USH1097H - Method for validating radiographic inspection of projectile - Google Patents

Method for validating radiographic inspection of projectile Download PDF

Info

Publication number
USH1097H
USH1097H US07/706,482 US70648291A USH1097H US H1097 H USH1097 H US H1097H US 70648291 A US70648291 A US 70648291A US H1097 H USH1097 H US H1097H
Authority
US
United States
Prior art keywords
projectile
burster
explosive
inspected
pellets
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US07/706,482
Inventor
Michael J. Burnham
Donny W. Bromley
Paul L. Stewart
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
United States Department of the Army
Original Assignee
United States Department of the Army
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by United States Department of the Army filed Critical United States Department of the Army
Priority to US07/706,482 priority Critical patent/USH1097H/en
Assigned to UNITED STATES OF AMERICA, THE, AS REPRESENTED BY THE SECRETARY OF THE ARMY reassignment UNITED STATES OF AMERICA, THE, AS REPRESENTED BY THE SECRETARY OF THE ARMY ASSIGNMENT OF ASSIGNORS INTEREST SUBJECT TO BE LICENSE. Assignors: BROMLEY, DONNY W., BURNHAM, MICHAEL J., STEWART, PAUL L.
Application granted granted Critical
Publication of USH1097H publication Critical patent/USH1097H/en
Abandoned legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • G01N23/02Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material
    • G01N23/04Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material and forming images of the material
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/22Fuels; Explosives
    • G01N33/227Explosives, e.g. combustive properties thereof

Definitions

  • each projectile burster be x-rayed to detect voids, cracks or foreign materials with the explosive, these x-rays are not consistently reliable.
  • the problem in x-raying the projectile burster contents is that the x-ray must pass through the dense metal burster tube and accurately x-ray the less dense explosive material.
  • Prior to the present invention there was no way to ensure that an absence of indicators on the developed film indicated explosive consolidation rather than a failure of the equipment to detect cracks, voids or foreign material through the metal tube walls caused by mis-calibration or mis-focus of the x-ray machine.
  • the present invention has provided a method which ensures that each x-ray machine used to x-ray projectile bursters will be properly focused and calibrated.
  • the method of the present invention involves x-raying a burster tube which contains a explosive simulant having a predetermined density and size.
  • the x-ray film is evaluated to determine whether the x-ray machine's calibration and focus need to be adjusted.
  • burster tube x-ray film from a properly calibrated and focused x-ray machine can be used as a visual comparison for assessing the size of gaps/voids in a projectile burster containing an actual explosive.
  • This invention provides a method by which to validate the calibration and focus of an x-ray machine used for the radiographic inspection of projectile bursters.
  • One aspect of the present invention provides for the use of a penetrometer, in the form of a metal burster tube which contains an explosive simulant in the form of pellets which have a known density and dimensions. The exact dimensions of the explosive simulant pellets allow for gaps/voids of a predetermined widths and depths between the pellets. An x-ray photograph of the explosive simulant containing burster is taken, and the quality and visibility of the gaps or voids on the x-ray film of the explosive simulant containing burster are used to evaluate and adjust the calibration and focus of the x-ray machine.
  • the density of the explosive-simulating pellets is similar to that of the explosive which is used in the projectile burster.
  • the dimensions of the pellets allow for gaps between the pellets having a width of 0.01 inch and depth of 0.05 inch.
  • Another aspect of the present invention provides a method for inspecting projectile bursters using a calibrated and focused x-ray machine. X-rays are taken of a projectile burster containing explosive pellets simulant in place of the regular explosive and also of a projectile burster containing explosive. Then the two x-ray films are visually compared. Excessive gaps or voids in the explosive contained within the projectile burster may result in the failure of the projectile burster to explode. Therefore inspection of the projectile bursters by this radiographic method provides a criteria by which x-rays of projectile bursters can be evaluated.
  • the criteria used to judge the acceptance or rejection of the projectile burster are as follows: Longitudinal and traverse gaps or voids of less than 0.010 inch wide are permitted. A single longitudinal gap or void may extend a maximum of 8 inches in length. However, the aggregate length of cracks in any one projectile burster shall not exceed 12 inches.
  • Another embodiment of the present invention provides for the validation of the radiographic inspection of a M825A1 projectile burster, which contains an A-5 explosive.
  • the simulant pellets contained within the penetrometer are made of inert plastic, preferably a polyacetyl polymer which has a density of 1.41-1.43 close to that of the A-5 explosive.
  • the pellets have exact dimensions which provide for a gap or void between the pellets which is 0.01 inch wide and 0.05 inch deep.
  • the present invention is not limited to the inspection of projectile bursters.
  • the methodology of placing a material of a known density within a container can be adapted by one skilled in the art for the validation of radiographic instruments used to x-ray through any dense material to actually x-ray inspect the less dense material contained within.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Food Science & Technology (AREA)
  • Medicinal Chemistry (AREA)
  • Analysing Materials By The Use Of Radiation (AREA)

Abstract

This invention provides a method used for radiographic inspection of matel within a container, where the container is a dense material and the contents to be radiographically inspected are of a less dense material.

Description

GOVERNMENTAL INTEREST
The invention described herein may be made, used or licensed by or for the Government for Governmental purposes without the payment to the inventors of any royalties thereon or therefor.
BACKGROUND
In early 1990, there was an increase in the failure of M825A1 projectile bursters to function during projectile firings. This was subsequently determined to be due to the presence of voids or cracks with the A-5 explosive within the burster tube. Each such failure results in the loss of hundreds of dollars of U.S. Army funds.
Even though it is required that each projectile burster be x-rayed to detect voids, cracks or foreign materials with the explosive, these x-rays are not consistently reliable. The problem in x-raying the projectile burster contents is that the x-ray must pass through the dense metal burster tube and accurately x-ray the less dense explosive material. Prior to the present invention there was no way to ensure that an absence of indicators on the developed film indicated explosive consolidation rather than a failure of the equipment to detect cracks, voids or foreign material through the metal tube walls caused by mis-calibration or mis-focus of the x-ray machine.
SUMMARY
The present invention has provided a method which ensures that each x-ray machine used to x-ray projectile bursters will be properly focused and calibrated. The method of the present invention involves x-raying a burster tube which contains a explosive simulant having a predetermined density and size. The x-ray film is evaluated to determine whether the x-ray machine's calibration and focus need to be adjusted.
Additionally, the burster tube x-ray film from a properly calibrated and focused x-ray machine can be used as a visual comparison for assessing the size of gaps/voids in a projectile burster containing an actual explosive.
DETAILED DESCRIPTION
This invention provides a method by which to validate the calibration and focus of an x-ray machine used for the radiographic inspection of projectile bursters. One aspect of the present invention provides for the use of a penetrometer, in the form of a metal burster tube which contains an explosive simulant in the form of pellets which have a known density and dimensions. The exact dimensions of the explosive simulant pellets allow for gaps/voids of a predetermined widths and depths between the pellets. An x-ray photograph of the explosive simulant containing burster is taken, and the quality and visibility of the gaps or voids on the x-ray film of the explosive simulant containing burster are used to evaluate and adjust the calibration and focus of the x-ray machine. Preferably, the density of the explosive-simulating pellets is similar to that of the explosive which is used in the projectile burster. The dimensions of the pellets allow for gaps between the pellets having a width of 0.01 inch and depth of 0.05 inch.
Another aspect of the present invention provides a method for inspecting projectile bursters using a calibrated and focused x-ray machine. X-rays are taken of a projectile burster containing explosive pellets simulant in place of the regular explosive and also of a projectile burster containing explosive. Then the two x-ray films are visually compared. Excessive gaps or voids in the explosive contained within the projectile burster may result in the failure of the projectile burster to explode. Therefore inspection of the projectile bursters by this radiographic method provides a criteria by which x-rays of projectile bursters can be evaluated. The criteria used to judge the acceptance or rejection of the projectile burster are as follows: Longitudinal and traverse gaps or voids of less than 0.010 inch wide are permitted. A single longitudinal gap or void may extend a maximum of 8 inches in length. However, the aggregate length of cracks in any one projectile burster shall not exceed 12 inches.
Another embodiment of the present invention provides for the validation of the radiographic inspection of a M825A1 projectile burster, which contains an A-5 explosive. The simulant pellets contained within the penetrometer are made of inert plastic, preferably a polyacetyl polymer which has a density of 1.41-1.43 close to that of the A-5 explosive. The pellets have exact dimensions which provide for a gap or void between the pellets which is 0.01 inch wide and 0.05 inch deep.
The present invention is not limited to the inspection of projectile bursters. The methodology of placing a material of a known density within a container, can be adapted by one skilled in the art for the validation of radiographic instruments used to x-ray through any dense material to actually x-ray inspect the less dense material contained within.

Claims (5)

We claim:
1. A method of inspecting projectile bursters using a properly calibrated and focused machine comprising:
x-raying a projectile burster containing explosive simulant pellets,
x-raying a projectile burster containing explosive which is to be inspected, comparing the x-ray films of the projectile burster to that of the burster containing the explosive simulant pellets, and
evaluating the x-ray film of the projectile burster based on criteria specific to the burster and explosive it contains.
2. A method as in claim 1, wherein said projectile burster to be inspected is a M825A1.
3. A method as in claim 2, wherein said projectile burster contains an A-5 explosive.
4. A method as in claim 3, wherein said criteria are:
(i) longitudinal and traverse gaps or voids of less than 0.010 inch wide are permitted,
(ii) a single longitudinal gap or void may extend a maximum of 8 inches in length, and
(iii) an aggregate length of gaps or voids in any one of said projectile burster cannot exceed 12 inches.
5. A method of inspecting x-ray film of a material within a container to determine the acceptibility or unacceptibility of gaps or voids in the material using a properly calibrated and focused machine comprising:
x-raying a test container containing pellets having a predetermined density and predetermined size,
x-raying a container containing material which is to be inspected, comparing the x-ray films of the material to be inspected to that of the test container, and
evaluating the x-ray film of the material being inspected based upon criteria specific to the container and material it contains.
US07/706,482 1991-05-28 1991-05-28 Method for validating radiographic inspection of projectile Abandoned USH1097H (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US07/706,482 USH1097H (en) 1991-05-28 1991-05-28 Method for validating radiographic inspection of projectile

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US07/706,482 USH1097H (en) 1991-05-28 1991-05-28 Method for validating radiographic inspection of projectile

Publications (1)

Publication Number Publication Date
USH1097H true USH1097H (en) 1992-08-04

Family

ID=24837782

Family Applications (1)

Application Number Title Priority Date Filing Date
US07/706,482 Abandoned USH1097H (en) 1991-05-28 1991-05-28 Method for validating radiographic inspection of projectile

Country Status (1)

Country Link
US (1) USH1097H (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6320193B1 (en) * 1999-02-26 2001-11-20 The United States Of America As Represented By The United States Department Of Energy Method for non-intrusively identifying a contained material utilizing uncollided nuclear transmission measurements

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4604649A (en) 1981-11-24 1986-08-05 Vought Corporation Radiographic inspection means and method

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4604649A (en) 1981-11-24 1986-08-05 Vought Corporation Radiographic inspection means and method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6320193B1 (en) * 1999-02-26 2001-11-20 The United States Of America As Represented By The United States Department Of Energy Method for non-intrusively identifying a contained material utilizing uncollided nuclear transmission measurements

Similar Documents

Publication Publication Date Title
US5805660A (en) Method and device for carrying out detection of at least one non-visible object containing a given material
Liao et al. An automated radiographic NDT system for weld inspection: Part I—Weld extraction
McGonnagle Nondestructive testing
US5195117A (en) Method for using secondary radiation scattering to evaluate the thickness of materials
USH1097H (en) Method for validating radiographic inspection of projectile
US6317482B1 (en) Radiological image quality indicator
SU1536215A1 (en) Method of photometric estimation of defect dimensions in direction of exposure to radiation
US3088027A (en) Reference gage for radiographic examination of tubing
JP6441184B2 (en) Structure inspection apparatus and inspection method thereof
EP0128922B1 (en) A method for producing the radiological image of an object, preferably for use in material testing, and a means for its performance
JPS6350661B2 (en)
Sim et al. Measurement of ballooning gap size of irradiated fuels using neutron radiography transfer method and HV image filter
Clifton et al. Nondestructive evaluation methods for quality acceptance of installed building materials
Notea Evaluating radiographic systems using the resolving power function
Harara Corrosion evaluation and wall thickness measurement on large-diameter pipes by tangential radiography using a Co-60 gamma-ray source
Puranik et al. Radiographic Sensitivity of Flaw Detection in Solid Rocket Propellants
RU146022U1 (en) COMBINED TEST SAMPLE OF SENSITIVITY OF RADIOGRAPHIC CONTROL
Rossi Ciampolini et al. Radiographic Inspection
Orner Brittle Fracture Prevention Through Nondestructive Testing
Azaman et al. Validation and application of computed radiography (CR) tangential technique for wall thickness measurement of 10 inch carbon steel pipe
Rens Albert W. Knott
Youshaw et al. Nondestructive Testing of Graphite for the REVMAT Program
Kasal et al. Radiography
Nakamura et al. Fundamental study on detectability of subsurface defects by radiographic testing
Oaks Nondestructive Testing of Scout Rocket Motors.

Legal Events

Date Code Title Description
AS Assignment

Owner name: UNITED STATES OF AMERICA, THE, AS REPRESENTED BY T

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST SUBJECT TO BE LICENSE.;ASSIGNORS:BURNHAM, MICHAEL J.;BROMLEY, DONNY W.;STEWART, PAUL L.;REEL/FRAME:006022/0681

Effective date: 19910522

STCF Information on status: patent grant

Free format text: PATENTED CASE