ASTM_E_1773_-_10.pdf

Designation:E177310Standard Practice forSealing Rigid Wall Tactical Shelters with Polysulfide BasedSealants1This standard is issued under the fixed designation E1773;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()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 covers the procedures for sealing rigidwall tactical shelters.It outlines the techniques for the storage,mixing,handling,and application of polysulfide based seal-ants.1.2 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 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 limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D907 Terminology of AdhesivesE1749 Terminology Relating to Rigid Wall RelocatableShelters2.2 Society of Automotive Engineers(SAE)Specification:3SAE-AMS-S-8802 SealingCompound,Temperature-Resistant,Integral Fuel Tanka and Fuel Cell Cavities,High AdhesionSAE-AMS-3819 Cleaning Cloths3.Terminology3.1 DefinitionsSee Terminology E1749 for definitions ofgeneral terms used in this practice.3.2 Definitions of Terms Specific to This Standard:3.2.1 acceleratorused by sealant formulators to denote aningredient included in the formulation to accelerate the rate ofcure.It is also used separately in a mixture to accelerate surfacecuring only of applied polysulfide sealant,that is,tack free timeaccelerator.3.2.2 adhesionThe state in which two surfaces are heldtogether by interphase forces.D9073.2.3 application time(sealants)the time available forsealant application after mixing or time available after thawinga premixed and frozen cartridge of sealant.3.2.3.1 DiscussionAcceptability limits for Class B extrud-able sealants are expressed in terms of the extrusion rate of asealant from a 6 floz(180 mL)cartridge through a nozzle witha 0.125 in.(3.2 mm)diameter orifice,using air pressure of 906 5 psi(620 6 34 kPa)in a pneumatic sealant gun.Theextrusion rate is expressed in grams per minute or on cc perminute.A minimum extrusion rate after the stated applicationtime is given as the acceptable limit.Sealant applied after theapplication time is exceeded tends not to wet the surface welland thus not to form a good bond.This term should not be usedinterchangeably with work life.3.2.4 assembly timethe amount of time available after atwo-part sealant is mixed,before the faying surfaces,to whichsealant is applied,shall be assembled and the sealant squeezedout.3.2.4.1 DiscussionIf the assembly time is exceeded,thecure will have progressed too far to permit most of the sealantto be squeezed out for the desired surface to surface contact.The term assembly time is used in reference to faying-surfacesealants.Also called work life and open time.3.2.5 base compoundthe major component of a two-partcuring sealant that contains the polysulfide polymer.3.2.6 bridgingsee Terminology E1749.3.2.7 cartridgea plastic container which contains an inte-gral plunger.3.2.7.1 DiscussionThe cartridge is used to contain either afrozen quantity of premixed base compound and curing com-pound or simply the base compound in unmixed injection kits.1This practice is under the jurisdiction of ASTM Committee E06 on Perfor-mance of Buildings and is the direct responsibility of Subcommittee E06.53 onMaterials and Processes for Durable Rigidwall Relocatable Structures.Current edition approved Nov.1,2010.Published December 2010.Originallyapproved in 1995.Last previous edition approved in 2005 as E1773 05.DOI:10.1520/E1773-10.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from SAE International(SAE),400 Commonwealth Dr.,Warrendale,PA 15096-0001,http:/www.sae.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.8 cohesion strength(sealant)the internal forces hold-ing a cured sealant together.3.2.9 contaminantany foreign substance that degrades theperformance of the sealant.3.2.10 cure ratethe rate at which a sealant polymerizes orcrosslinks(that is,solidifies),a measure of which is thehardness of a sealant at a specified cure time.3.2.11 cure time(sealants)the time required for a sealantto polymerize and develop its full physical/mechanical prop-erties.3.2.11.1 Discussi