1、Designation:F31007(Reapproved 2012)Standard Practice forSampling Cryogenic Aerospace Fluids1This standard is issued under the fixed designation F310;the number immediately following the designation indicates the year of originaladoption or,in the case of revision,the year of last revision.Anumber in
2、 parentheses indicates the year of last reapproval.Asuperscriptepsilon()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.Scope1.1 This practice describes procedures for taking a sampleof cryogenic a
3、erospace fluid for analysis.1.2 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory requirements pr
4、ior to use.For hazardstatement,see Section 5.2.Referenced Documents2.1 ASTM Standards:2F311 Practice for Processing Aerospace Liquid Samples forParticulate Contamination Analysis Using Membrane Fil-tersG93 Practice for Cleaning Methods and Cleanliness Levelsfor Material and Equipment Used in Oxygen-
5、EnrichedEnvironmentsG127 Guide for the Selection of Cleaning Agents for Oxy-gen Systems3.Summary of Practice3.1 Dewar Flask ProcedureA clean Dewar Flask is usedto collect a sample of cryogenic aerospace fluid either from asampling valve,or poured from a larger Dewar flask used forstorage.3.2 Cryogen
6、ic Sampler ProcedureThe sampler is used towithdraw a small amount of liquefied gas from a large supply.The sampler is allowed to cool until a steady stream ofcryogenic liquid exists in the sampler.Once the samplingvalves are closed the trapped liquid will convert to a gas andpressurize the sampling
7、vessel.4.Apparatus and Materials4.1 Apparatus and Materials Common to Both Procedures:4.1.1 Protective Clothing,such as an apron,face-shield,andthermal gloves.Coveralls meeting safety requirements forstatic dissipation,and flammability may be required dependingon local safety regulations or operatin
8、g procedures.Whitecoveralls are recommended while working with cryogenicoxygen as they will show dirt or oil which may react violentlywith cryogenic oxygen.4.1.2 Wash Bottle,1L made of a material compatible withthe solvent selected for the cleaning procedure,Teflon FEP isgenerally acceptable with th
9、e solvents and fluids used.4.1.3 Solventsmust be selected to meet the performance,safety,cleanliness,and environmental requirements based onstandardized procedures,local and international environmentalregulations,and local procedures.4.1.3.1 Cleaning Solvents for Cryogenic Oxygen SamplingEquipmentSo
10、lvents for use on oxygen sampling equipmentshould be selected in accordance with 5.6.Examples ofsolvents currently used for this purpose include,but are notlimited to:Hydrofluorochlorocarbons,such as Asahiklin AK 225,Hydrofluorocarbons,such as DuPont Vertrel XF or VertrelMCA,Hydrofluoroethers,such a
11、s 3M HFE 7100 or HFE 71DE,Water-based solvents,such as non-ionic detergents.4.1.3.2 Cleaning Solvent for Sampling Equipment Used withother Cryogenic Fluids:Ethyl acetate shall have no more than 1 g/mLresidue afterevaporation,Cyclohexane shall have no more than 1 g/mLresidue afterevaporation,The clea
12、ning solvent will be an azeotrope mixture of ethylacetate and cyclohexane,filtered in accordance with PracticeF311.The mole fraction axeotropic mixture is 0.5286 ethylacetate and 0.4714 cyclohexane.This is prepared by mixing503 mL of ethyl acetate with 497 mL of cyclohexane toproduce 1 L of cleaning
13、 solvent.A fluorocarbon wash bottleshould be used with this cleaning solvent.4.2 Dewar Flask Procedure:4.2.1 Dewar Flask,1-L capacity.4.2.2 Dewar Cover,with provisions for venting.1This practice is under the jurisdiction of ASTM Committee E21 on SpaceSimulation and Applications of Space Technology a
14、nd is the direct responsibility ofSubcommittee E21.05 on Contamination.Current edition approved Nov.1,2012.Published November 2012.Originallyapproved in 1970.Last previous edition approved in 2007 as F310 07.DOI:10.1520/F0310-07R12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,o
15、rcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.2.3 Stainless Steel Ca
16、tch Bucket(hydrocarbon clean ifused for liquid oxygen sampling).4.2.4 Tongs,stainless steel(Type 300).4.2.5 Carrying Case for flask.4.2.6 Polychlorotrifluoroethylene Bag.4.3 Cryogenic Sampler Procedure:4.3.1 Liquid Cryogenic Samplers34.3.2 Miscellaneous Fittings,for adapting to the samplepoint.4.3.3 Flexible Hose,pressure-rated at 3500 kPa(500 psig)gage suitable for the minimum temperature to be encounteredand made of materials compatible with the fluid being sampled.4.3.4 Handtools,needed to ma
