1、 MIL-DTL- 32412 10 December 2012 . DETAIL SPECIFICATION HFC-227ea FIRE EXTINGUISHING AGENT ENHANCED WITH SPECIAL SODIUM BICARBONATE POWDER (HFC-227ea/SBCS) This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification esta
2、blishes the requirements and verification methods for two HFC-227ea/SBCSFire Extinguishing agents. For the purpose of simplicity, the term Agent will be used to denote the HFC-227ea/SBCS Fire Extinguishing agents. The purpose of these two Agents is to provide Army Aviation weapon systems, when in th
3、e proper hardware configuration, with an acceptable extinguisher configuration that does not employ an extinguishing mixture classified as an ozone-depleting substance (ODS). 1.2 Classification. The two Agents are free-flowing slurries of specialized sodium bicarbonate (SBCS) powder suspended in HFC
4、-227ea that will be used in fire extinguishing hardware (see 6.5 for a list of fire extinguishing hardware specifications) which is not covered in the scope of this document. The Agents are comprised of 1,1,1,2,3,3,3-Heptafluoropropane compound (generically named HFC-227ea) containing either of two
5、SBCSpowders held in long term suspension as free-flowing slurries. The Agents will be further designated as either a Class I or Class II composition depending on the specific sodium bicarbonate employed in creating the slurry. The SBCSpowders employed in these Agents will be either of two types, des
6、ignated as SBC-1 and SBC-2. The two Agent Classes are described in detail below and will be specified in the contract or purchase order (see 6.2). AMSC N/A FSC 4210 DISTRIBUTION STATEMENT A. Approved for public release; distribution unlimited. METRIC Comments, suggestions, or questions on this docum
7、ent should be addressed to: Director, U.S. Army Research Laboratory, Weapons and Materials Research Directorate, Materials and Manufacturing Technology Branch, Specifications and Standards Office, Attn: RDRL-WMM-D, Aberdeen Proving Ground, MD 21005-5069 or emailed to richard.j.squillacioti.civmail.m
8、il. Since contact information can change, you may want to verify the currency of this address information using the ASSIST Online database at https:/assist.dla.mil/. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-32412 2 1.2.1 Class I. Class
9、 I Agents will contain SBC-1 (the sodium bicarbonate component prepared by size reduction processing (for example: utilizing Jet-Milling, as detailed in Appendix B) of United States Pharmacopeial (USP) grade sodium bicarbonate raw material). 1.2.2 Class II. Class II Agents will contain SBC-2 (from m
10、ethods of processing USP grade sodium bicarbonate starting material that produce a preponderance of nanometer particles). 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in this section are specified in sections 3, 4, or 5 of this specification. This section does not include documents cite
11、d in other sections of this specification or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements of documents cited in sections 3, 4, or 5 of this
12、specification, whether or not they are listed. 2.2 Government documents. 2.2.1 Specifications, standards, and handbooks. The following specifications, standards, and handbooks form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are t
13、hose cited in the solicitation or contract. DEPARTMENT OF DEFENSE STANDARDS MIL-STD-1916 - Preferred Methods for Acceptance of Product (Copies of these documents are available online at https:/assist.dla.mil/quicksearch/ or from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4
14、D, Philadelphia, PA 19111-5094.) 2.3 Non-Government publications. The following documents form a part of this specification to the extent specified herein. Unless otherwise indicated (see 6.2), the issue in effect on date of invitation for bids or request for proposal should apply. ASTM INTERNATIONA
15、L ASTM D6064 - Standard Specification for HFC-227ea, 1,1,1,2,3,3,3- Heptafluoropropane (CF3CHFCF3) (Copies of these documents are available from www.astm.org or ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.) 2.4 Order of precedence. Unless otherwise noted
16、herein or in the contract, in the event of a conflict between the text of this document and the references cited herein (except for related specification sheets), the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specif
17、ic exemption has been obtained. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-32412 3 3. REQUIREMENTS 3.1 First Article. When specified in the contract or purchase order (see 6.2 and 6.4), a sample shall be subjected to first article inspec
18、tion in accordance with (IAW) paragraph 4.2. 3.2 Agent sample source. Blended slurry samples shall not be obtained from a bulk tank that is pressurized above the vapor pressure of HFC-227ea. The only pressure within the bulk slurry tank shall be the vapor pressure of HFC-227ea that correlates to the
19、 temperature of the working environment. 3.3 Material and components. The materials and components shall conform to applicable specifications, standards, and patterns as specified herein and Table I. All the materials shall be capable of meeting all the operational and environmental requirements spe
20、cified herein. 3.3.1 Recycled, recovered, or environmentally preferable materials. Recycled, recovered, or environmentally preferable materials should be used to the maximum extent possible, provided that the material meets or exceeds the operational and maintenance requirements, and promotes econom
21、ically advantageous life cycle costs. HFC-227ea materials shall meet the requirements specified in ASTM D6064. Refer to paragraph 6.6. 3.3.2 Pre-Slurry and Post-Slurry Powder Requirements. The SBCSemployed in the preparation of the HFC-227ea/SBCSsuspensions shall be either SBC-1 or SBC-2 as specifie
22、d in the contract or order (see paragraph 6.2). The resulting Agent slurries will be designated either Class I or Class II Agent, respectively. Materials shall not be added to improve the fluidity, appearance, and non-caking characteristics of the SBCS. Note: Only USP grade sodium bicarbonate and ma
23、terials derived by physical processing are acceptable. No chemical additives to the sodium bicarbonate or HFC-227ea are allowed. 3.3.3 Agent chemical and physical requirements. The SBCS(Class I or Class II) moisture content, color, aspect ratio, surface area, size requirement and size distribution,
24、shall be as specified in Table I and verified in accordance with 4.5.1, 4.5.2, 4.5.5, 4.5.6, 4.5.7, and 4.5.8. The agents caking and lumping tendency, flow, suspendability and concentration shall be as specified in Table I and verified in accordance with 4.5.1, 4.5.3, 4.5.4 and 4.5.9. Provided by IH
25、SNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-32412 4 TABLE I. Agent Chemical and Physical Requirements Requirement Class I Agent (contains SBC-1) Class II Agent (contains SBC-2) Value Verification Paragraph Value Verification Paragraph Moisture Content
26、of filtered slurry, maximum ppm 70% suspendability 4.5.4 95% suspendability 4.5.4 Color Natural 4.5.1 Sample readings equal to or above the ICS are reported as 1%. Also report the actual concentration from the calibration curve for reference purposes. A.7 REFERENCES A.7.1 Operating Manuals, Volumes
27、1 3, HP 6890 Series Gas Chromatograph, Hewlett Packard Company, Revision 1, October 1996. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-32412 APPENDIX A 20 A.7.2 Galbraith Laboratories Inc., Standard Operating Procedure, GC-100D Analysis of
28、 Residual Solvents by Gas Chromatography Using Direct Injection and Flame Ionization Detection, Revision 10, June 2011. A.7.3 Williams and Lawton, Drying of Organic Solvents: Quantitative Evaluation of the Efficiency of Several Desiccants, J.Org. Chem., 2010, 75(24) pp 8351-4. A.8 ALTERNATIVE METHOD
29、 for ANALYSIS of WATER in SODIUM BICARBONATE A.8.1 Should the GC method not be available, an alternate, more expensive and more complicated procedure is listed in the following: Karl Fischer based water content determination method: Determination of Moisture in Sodium Bicarbonate, L. N. Gard, R. C.
30、Butler, Anal. Chem., 1954, 26 (8), pp 13671368 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-32412 APPENDIX B 21 PROCESSING of JET-MILLED SODIUM BICARBONATE and HFC-227ea into a SLURRY B.1 SCOPE B.1.1 Scope. This procedure was prepared for
31、the US Army Aberdeen Proving Ground, to produce a slurry of the Class I Agent. A Class I Agent slurry is the mixture of HFC-227ea and SBC-1. Before the slurry is mixed, the SBC-1 needs to be jet-milled to the micron particle size and, in a separate process, mixed “blended“ with the HFC-227ea. B.1.2
32、Applicability. The requirements specified in this appendix are required to meet Class I specifications (Table I). However, while this size reduction method was developed for the purpose of this Appendix other equivalent size reduction processes may exist. The purpose of this procedure is to describe
33、 a method for producing a slurry of HFC-227ea and SBC-1 where the SBC-1 is jet-milled to the micron particle size and is then blended with the HFC-227ea to produce a slurry of SBCSsuspended in HFC-227ea that will be used in fire extinguishing hardware. The procedure defines the reagents and equipmen
34、t required for executing the method, the steps for carrying out the analysis, the controls for insuring quality of the results, and the calculation and reporting requirements. B.2 APPLICABLE DOCUMENTS: (Not Applicable) B.3 REQUIREMENTS B.3.1 Test procedure. B.3.1.1 Jet-Milling of Sodium Bicarbonate
35、to prepare SBC-1. Start with USP grade sodium bicarbonate. Table B-I contains the parameters used to make the jet-milled material SBC-1. Figure B-1 shows a photograph of the jet-milling equipment employed. Table B-II shows the difference in particle size distributions between the feed material and t
36、he processed material for one of the batches. The values given are weight by material volume. The particle size measurement instrumentation used was a Malvern Mastersizer 2000. The particle size values listed in Table B-II were obtained from the Malvern Mastersizer and are not required - they are pr
37、ovided for reference only. B.3.1.2 Processing Equipment. Table B-III contains a list of the processing equipment used to process the jet-milled sodium bicarbonate and HFC-227ea into a slurry. The equipment is assembled using chemical resistant build-your-own hoses according to Figure B-2. Provided b
38、y IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-32412 APPENDIX B 22 TABLE B-I Parameters used to jet-mill the sodium bicarbonate. (for reference only) PARAMETER VALUE Micronizer Size/Type 8” Open Manifold Liner Type Stainless Steel Total Air Flow 130 S
39、cfm 100 Psig, dry nitrogen Grind Pressure 105 Psi Feed Pressure 80 Psi Venturi Throat Dia. 1/4” Dia. Al. Oxide Feed Nozzle Dia. # 30 Vortex Finder Dia. 2.0” Diameter Feeder Type/Size K-Tron Twin / 35 mm Feeder Setting Std. CC Screws / 70 - L Feed Rate 2 lbs/hr. FIGURE B-1. Photograph of jet-milling
40、equipment. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-32412 APPENDIX B 23 TABLE B-II. SBC-1 Particle size distribution (for reference only). FEED PROCESSED d10 = 39.09m d10 = .665m d50 = 78.94m d50 = 1.421m d90 = 139.95m d90 = 2.805m d10
41、0 = 208.93m d100 = 5.754m TABLE B-III. Slurry Processing Equipment. MANUFACTURER/SUPPLIER SPECIFICATIONS De Dietrich 20 gallon reactor, steel, glass lined Corken D91 vapor compressor Q Sonica 700 Watt Sonicator Q Sonica 400 ml high continuous flow flocell Warren Rupp S05 stainless steel diaphragm pu
42、mp Edwards E2M2 vacuum pump McMaster Carr Flat-Panel Open-Tank Heat Exchanger, 316L stainless steel Worthington Cylinders 239 lb refrigerant recovery cylinder Mixer Direct 1/2 HP Flange Mount Gear Driven Variable Speed Mixer w/ 6” Propeller Provided by IHSNot for ResaleNo reproduction or networking
43、permitted without license from IHS-,-,-MIL-DTL-32412 APPENDIX B 24 Storage Tank(Refrigerant Recovery Cylinder)HFC-227ea CylinderSonicatorReactorVacuum PumpDiaphragm PumpAir CompressorControl PanelRefrigerant CompressorHeat ExchangerFIGURE B-2. Slurry processing setup. B.3.1.3 Filling the Reactor wit
44、h SBC-1 and HFC-227ea. Ensure all the reactor valves are closed prior to adding the SBC-1. Weigh 4276 grams of SBC-1 and transfer it into the Reactor through the view port. Close the view port and attach the clamps, such that, the view port is flush with the reactor and the vapor is not allowed to e
45、scape into the Reactor. Set the HFC-227ea cylinder onto the scale and tare the scale. Open the liquid valve on the HFC-227ea cylinder and the valve to the Reactor. Using the diaphragm pump, pump 179 pounds of HFC-227ea into the reactor. Turn off the diaphragm pump and close the reactor valve. A phot
46、ograph of the Reactor is shown in Figure B-3. B.3.1.4 Initial Break-Up of Sodium Bicarbonate at the Bottom of the Tank. Use the compressor to pump HFC-227ea vapor through the bottom of the reactor and break up the SBC-1 that has settled. Allow the compressor to pump through the bottom for one minute
47、. As the vapor is being pumped through, turn on the stirrer and begin mixing the slurry. Turn off the compressor and close the valves while continuing to run the mixer. Figure B-4 shows a photograph of the compressor. Provided by IHSNot for ResaleNo reproduction or networking permitted without licen
48、se from IHS-,-,-MIL-DTL-32412 APPENDIX B 25 FIGURE B-3. Photograph of Reactor. FIGURE B-4. Photograph of the compressor. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-32412 APPENDIX B 26 B.3.1.5 Sonication. Use the diaphragm pump to pump the slurry through the flocell. As the slurry flows through the flocell, turn on the sonicator system and begin sonication. Monitor the wattage and power on the sonication system throughout the process. The target wattage is 200 W. The sonicator should be cycled o
