1、fiIL-STD-bd94B m 99999LL 0502493 702 m I INCH-POUND I MIL-STD-1894B 26 June 1998 SUPERSEDING 17 October 1986 MIL-STD- 1894A DEPARTMENT OF DEFENSE STANDARD PRACTICE RADIOGRAPHIC REFERENCE STANDARDS AND RADIOGRAPHIC PROCEDURES FOR PARTIAL-PENETRATION STEEL WELDS AMSC N/A AREANDTI DISTRIBUTION STATEMEN
2、T A. Approved for public release; distribution is unlimited. Licensed by Information Handling ServicesMIL-STD-LB94B 9999911 0502494 649 m MDLSTD- 1894B FOREWORD 1. This standard is approved for use by all Departments and Agencies of the Department of Defense. 2. This document contains selected radio
3、graphs illustrating various types and degrees of discontinuities occurring in partial-penetration steel welds. It also contains instructional data concerning radiographic inspection of this type of weldment. 3. It is intended that this document provide the following: a. A weld discontinuity severity
4、 range for designers to select standards for acceptance inspection. b. Reference standards for acceptance personnel to evaluate the quality of production weldments . c. Guide lines for radiographers to effectively accomplish radiographic examination of partial-penetration welds. 4. Beneficial commen
5、ts (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: U.S. Army Tank-automotive and Armaments Command, AT“: AMSTA-TR-EBLUE, Warren, MI 48397-5000, by using the Standardization Document Improvement Proposal (DD Form 14
6、26) appearing at the end of this document, or by letter. 11 Licensed by Information Handling ServicesflIL-STD-LB94B 79999LL 0502495 585 PARAGRAPH MIL-STD- 1894B CONTENTS PAGE FOREWO RD. 11 1. SCOPE . 1 1.1 Scope 1 1.2 Useofradiographs . 1 2. APPLICABLE DOCUMENTS . . . . . . . . . . . . . . . . . . .
7、 . . . . . . . . . . . 2 2.1 Gener al. 2 2.2 Government documents. . . . . . : . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2.3 Non-Government publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2.4 Order of precedence. . . . . . . . . . . . . . . . . . . . . . . . . . .
8、. . . . . . . . . 3 3. DEFINITIONS 4 3.1 Metallographic cross - sections . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3.2 Partial penetration joint design . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Penetrameter / Image quality indicator. . . . . . . . . . . . . . . . . .
9、. . . . 4 4 3.3 3.4 . Nondestructive testing terms. and definitions. . . . . . . . . . . . . . . . . . 4. 4.1 4.1.1 4.1.2 4.1.3 4.2 4.3 4.4 GENERAL REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Radiographic location . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10、 . . . . . Radiographic frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Anglebe 5 Penetrameter requirements . . . - . . . . . . . . . . . . . . . . . . . . . . . . . . . Acceptance standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Discontinui
11、tytypes . 5 5 5 5 5 5 Discontinuitygrading . 6 5. 5.1 5.1.1 5.1.2 . 5.1.3 5.1.4 5.2 DETAILED REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Application of reference standards . . . . . . . . . . . . . . . . . . . . . . . . . Determination of acceptability . , . . . . . . . -
12、. . . . Quality levels of radiographic sensitivity . . . . . . . . . . . . . . . . . . . . . Rules 1,2, and3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . False indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Inspection records . .
13、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7 7 7 7 8 8 . . . . . . . . . . . . . 6. NOTES 9 9 6.1 Intendeduse 6.2 Subject (key word) listing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 6.3 Changes from previous issue . . . . . . . . . . . . . . :
14、. . . . . . . . . . . . . . . 9 Licensed by Information Handling Services MIL-STD-1894B 9999911 0502496 qL1i MZL-STD- 1 894B FIGURES FIGURECQ 8 9 Correct and incorrect radiographic procedure for joint design (A) . . . . Reference standards for fme scattered porosity in steel welds . . . . . . . . Re
15、ference standards for coarse scattered porosity in steel welds . . . . . . Reference standards for linear porosity in steel welds , . . . . . . . . . . . . . Reference standards for clustered porosity in steel welds . . . . . . . . . . . Reference standards for scattered slag inclusions in steel wel
16、ds . . . . . . . Varying degees of incomplete penetration in steel welds correlated with weld cross-sections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lack of fusion in steel welds correlated with weld cross-sections . . . . . Recommended angle beam and film location for
17、 typical partial-penetrationjoints . i . PAGE61 10 11-12 13-14 15-16 17 is-is 20 21 22-24 iv Licensed by Information Handling ServicesMIL-STD-L94B m 99999LL 0502497 358 m MIL-STD- 1894B 1. SCOPE 1.1 Scoue. This standard provides standard reference radiographs and recommended radiographic inspection
18、procedures for partial-penetration weldments in steel plate, casting, or forging, 0.5 to 2 inches (in.) (12.70 to 50.80 millimeters (mrn) thick. 1.2 Use of radiomaDhs. The reference radiographs comprised in this standard are intended primarily for use on manual or machine arc welding with the gas me
19、tal arc, gas tungsten arc, and submerged arc welding processes. 1 Licensed by Information Handling ServicesMIL-STD-1894B 99999LL 0502498 294 MIL-STD- 1894B 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed below are not necessarily all of the documents referenced herein, but are the ones tha
20、t are needed in order to fully understand the information provided by this standard. 2.2 Government documents. 2.2.1 Soecifications, standards. and handbooks. The following specifications, standards, and handbooks form a part of this document to the extent specified herein. Unless otherwise specifie
21、d, the issues of the documents which are DoD adopted are those listed in latest issue of the Department of Defense Index of Specifications and Standards (DoDISS) and supplements hereto. STANDARDS DEPARTMENT OF DEFENSE MIL-sTD410 MIL-STD- 1941 - Nondestructive Testing Personnel Qualification and - Me
22、tal Arc Welding of Homogenous Armor. Ceaification. (Note: Negatives of radiographs illustrated in this standard can be purchased through AMSTA-TR-EBLUE. Requests should be addressed to U.S. Army Tank-automotive and Armaments Command, Attn: AMSTA-TR-/BLUE, Warren, MI 48397-5000.) (Unless otherwise in
23、dicated, copies of the above specifications, standards, and handbooks are available from the Standardization Document Order Desk, 70 Robbins Avenue, Building 4D, Philadelphia, PA 191 11-5094.) 2.3 Non-Government mblications. The following documents form a part of this document to the extent specifie
24、d herein. Unless otherwise specified, the issues of the documents which are DoD adopted are those listed in latest issue of the Department of Defense Index of Specifications and Standards (DoDISS) and supplements thereto. AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) ASTM E142 ASTM E340 - Contro
25、lling Quality of Radiographic Testing, Method - Standard Method for Macroetching Metals and Alloys for (DoD Adopted). (DoD Adopted). 2 Licensed by Information Handling ServicesMIL-STD-18948 9 911 OC02499 120 * MIL-STD-1894B ASTM E1316 ASTM E 1742 - Standard Terminology for Nondestructive Examination
26、s. - Radiographic Examination, Standard Practice for (DoD Adopted). (Application for copies should be addressed to the American Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.) 2.4 Order of precedence. In the event of a conflict between the text of this do
27、cument and the references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 3 Licensed by Information Handling ServicesMIL-STD-1894B m 9999911 0502500 772 m MIL-STD- 1
28、894B 3. DEFINITIONS 3.1 Metdloni.arhic cross sections. Cross sections through the welds as shown in figures 1 through 8, which are cut perpendicular to the direction of welding, polished and etched as specified in ASTM E340. These samples show internal discontinuity, depth of weld penetration, weld
29、size, and other characteristics of the weldment. 3.2 Partial-Denetration ioint design. The term “partial-penetration joint” as used in this standard is defined as a weld joint containing an intentionally unfsed area. Examples of typical partial-penetration joint designs are shown in figure 9. 3.3 Pe
30、netrameterhge uality Indicator CIOI) . A strip of metal the same composition as that of the metal being tested, representing a percentage of object thickness and provided with a combination of steps, holes, and/or slots. Its image on a radiograph is used to determine the radiographic quality level.
31、It is not intended for use in judging the size nor for establishing acceptance limits of discontinuities. Examples of penetrametersflQIs are shown in figures 2,3, 4,5 and 6. 3.4 Nondestructive testing terms and definitions. Nondestructive testing terms and definitions are as specified in ASTM E1316.
32、 4 Licensed by Information Handling ServicesMIL-STD-L894B 9999933 0502503 609 MIL-STD- 1894B 4. GENERAL REQUIREMENTS 4.1 Radiographic location. Weldments shall be radiographically inspected in the location specified on the applicable radiographic position chart drawing, component drawing, specificat
33、ion, or contract requirement. Radiographic inspection shall meet the requirements of MIL-STD-410 and ASTM E1742. 4.1.1 Radiographic frequency. Establishment of radiographic frequency of spot checking of weldments shall be accomplished in accordance with MIL-STD-1941. A Government approved quality as
34、surance plan has commonly been used. 4.1.2 Ande beam. Radiographic inspection of partial-penetration welds requires special consideration of joint design when selecting the angle beam. The angle employed shall insure adequate coverage of the weld with minimal interference from the normally unfused a
35、rea. Generally this can be achieved by directing the X-ray beam such that any possible incomplete penetration at both roots would be separated on the film by at least 0.125 in. (3.18 rnm). Figure 1 illustrates the radiographic results of a correct and incorrect angle beam. If a radiographic position
36、 chart is not available, the recommended procedures shown on figure 9 shall be used as a guide. 4.1.3 PenetrameterLOI requirements. Each penetrameterLQ1 shall be produced with three holes, one of which shall be a diameter equal to twice the penetrameter/IQI thickness (2T). Penetrameters/IQIs shall c
37、onform to the requirements of ASTM E142 and ASTM E1742. 4.2 Acceptance standards. Designation of acceptance standards for each type of discontinuity illustrated in the reference standards shall be made by the design activity and approved by the Government procurement agency. The specific level of ac
38、ceptance shall be designated by the “Standard Level” which is the minimum acceptance level for that discontinuity. The standard level shall be documented on the applicable radiographic position chart, drawing or contract requirement. 4.3 Discontinuitv type s. With the exception of cracks, the common
39、 discontinuities experienced in partial-penetration steel weldments are shown in the reference standards forming part of this document. These discontinuities are described below and in figures 2 through 6. All cracks shall be rejected; any deviation from this procedure will require authorization fro
40、m the Government procuring activity. a. Scattered porositv (fine and coarse). This discontinuity consists of scattered voids formed by gasses failing to escape during weld metal solidification. On the radiograph these discontinuities are dark round or elongated spots of varying size 5 Licensed by In
41、formation Handling Servicesb. C. d. e. f. MIL-STD-1894B Yqqqqll 0502502 545 MIL-STD- 1894B and density. The average size of fine porosity is 0.031 in. (0.79 mm) in diameter and that of coarse porosity is 0.063 in. (1.59 mm) in diameter. Clustered porosity. Clustered porosity appears the same as scat
42、tered porosity except that the pores are concentrated in one area, generally at the start of a bead or an interrupted arc. Linear porosity. The type most common in partial-penetration welds results from expanding gasses generated in the normally unfused area. The cavities are linearly distributed at
43、 the root of the weld deposit and generally range from 0.031 in. (0.79 111111) in diameter to 0.063 in. (1.59 mm) in diameter. Gas cavities. This discontinuity generally results from inadequate shielding gas or severe contamination of the gas. It appears the same as scattered porosity except that th
44、e average cavity size is approximately 0.125 in. (3.18 mm) in diameter. Incomdete (inadeauate) penetration. In partial penetration welds this discontinuity consists of a linear root void in excess of the unfused area normally present in this type of joint. It appears on the radiograph as a straight
45、dark line at either root or at both roots. When present at both roots the two images should be separated if properly radiographed. Lack of fusion. Lack of fusion is failure of the weld metal to fuse completely with the base metal or with the preceding bead. Lack of fusion resulting from trapped slag
46、 appears on the radiograph as a dark elongated line varying in width. Lack of fusion not accompanied by slag generally occurs along the weld interface and produces a hair-line unfused condition. This is difficult to reveal unless the plane of the discontinuity is parallel with the X-ray beam. 4.4 Di
47、scontinuitv grading. Discontinuity severity grading of the reference standards was selected to extend from standard 1, which represents a high-quality weld, to that of standard 5, which is indicative of poor workmanship and is usually rejected in commercial practice. 6 Licensed by Information Handli
48、ng Services MIL-STD-18948 D 9999911 0502503 481 MIL-STD- 1894B 5. DETAILED REQUIREMENTS 5.1 Amlication of reference standards. 5.1.1 Determination of accemability. Acceptability of production welds shall be determined by directly comparing the production radiograph with the designated reference stan
49、dard for each type of discontinuity. In general the extent of discontinuity exhibited in the designated standard will be permitted throughout the length of any particular weld joint provided that the discontinuity content in any weld length equal to that of the reference standard does not exceed that shown in the standard. Exceptions to this are required for incomplete penetration and lack of fusion since acceptability of those discontinuities is based on material thickness. The examples shown in figures 7 and 8 are for illustration purposes only; the evaluation is describe
