Technical_Manual_33B-1-2_Appendix_1.pdf

T.O. 33B-1-2

TM 1-1500-366-23

NAVAIR 01-1A-16-2

TECHNICAL MANUAL

NONDESTRUCTIVE INSPECTION

GENERAL PROCEDURES AND PROCESS CONTROLS

(ATOS)

THIS MANUAL SUPERSEDES T.O. 33B-1-2, DATED 15 MARCH 2012.

DISCLOSURE NOTICE: This information is furnished upon the condition that it will not be released to another nation without the specific authority of the Department of the Air Force of the United States, that it will be used for military purposes only, that individual or corporate rights originating in the information, whether patented or not will be respected, that the recipient will report promptly to the United States, any known or suspected compromise, and that the information will be provided substantially the same degree of security afforded it by the Department of Defense of the United States. Also, regardless of any other markings on the document, it will not be downgraded or declassified without written approval of the originating United States agency.

DISTRIBUTION STATEMENT C: Distribution authorized to U.S. Government agencies and their contractors, Administrative or Operational Use, 31 August 1986. Refer other requests for this document to AFRL/RXSST, Tinker AFB, Oklahoma 73145-3317.

WARNING: This document contains technical data whose export is restricted by the Arms Export Control Act (Title 22, U.S.C. 2751 et seq.) or the Export Administration Act of 1979, as amended, Title 50, U.S.C., App. 2401, et seq. Violation of these export-control laws is subject to severe criminal penalties. Dissemination of this document is controlled under DoD Directive 5230.25.

HANDLING AND DESTRUCTION NOTICE: Destroy by any method that will prevent disclosure of contents or reconstruction of the document.

Published under the authority of the Secretary of the Air Force

1 APRIL 2014

SWP 106 01

SUBORDINATE WORK PACKAGE

TECHNICAL PROCEDURES

COMPUTED RADIOGRAPHY PROCESS CONTROL

EFFECTIVITY: ALL WEAPONS SYSTEMS AND SUPPORT EQUIPMENT

LIST OF EFFECTIVE SWP PAGES

Total number of pages in this SWP is 34, consisting of the following:

Page Change Page Change Page Change No. No. No. No. No. No.

1 - 33 . . . . . . . . . . . . . . . . . . . . . 0 34 Blank

TABLE OF CONTENTS

Paragraph Page

1 Introduction

1.1 General Description

1.2 General Requirements

2 Access 3 Part Preparation 4 Procedures

4.1 Display Monitor Test

4.2 Initial Test Setup/Data Capture Procedure for System Tests

4.3 System Test Evaluation for Geometric Distortion

4.4 System Test Evaluation for Slippage, Scan Line Dropout, Shading and Blooming

4.5 Laser Beam Jitter Evaluation

4.6 Spatial Resolution Evaluation

4.7 Contrast Sensitivity Evaluation

4.8 Residual Image Evaluation

4.9 Equivalent Penetrameter Sensitivity (EPS)

5 Image Plate Tests for Artifacts (Optional)

5.1 Initial Test Setup/Data Capture Procedure for IP Tests for Artifacts 6 Specific Software Procedures for

6.1 Display Monitor

6.2 Initial Test Setup/Data Capture Procedure for System Tests

6.3 Geometric Distortion Evaluation

6.4 Laser Beam Jitter Evaluation

6.5 EPS

6.6 Residual Image Evaluation

6.7 IP Artifacts

TABLE OF CONTENTS (continued)

Paragraph Page

7.1 Display Monitor

7.2 Initial Test Setup/Data Capture Procedure for System Tests

7.3 Geometric Distortion Evaluation

7.4 Laser Beam Jitter Evaluation

7.5 Residual Image Evaluation

7.6 IP Artifacts

8.1 Display Monitor

8.2 Initial Test Setup/Data Capture Procedure for System Tests

8.3 Geometric Distortion Evaluation Calibration and Measurement

8.4 Laser Beam Jitter Evaluation

8.5 Residual Image Evaluation

8.6 IP Artifacts

9 Supplemental Procedures for Select Corrective Actions 9.1 9.2

9.3 Flat field exposure procedure to reduce/eliminate residual image from an IP

LIST OF ILLUSTRATIONS

Figure Title Page

1 USAF Computed Radiography (CR) Process Control Standard (PCS) 2 USN Computed Radiography (CR) Process Control Standard (PCS) with NIST Dimensional Targets 3 USAF EPS Test Standard. Raycheck RIQR2024EPS Plaques Mounted on Raycheck RIOI-AP Absorber

Block. Only Required for Air Force Crack Detection Applications 4 SMPTE133 Test Pattern for Display Monitor Process Control 5 Simulated CR Image of PCS for Geometric Distortion 6 Simulated CR Images Illustrating Slippage, Scan Line Dropout, Shading, and Blooming 7 Simulated CR Image of Jitter Target 8 Example of Jitter 9 Line Pair Gauge for Spatial Resolution Evaluation 10 Contrast Sensitivity Gauge for Sensitivity Evaluation 11 (a) Schematic of EPS specimen showing individual plaques, thicknesses and equivalent EPS values. (b)

CR image of individual EPS plaque showing holes with properly set window and level for evaluating image

12 Layout Pattern for Performing Artifact Test on Multiple IPs

LIST OF TABLES

Number Title Page

1 Process Control Interval 2 Summary of CR Process Control Tests 3 Possible Cause and Corrective Action Recommendations for Process Control Tests 4 CR Systems Qualified for Crack Detection 5 Geometric Distortion Acceptance Criteria 6 Technique and PV Range for EPS Test 7 Process Control Test Parameters for Exposure of Multiple 14 x 17 IPs

4. PROCEDURES.

4.1 Display Monitor Test.

4.1.1 Load the SMPTE 133 Test Pattern (Figure 3) onto the high resolution monochromatic display monitor. See paragraph 6 through paragraph 8 for system specific software procedures.

NOTE

On systems that have multiple display monitors, this test is only performed on the monochromatic high resolution monitor used for viewing the radiographic image.

Figure 4. SMPTE133 Test Pattern for Display Monitor Process Control

4.1.2 Visually evaluate the following SMPTE133 Test Pattern targets as follows:

a. Verify the low and high contrast vertical/horizontal lines are visible at each corner and at the center of the test pattern. (5 locations each; targets 1 and 2 in Figure 4). At the center location, verify that a minimum of 12 line pairs (12 black, 12 white) are visible in the lower pairs of lines.

b. Verify 5% square is visible within 0% square. (Target 3 in Figure 4).

c. Verify 95% square is visible within 100% square. (Target 4 in Figure 4).

d. Verify no visible distortion of horizontal/vertical crosshatch pattern. (Targets 5 and 6 in Figure 4).

e. Acceptance Criteria/Corrective Action. If any of the test patterns discussed in steps a-d are not verified, the display monitor should be repaired or replaced before further use.

f. Documentation. Document pass/fail of the test and any corrective actions taken IAW the process control documentation requirements listed in T.O. 33B-1-1.

NOTE

Display brightness is monitored by internal software. If display brightness is inadequate, the software will alert the user that corrective action is required.

4.2 Initial Test Setup/Data Capture Procedure for System Tests.

NOTE

If x-ray tubes or CR Scanners other than those listed in the appropriate table are available, each must be qualified before being used for crack detection or welder certification. Contact the appropriate cognizant engineering authority for approval.

a. Crack Detection systems SHALL use CR system components and settings listed in Table 4.

NOTE

Welder Certification systems often use IPs that are not available in 14x17 size. When this is the case, spatial resolution (4.6), contrast sensitivity (4.7), and EPS (4.9) SHALL be performed separately using the appropriate 8x10 IP and system settings for Welder Certification systems. All other tests SHALL be performed using the CR system components and settings from Table 4.

b. Welder Certification systems SHALL use CR system components and settings listed in T.O. 00-25-252, WP 005 04, Table 3A, “CR Systems Qualified for Welder Certification”.

c. For General Use systems SHALL use CR system components and settings listed in Table 4 if applicable. Otherwise, the manufacturer’s recommended IP and CR system settings may be used.

NOTE

• The first time this test is performed on the system is considered the baseline test. Once a baseline test has been performed, subsequent tests shall use the same type of IP, cassette, parameters, and CR reader settings.

• The time elapsed between exposures and processing of the IP for process control tests shall be less than 60 minutes to ensure repeatable data.

• Evaluation procedures assume the operator has had adequate training on their specific CR software to be able to perform common post-processing functions such as image optimization using contrast/brightness or equivalent, and magnification. Additional software functions that may not be used often by the operator are referred to as special software tools and guidance is provided in paragraph 2 through paragraph 8 where necessary.

• Evaluation of all images shall be performed using the raw data (no software filters). Some vendor’s software may provide ‘area adjust‘ or ‘region-of-interest‘ (ROI) type tools which set the contract and brightness automatically for a given area of the image as selected by the operator. These tools are permitted for image evaluation.

d. Record the date of the test, model and serial number(s) of CR reader, IP, and cassette if applicable.

e. Select a 14-inch x 17-inch IP and cassette. For Crack Detection systems, the same IP type identified in Table 4 SHALL be used. For Welder Certification systems, the same IP type identified in T.O 00-25-252, WP 005 04, Table

3A SHALL be used. For General Use systems, any IP type can be used. Record the model and serial number of the IP and the cassette.

f. Record the model and serial number of the PCS. The PCS shall be centered on a 14-inch x 17-inch IP, and oriented such that it covers the entire IP. A minimum of 1/8-inch thick back screen of lead is required for all exposures.

NOTE

For VMI systems, when using the Air Force PCS (Figure 1), a 0.25 Al hole-type penetrameter must be placed on the IP under the center of the PCS. The penetrameter is used for measurement calibration which must be performed at a specific magnification.

g. Expose the PCS to X-rays. Recommended test parameters: 50kV, 3mA, 20 second exposure (80 seconds for Welder Certification), and a 48-inch Source-to-Detector Distance (SDD). Record all exposure parameters.

h. Select the CR reader settings (i.e. sensitivity, pixel pitch, speed, etc.) per the appropriate system specific section (paragraph 2 through paragraph 8), and record.

i. Scan the IP and display the CR image on the display monitor.

j. Image Acceptance Criteria. Confirm all PCS targets are visible and pixel value of the background area is not greater than 95% of the system’s max pixel value and intensity, and that the pixel value on line pair target is no less than 10% of the system’s max pixel value. Refer to Table 4 or the manufacturer’s manual to determine maximum pixel value for the system (some manufacturers may refer to pixel value as POP, gray level, or intensity). See paragraph 2 through paragraph 8 for system specific software procedures.

k. Archive the raw CR image. Record image file name.

4.4 System Test Evaluation for Slippage, Scan Line Dropout, Shading and Blooming. A visual evaluation of the CR image for multiple irregularities.

a. Adjust the magnification, if necessary, so that the CR image of the entire PCS fits within the viewable area of the display monitor.

b. Visually evaluate the image for linear Slippage, Scan Line Dropout, Shading and Blooming in the short and/or long directions of the CR image. Brightness or equivalent ONLY, may be adjusted during this evaluation to optimize image. See Figure 6 for examples and descriptions of each irregularity.

c. Slippage indications (e.g. indications highlighted by white outline) are evident as a light or dark stripes or bands oriented in the short dimension of the CR image (Figure 6, Top left). Slippage can occur in more than one location in the image, and may occur as wide or narrow indications depending on the amount of slip. Not all CR readers are susceptible to slip.

d. Scan line dropout is evident as a bright white line spanning the entire long dimension of the CR image (Figure 6, Top right). Scan line dropout can occur in multiple places within the same image and may occur as wide or narrow indications.

e. Shading is evident as light and dark bands oriented in the long direction of the CR image. (Figure 6, Bottom Left.)

f. Blooming is evident as streaking or overshoot at light to dark transition regions in the short dimension of the IP and is most noticeable at the edges of the blooming target. (Figure 6, Bottom Right.)

g. If any of the irregularities discussed in paragraph 4.3. are visible, the CR system shall be evaluated and corrective action taken per Table 3 before further use.

h. Document pass/fail of each test and any corrective actions taken IAW the process control documentation requirements listed in T.O. 33B-1-1.

Figure 7. Simulated CR Image of Jitter Target

c. Acceptance Criteria/Corrective Action. Distorted edges along the jitter target (Figure 8), which may occur at one or more locations, are indications of laser jitter and shall be evaluated and corrective action taken per Table 3 before further use.

d. Documentation. Document pass/fail of the test and any corrective actions taken IAW the process control documentation requirements listed in T.O. 33B-1-1.

Figure 8. Example of Jitter

4.6 Spatial Resolution Evaluation. Visually evaluate image for ability to resolve small details or features.

a. Adjust the magnification so that the CR image of one line pair gauge fills the viewable area of the display monitor (Figure 9).

Figure 9. Line Pair Gauge for Spatial Resolution Evaluation

b. Visually optimize image using brightness and contrast (i.e. window/level). During evaluation of the CR image of the line pair gauges, the operator shall be positioned 12-18 inches from the display monitor.

c. Visually evaluate the CR image of the line pair gauge and determine the smallest line pairs per mm (LP/mm) that are separated by a continuous visible space along the entire length of the line pair. Record the LP/mm and line pair gauge ID (A or B).

d. While maintaining the same magnification level and image viewing parameters, maneuver the image to view the other line pair gauge and evaluate it in the same manner. Record the LP/mm and line pair gauge ID (A or B).

NOTE

It is not uncommon for the spatial resolution between line pair gauges A and B to be different due to inherent differences in scanning resolution of the laser scanner in each direction (i.e. fast-scan vs. slow-scan directions).

e. Acceptance Criteria/Corrective Action

(1) For General Use systems, a minimum of 2.5 lp/mm is required in both orientations.

(2) For crack detection systems, a minimum of 6.0 lp/mm is required in both orientations.

(3) For Welder Certification systems, a minimum of 8.0 lp/mm is required in both orientations.

(4) Inability to achieve the required spatial resolution or a reduction in spatial resolution from baseline test data indicates degraded performance, and shall be evaluated and corrective action taken per Table 3 before further use.

f. Document pass/fail of the test, LP/mm for each gauge, and any corrective actions taken IAW the process control documentation requirements listed in T.O. 33B-1-1.

H0800868

Figure 10. Contrast Sensitivity Gauge for Sensitivity Evaluation

4.7 Contrast Sensitivity Evaluation. Visually evaluate image for ability to detect low contrast features.

a. Adjust the magnification so that the CR image of the contrast gauge fills the viewable area of the display monitor (Figure 10).

b. Visually optimize image using brightness/contrast, window/level, or equivalent.

c. Visually evaluate the CR image of the contrast gauge and record the number of steps that can be visually identified.

NOTE

If the steps in the contrast gauge are not visible, in the baseline test, it may be necessary to repeat the exposure for this test with different exposure parameters and record the parameters specifically for this test. Recommended alternate exposure parameters for the contrast gauge are 60kV, 5mA, and 36sec, at 48 inches.

d. Acceptance Criteria/Corrective Action. Three steps must be visually identified on the contrast sensitivity gauge, which equates to 2% contrast sensitivity (2% step highlighted by the arrow in Figure 10). Inability to achieve the required contrast sensitivity or a reduction in contrast sensitivity from the baseline test data indicates that the CR system shall be evaluated and corrective action taken per Table 3 before further use.

e. Document pass/fail of the test and any corrective actions taken IAW the process control documentation requirements listed in T.O. 33B-1-1.

4.8 Residual Image Evaluation. Evaluate image for proper erasure using special software tools.

a. Erase the IP by processing it through the CR eraser.

NOTE

Most CR systems automatically erase the IP after reading. If so, the erasure step is not required.e

b. Scan the erased IP and display the CR image on the monitor.

c. Evaluate the CR image of the erased IP by measuring the pixel value and/or intensity over the entire image using the imaging software tools. See paragraph 2 through paragraph 8 for system specific software procedures.t

d. Acceptance Criteria/Corrective Action. If the maximum intensity is greater than the value specified in the system specific acceptance criteria in paragraphs 2 through paragraph 8, the CR eraser shall be evaluated and corrective action taken per Table 2 before further use.

e. Documentation. Document pass/fail of the test and any corrective actions taken IAW the process control documentation requirements listed in T.O. 33B-1-1.

4.9 Equivalent Penetrameter Sensitivity (EPS). For Crack Detection systems only - NOT FOR NAVY USE

a. The EPS Standard (Figure 11, detail (a)) shall be imaged at a distance of 48 inches from the surface of the EPS standard to the X-ray tube. The IP shall be placed immediately beneath the specimen, within the appropriate flexible or hard cassette. A minimum of 1/8-inch thick back screen of lead is required for all exposures.

NOTE

The portion of the IP that is not covered by the EPS standard shall be shielded with lead or another material that is more radiographically dense than the EPS standard to prevent formation of a residual image in the IP after multiple exposures. If available, an 8 x 10 imaging plate may be used for this test, provided it is the same type of IP specified for use with the qualified CR system.

b. Technique parameters for kV, mA, and time shall be determined from Table 6. kV may be adjusted ±10kV, but no other technique parameters shall be changed.

c. Confirm that the pixel value (intensity) measured near the center of the 8 mil EPS plaque is within the allowable pixel value range listed in Table 6.

d. Determine the EPS performance by identifying the duplex row where a minimum of 20 holes (out of 30 holes in each duplex row) are clearly visible (Figure 11, detail (b)).

NOTE

Similar to conventional penetrameter evaluations, holes which are counted should appear round, and clearly distinguishable from the background image noise.

(1) Visually optimize the EPS image using level (brightness), window (contrast), and magnification only.

(2) Set the level of the image to the approximate pixel value (brightness) measured near the center of the 8 mil EPS plaque.

(3) Reduce the window (contrast) so that the holes can be best visualized.

(4) Magnification can be varied to determine the approximate duplex row, but for final evaluation of the EPS data, magnification shall be set at absolute magnification of 1 (i.e. 1:1 image pixel to display pixel ratio).