detection of internal tubular coatings of 250 to 760 m (10 to 30 mils)dry-film thickness. This standard is intended for use by end users of internally plastic-coated (IPC)tubular goods and accessories, as well as applicators and coatin
14、g inspectors.This standard was originally prepared in 1984 by NACE Task Group T-1G-9 on Holiday Testing ofPlastic Linings, a component of Unit Committee T-1G on Protective Coatings, Elastomers, andOther Nonmetallic Materials for Oilfield Use, and was reaffirmed by T-1G in 1989 and 1994. It wasreaffi
15、rmed in 2002 by Specific Technology Group (STG) 33 on Oil and Gas ProductionNonmetallics and Wear Coatings (Metallics). This STG is comprised of representatives from the oiland gas industry including consumers, producers, and interested individuals. This standard isissued by NACE International under
16、 the auspices of STG 33.In NACE standards, the terms shall, must, should,andmay are used in accordance with thedefinitions of these terms in the NACE Publications Style Manual,4thed., Paragraph 7.4.1.9. Shalland must are used to state mandatory requirements. Should is used that which is considered g
17、oodand is recommended but is not absolutely mandatory. May is used to state that which isconsidered optional._TM0384-2002ii NACE International_NACE InternationalStandardTest MethodHoliday Detection of Internal Tubular Coatings of Less Than250 m (10 mils) Dry-Film ThicknessContents1. General . 12. Te
18、st Apparatus 13. Calibration and Test Procedure 24. Reporting Test Data 35. Safety 3References 4Figure 1Holiday Detection, Less Than 250 m (10 mils) 1Figure 2Test Apparatus. 2_TM0384-2002NACE International 1_Section 1: General1.1 This NACE standard provides a nondestructive methodfor the detection o
19、f holidays in a nonconductive coating filmthat has been applied to the inner wall of oilfield tubulargoods. The apparatus and the recommended procedure forconducting the test are described, as are methods ofreporting the test data.1.2 The test method applies to coatings that have aspecified maximum
20、dry-film thickness of 250 m (10 mils).It is valid for coatings that have not been in service orpreviously tested with a salt solution. When holiday testingis performed on coatings that have been in service or thathave been previously tested for holidays with a salt solution,there is a possibility of
21、 misleading results arising fromsurface contamination or salt bridging. The coating surfaceshall be free of materials that give added electricalinsulation or that can mechanically damage the coatingduring the test.1.3 A “holiday” is defined as a discontinuity in a protectivecoating that exposes unpr
22、otected surface to theenvironment. For this test method, it means an area ofapplied coating that exhibits electrical resistance of lessthan some specified value when that area is contacted witha wet sponge and detected with an appropriate instrument.1.4 The specified resistance for holiday detection
23、 is 80,000ohms 10% when measured between the wet probesponge and the pipe substrate.1.5 Several internal tubular coatings have a manufacturersspecified thickness range of 200 to 330 m (8 to 13 mils).These coatings shall be tested with a wet sponge at 67.5 V(DC) and 80,000 ohms (10%) resistance._Sect
24、ion 2: Test Apparatus2.1 Apparatus and material required to perform this holidaytest include a probe, a lance, a detector, and a wettingsolution (see Figures 1 and 2).FIGURE 1Holiday detection, less than 250 m(10mils)TM0384-20022 NACE InternationalFIGURE 2Test Apparatus2.1.1 ProbeThe composition and
25、 dimensions of theprobe are as follows:(a) The probe shall be a cylindrical piece of spongethat is conductive when wetted with the wettingsolution.(b) The sponge contact area shall be a minimum of77 cm2(12 in.2) or at least 5 cm (2 in.) thick. Thediameter of the sponge shall be cut sufficiently larg
26、erthan the inside diameter of the pipe to ensure a 360-degree contact throughout the pipe length.(c) Pipe sizes that are too large to practically use a360-degree contact probe (e.g., 50-cm 20-in. diameterpipe) may require a probe that covers less than 360degrees of the pipe. In this case, the probe
27、shall be runthrough the pipe a sufficient number of times to coverthe entire coating surface. In very large-diameter pipe,a hand-held probe may be used, provided that theentire coated surface is holiday tested.(d) The probe back-up plates (see Figure 2) shall beconstructed of a material and in a man
28、ner such thatthey will not damage the coating.2.1.2 LanceThe probe shall be attached to a lance,which shall be a nonconductive tube.2.1.3 Electrical LeadsInsulated electrical conductorscapable of handling a minimum of 100 mA at 100 Vdirect current (DC) shall be used to connect thedetector to the pro
29、be and the outside pipe wall (seeFigure 1).2.1.4 DetectorThe detector is an electrical circuitcontaining the following components:(a) a sensing circuit capable of detecting smallchanges in current or voltage that correspond to theresistance selected;(b) a DC power supply that can be set at 80,000ohm
30、s 10% and at a specific voltage up to 90 Vmaximum (typically 67.5 V); and(c) an alarm circuit consisting of a light and anaudible signal that is actuated by the sensing circuit inless than 50 milliseconds.2.2 The wetting solution shall be specified by the customer.The wetting solution used to wet th
31、e probe shall be tapwater (not deionized or distilled) with additions of 0% to 3%by weight sodium chloride and a small amount (1 mL/L 1tsp/gal) of a suitable wetting agent (e.g., liquid householddetergent)._Section 3: Calibration and Test Procedure3.1 CalibrationThe instrument shall be calibrated as
32、described in either Paragraph 3.1.1 or 3.1.2 to the specificresistance for holiday detection before the initial test andrecalibrated following each 3,000 m (10,000 linear ft) ofcoating tested or at least every eight hours.TM0384-2002NACE International 33.1.1 Internal Detector CalibrationIf the instr
33、ument isdesigned for internal calibration, it will have a series ofknown, fixed resistors that can be switched into thecircuit. The following procedures shall be used forinternal detector calibration:(a) Switch the instrument to “calibrate.”(b) Connect the desired calibration resistor with anaccurac
34、y of 10% across the output terminals.(c) Adjust the alarm circuit to actuate the light andaudible signals.(d) Increase the calibration resistor (usually 10,000-ohm increments) across the circuit output. The alarmshould not activate.3.1.2 External Complete Circuit CalibrationIf theinstrument is to be
35、 calibrated externally, the followingprocedure shall be used:(a) Connect a known fixed resistor with an accuracyof 10% equal to calibration value (80,000 ohms 10%)between the probe and the pipe substrate.(b) Adjust the alarm circuit to actuate.(c) Increase the calibration resistance by 5,000 to10,00
36、0 ohms and the alarm circuit should not activate.This second calibration method has the advantage ofchecking the entire circuit from probe to ground,instead of checking the internal detector circuit only.3.1.3 If the instrument cannot be calibrated, theresistance of the detector shall be checked for
37、accuracy in accordance with Paragraph 3.1.1 or 3.1.2.This check shall be conducted at the beginning of thetest and following each 3,000 m (10,000 linear ft) ofcoating tested, or after every eight hours of testing.3.2 Testing Procedures3.2.1 The probe shall be saturated with the wettingsolution befor
38、e each length of pipe is tested. Excesssolution shall be squeezed out of the sponge.3.2.2 The pipe substrate connection shall be checkedon each length of pipe by touching the probe to thebare pipe wall to activate the alarm.3.2.3 The probe shall be run through the pipe lengthand out the far end, the
39、n withdrawn from the pipe at amaximum rate of 18 m (60 linear ft) per minute.Frequent visual checks should be made to ensure thatthe probe makes full contact with the coating.3.2.4 The holiday record for each length of pipe shallconsist of the number of holidays detected on thereturn trip, i.e., as
40、the probe is withdrawn. Steps mustbe taken to prevent the wetting solution from bridging atthe pipe threads. The number of holidays shall bemarked on each pipe length._Section 4: Reporting Test Data4.1 The test report shall indicate the number of holidaysdetected in each pipe length.4.1.1 Pipe lengt
41、hs in which the alarm circuit isactivated at such a rapid rate that the holidays cannotbe counted easily shall be classified as “semi-continuous.”4.1.2 Pipe lengths in which the alarm circuit isactivated throughout the entire length shall be classifiedas “continuous.”4.2 Test voltage, test solution,
42、 resistance calibration, lancespeed, equipment description, pipe description, coatingthickness, and number of holidays detected per joint shallbe recorded._Section 5: Safety5.1 Precautions shall be taken to prevent electrical shockduring holiday testing. This is especially important when thetest equ
43、ipment is powered by the line voltage. All of themanufacturers safety instructions to prevent electric shockshall be followed.5.2 Personnel shall not operate in areas where flammablegases are present.5.3 Personnel shall not operate in areas where flammablefluids are present if a possible fire hazard exists.TM0384-20024 NACE International_References1. NACE Standard TM0186 (latest revision), “HolidayDetection of Internal Tubular Coatings of 250 to 760 m (10to 30 mils) Dry-Film Thickness” (Houston, TX: NACE).ISBN 1-57590-152-8
