ASTM D2512-95
(Test Method)Standard Test Method for Compatibility of Materials with Liquid Oxygen (Impact Sensitivity Threshold and Pass-Fail Techniques)
Standard Test Method for Compatibility of Materials with Liquid Oxygen (Impact Sensitivity Threshold and Pass-Fail Techniques)
SCOPE
1.1 This method covers the determination of compatibility and relative sensitivity of materials with liquid oxygen under impact energy using the Army Ballistic Missile Agency (ABMA)-type impact tester. Materials that are impact-sensitive with liquid oxygen are generally also sensitive to reaction by other forms of energy in the presence of oxygen.
1.2 This standard should be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 2512 – 95
Standard Test Method for
Compatibility of Materials with Liquid Oxygen (Impact
Sensitivity Threshold and Pass-Fail Techniques)
This standard is issued under the fixed designation D 2512; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope MIL-O-16791E Detergent, General Purpose (Liquid, Non-
, ,
2 3 4
ionic)
1.1 This method covers the determination of compatibil-
MIL-C-27401C Propellant Pressurizing Agent, Nitrogen
ity and relative sensitivity of materials with liquid oxygen
MIL-P-25508E Propellant, Oxygen
under impact energy using the Army Ballistic Missile Agency
MIL-T-27602B Trichloroethylene, Oxygen Propellant
(ABMA)-type impact tester. Materials that are impact-sensitive
Compatible
with liquid oxygen are generally also sensitive to reaction by
MIL-C-81302C Cleaning Compound, Solvent, Trichlorotri-
other forms of energy in the presence of oxygen.
fluorocarbon
1.2 This standard should be used to measure and describe
the properties of materials, products, or assemblies in response
3. Summary of Test Method
to heat and flame under controlled laboratory conditions and
3.1 A sample of the test material is placed in a specimen
should not be used to describe or appraise the fire hazard or
cup, precooled and covered with liquid oxygen, and placed in
fire risk of materials, products, or assemblies under actual fire
the cup holder located in the anvil region assembly of the
conditions. However, results of this test may be used as
impact tester. A precooled striker pin is then centered in the
elements of a fire risk assessment which takes into account all
cup. The plummet is dropped from selected heights onto the
of the factors which are pertinent to an assessment of the fire
pin, which transmits the energy to the test specimen. Observa-
hazard of a particular end use.
tion for any reaction is made and the liquid oxygen impact
1.3 This standard does not purport to address all of the
sensitivity of the test material is noted. Drop tests are continued
safety concerns, if any, associated with its use. It is the
using a fresh specimen cup and striker pin for each drop, until
responsibility of the user of this standard to establish appro-
the threshold valve is achieved. A series of drop tests are
priate safety and health practices and determine the applica-
conducted at an energy level of 98 J (72 ft·lbf) or as specified
bility of regulatory limitations prior to use.
for the pass-fail tests.
2. Referenced Documents
4. Significance and Use
2.1 ASTM Standards:
4.1 When this test method is used to measure the threshold
C 145 Specification for Solid Load-Bearing Concrete Ma-
5 impact sensitivity of a material, a relative sensitivity assess-
sonry Units
ment is obtained which permits the ranking of materials.
D 1193 Specification for Reagent Water
7 4.2 This test method may also be used for acceptance-
2.2 Military Standards:
testing materials for use in liquid oxygen systems. Twenty
separate samples of the material submerged in liquid oxygen
This test method is under the jurisdiction of ASTM Committee F07 on
are subjected to 98 J (72 ft·lbf) or as specified. Impact energy
Aerospace and Aircraft and is the direct responsibility of Subcommittee F07.02 on
delivered through a 12.7-mm ( ⁄2-in.) diameter contact. More
Propellant Technology.
than one indication of sensitivity is cause for immediate
Current edition approved Feb. 15, 1995. Published April 1995. Originally
e1
published as D 2512 – 66. Last previous edition D 2512 – 82 (1994) .
rejection. A single explosion, flash, or other indication of
“NASA Handbook 8060. 1B, Ambient LOX Mechanical Impact Screening
sensitivity during the initial series of 20 tests requires that an
Test,” September 1981, pp. 4-53 through 4-71. “Oxygen Systems.” George C.
additional 40 samples be tested without incident to ensure
Marshall Space Flight Center, National Aeronautics and Space Administration.
acceptability of the material.
Specification MSFC 106B. September 1981.
“Lubrication and Related Research and Test Method Development for Aviation
4.3 The threshold values are determined by this test method
Propulsion Systems.” Technical Report No. 59-726. Wright Air Development
at ambient pressure. The sensitivity of materials to mechanical
Division, January 1960.
impact is known to increase with increasing pressure. Since
“General Safety Precautions for Missile Liquid Propellants.”
Annual Book of ASTM Standards, Vol 04.05. most liquid oxygen systems operate at pressures above ambient
Annual Book of ASTM Standards, Vol 11.01.
condition, some consideration should be given to increased
Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700
sensitivity and reactivity of materials at higher pressure when
Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
D 2512
selecting materials for use in pressurized system.
5. Apparatus
5.1 ABMA-Type Impact Tester (Fig. 1), for determining the
sensitivity of materials to liquid oxygen with impact energy.
Fig. 2 shows the schematic diagram of the typical power
supply. The tester consists of the following parts:
5.1.1 Three Guide Tracks, capable of maintaining accurate
vertical alignment under repeated shock conditions.
5.1.2 Plummet, with a weight of 9.072 6 0.023 kg (20 6
0.05 lbs).
5.1.3 Safety Catch, operated by a solenoid, and designed to
hold the plummet near the base of the magnet. It is used to
support the plummet in the event of a power failure.
5.1.4 Electromagnet, for supporting or releasing the plum-
met. The electromagnet is designed to hold 9.072 kg (20 lbs) of
weight with a minimum amount of electrical energy.
5.1.5 Base—The base of the tester is composed of the
following: a rigid 0.61- by 0.61- by 0.61-m (2- by 2- by 2-ft)
(min) reinforced concrete block (concrete conforming to Speci-
fication C 145), a 3.2-mm ( ⁄8-in.) stainless steel sheet, and a
FIG. 2 Schematic Diagram of Power Supply
25-mm (1-in.) thick stainless steel base plate. Four stainless
steel foundation bolts protruding from the concrete block are
used to fasten the plate and sheet to the smooth surface of the
5.1.6 Anvil Plate (Fig. 3), made from a 51-mm (2-in.) thick
concrete block with stainless steel nuts.
Type 440B heat-treated steel plate, (56 to 58 HRC) that is
centered and rests on the base plate. It in turn centers the
NOTE 1—Where not otherwise indicated, stainless steel shall be of the
specimen cup holder.
AISI 300 series.
5.1.7 Striker Pin—The striker pins shall be machined from
AMS 5643D stainless steel, heat condition H-900 (Fig. 4).
Detail drawings for the ABMA-Type Impact Tester and Anvil Region Assembly
are available at a nominal cost from ASTM Headquarters, 100 Barr Harbor Dr., PO
5.1.8 Striker Pin Guide.
Box C700, West Conshohocken, PA 19428–2959. Order Adjunct ADJD2512.
5.1.9 Specimen Cups—One- and two-piece specimen cups
shall be used. The one-piece specimen cup (Fig. 5) shall be
used for liquid and solid test materials. When testing hard
samples that are sometimes capable of initiating reactions with
the aluminum cup, expendable Type 347 stainless steel disks
FIG. 1 ABMA-Type Impact Tester FIG. 3 Anvil Region Assembly
D 2512
a set of visual roughness comparison standards or a surface
roughness measuring instrument shall be required. Timing
instrumentation shall be required to measure the drop time of
the plummet. A suitable free-fall timing circuit is illustrated in
Fig. 10.
6. Reagents and Materials
6.1 Alkaline Cleaner, for striker pins and stainless steel
inserts, consisting of a solution of 15 g of sodium hydroxide
(NaOH), 15 g of trisodium phosphate (Na PO ), and 1 L of
3 4
distilled or deionized water.
6.2 Alkaline Cleaner, for cups; a nonetch-type solution such
NOTE 1—Break sharp edges approximately 0.015.
as Enthone NE or equivalent shall be used.
NOTE 2—Machine all surfaces 32 rums except as noted.
6.3 Aqua Regia—Mix 18 parts of concentrated HNO (sp gr
NOTE 3—Material: stainless steel AMS 5643 D.
1.42) with 82 parts of concentrated hydrochloric acid (HCl, sp
NOTE 4—Heat treatment: H-900 to obtain Rc 43 to 44.
gr 1.19) by volume.
NOTE 5—Finish: electropolish after heat treatment.
6.4 Deionized Water, conforming to Specification D 1193.
NOTE 6—Surfaces A and B should be parallel and perpendicular to the
center line within 0.001TIR and 16-32 rms along a radius. 6.5 Detergent, General-Purpose (Liquid, Nonionic), con-
All dimensions in inches.
forming to MIL-D-16791E.
FIG. 4 Striker Pin
6.6 Hydrofluoric Acid (48.0 to 51.0 %)—Reagent grade
concentrated hydrofluoric acid (HF).
11 1
6.7 Liquid Nitrogen, conforming to MIL-P-27401.
17.5 mm ( ⁄16 in.) in diameter by 1.6 mm ( ⁄16 in.) thick shall
(Warning—Contact with the skin can cause frostbites resem-
be placed in the bottom of the cup. The two-piece cup (Fig. 6)
bling burns.)
shall be used for testing semisolid materials; a one-piece insert
6.8 Gaseous Nitrogen, conforming to MIL-P-27401.
cup (Fig. 7) may also be used. The recess of either of these
(Warning—Compressed gas under high pressure. Always use
permits use of a 1.27-mm (0.050-in.) thick sample.
a pressure regulator. Release regulator tension before opening
5.1.10 Specimen Cup Holder, consisting of a 25-mm (1-in.)
cylinder.)
thick stainless steel block centered on the anvil plate. This
6.9 Liquid Oxygen, conforming to MIL-O-25508.
holder has two protruding spacers which align the striker pin
(Warning—Oxygen vigorously accelerates combustion. Con-
guide, and in turn the striker pin, with the nose of the plummet,
thus ensuring a direct hit by the nose of the plummet on the tact with skin can cause frostbite resembling burns.)
6.10 Nitric Acid (relative density 1.42)—Reagent grade
striker pin in the specimen cup.
5.2 Test Cell—The impact tester shall be housed in a test nitric acid (HNO ).
6.11 Trichloroethylene, conforming to MIL-T-27602.
cell containing a concrete floor. Walls shall be constructed of
reinforced concrete or metal to provide protection from explo- (Warning—Harmful if inhaled. High concentrations may
cause unconsciousness or death. Contact may cause skin
sion or fire hazards. The cell shall be provided with a
shatterproof observation window, and shall be darkened suffi- irritation and dermatitis.)
ciently to permit observation of flashes. The operator shall be
NOTE 2—The use of trichloroethylene is banned in California by the
located in a darkened area. Continuous ventilation shall pro-
California Air Pollution Board.
vide fresh air to the test cell. Construction of the cell shall be
6.12 Trichlorotrifluoroethane, conforming to MIL-C-
directed at providing a facility that can be maintained economi-
813202 Type I. (Warning—Harmful if inhaled.)
cally at a high level of good housekeeping. The test cell shall
be cleaned periodically to ensure cleanliness of sample and
7. Safety Precautions
equipment.
7.1 The hazards involved with liquid oxygen are very
5.3 Freezing Box, as illustrated in Fig. 8.
serious. Contact with the skin can cause frostbites resembling
5.4 Auxiliary Equipment—The auxiliary equipment shall
burns. Contact with hydrocarbons or other fuels causes an
consist of forceps for handling the specimen cups and striker
explosion hazard, as such mixtures are usually shock, impact,
pins, stainless steel spatulas, liquid oxygen handling equipment
and vibration-sensitive.
such as stainless steel Dewar flasks, liquid oxygen protective
7.2 The first-aid procedure for liquid oxygen contact is to
gloves, lintless laboratory coat, eye protection equipment, and
flush the affected area with water. This treatment should be
liquid oxygen storage containers. Special handling equipment
followed by medical attention. A safety shower must be
shall include striker pin holders (Fig. 9), specimen cup trays,
available in the immediate area.
covered storage container for specimen cups and striker pins,
7.3 The following safety rules must be observed: personnel
and a vapor-phase degreaser. The following items are also
working with liquid oxygen must be familiar with its nature
recommended: microburet, control panel with switches to
activate the safety catch and electromagnet, stereomicroscope,
American National Standard B 46.1-1962. Surface Texture standards may be
micrometer depth gage with leveling blocks, press punch cutter
used.
for preparation of plastic specimens, oven, and refrigerator. For 10
Available from Enthone, Inc., a division of American Smelting and Refining
checking surface roughness of striker pins and specimen cups, Co., Box 1900, New Haven, CT 06508.
D 2512
NOTE 1—Break sharp edges 0.015.
NOTE 2—The cup is formed by deep drawing.
NOTE 3—The thickness and parallelness of the cup bottom shall be controllled to 0.0610 to 0.0630 by coining.
NOTE 4—Materal: aluminum alloy QQ-A-318 (5052) temper H32.
All dimensions in inches.
FIG. 5 One-Piece Specimen Cup
and characteristics. Approved goggles or face shields, protec- ventilation. For cleaning by vapor degreasing, the vapor level
tive clothing, gloves, and boots must be worn during handling shall be controlled by heat input and cooling coils, which
or transfer. Such operations shall be performed by not less than establish a vapor“ ceiling.” Such vapor degreasing units should
two persons as a group. Extreme caution shall be exercised in always be installed in a location that is free from draft
preventing contact with oils or other combustible materials. All conditions and should be ventilated by horizontal slot exhausts.
tools must be degreased before use. Precautions shall be taken
8. Preparation of Apparatus
to prevent accumulation of moisture in lines, valves, traps, and
so forth to avert freezing and plugging with subsequent 8.1 General—The impact tester, its accessories, and the test
pressure ruptures. Care shall also be taken to prevent entrap- cell shall be maintained in clean condition to ensure reproduc-
ment of liquid oxygen in unvented sections of any system. ibility of results and to meet the requirements of blank testing
7.4 Safety shower and other protective equipment shall be as described in 8.5. The guide tracks, plummet, anvil plate,
inspected periodically and before each handling of liquid striker pin guide, specimen cup holder, and base plate of the
oxygen. Pe
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.