1、Ia71a8a151a71a71NILITARY SPECIFICATIONNIL-D-3716B28 September 1987SUPERSEDINGNIL-D-3716A22 December 1959(See 6.9)DESICCANTS a71 ACTIVATSD FOR OYNANICDEHUNIOIFICATIONThis specification is approved for use by all Departments and Agencies ofthe Department of Defense.1. SCOPE1.1 -. This specification co
2、vers desiccants that remove a75oisture fromair , other gases, and from 1iquids by dynamic means and that offer an approximateindication of the relative humidity of an enclosed space.1.2 Classification. Desiccants shall be provided in the following typesand grades, as specified (see 6.2. 1):Type I -
3、Large particle size.Grade H - High adsorption capacity.Grade M - Nedium adsorption capacity.Grade L - Low adsorption capacity.Npe II - Medium particle size.Grade H - High adsorption capacity.Grade M - Nedium adsorption capacity.pe IV - Nedium particle size impregnatedGrade H - High adsorption capaci
4、ty.with a humidity indicator.Beneficial comments (recommendations, additions”, deletions ) and any part inentdata which a75ay be of use in improving this documant should be addressed to:Commander, Naval Sea System+ Command, SEA 55Z3, Department of the Navy,Washington, DC 20362-5101 by using the self
5、-addressed Stmdardization Dc.cumrmtImprovement Proposal (DD Form 1426) appearing at the end of this documentor by letter.A17SC NfADISTRIBUTION STATSNSNT A Approved for public release;IFSC 6S50distribution unl f.mited. .Provided by IHSNot for ResaleNo reproduction or networking permitted without lice
6、nse from IHS-,-,-NIL-D-3716D1I2. APPLICABLE f)OCUNENTS2.1 Government documents.2.1.1 Specifications and standards. The following specifications andstandards form a part of this specification to the extent specified herein.Unless otherwise specified, the issues of these documents shall be those liste
7、din the issue of the Department of Defense Index of Specifications and Standards(DoDISS) end supplement thereto, cited in the solicitation.SPECIFICATIONSFEDERALQQ-B-639RR-S-366IT-E-485PPP-B-601PPP-B-621PPP-C-96PPP-D-705STANDARDSFEDERALFED-STD-313MILITARYMIL-STD-105MIL-STD-129MIL-STD-147- Brass, Nava
8、l: Flat Products (Plate, Bar, Sheet,and Strip).- Sieve, Test.- Enamel, Semigloss Rust -Inhibit ing.- Boxes, Wood, Cleated-Plywood.- Boxes, Wood, Nailed and Lock-Corner.- Cans, fetal,28 Gase and Lighter.- Drum, Shipping and Storage: Steel, 16 and 30Gal lon Capecit y.- Naterial gafety Data Sheets Prep
9、aration and theSubmiss ion of.- Sampling Procedures and Tab les for Inspection byAttributes.- Marking for Shipment and Storage.- Pallatized Unit Leads.NIL-STO-11B6 - Cushioning, Anchoring, Bracing, Blocking, andWaterproof ins, uith Appropriate Test Methods.MS16188 - Cbert, Humidity Indicator Color C
10、omparison.MS20003 - Indicator, Humidity, Card, Three Spot, ImpregnatedArees (Cobaltous Chloride).2.1.2 Other Government documents. The following other Governnmnt documenteform e part of this specification to the extmnt specified herein. Unlessotherwise specified, the issues shell be those in effect
11、on the date of thesolicitation.CODE OF FEDERAL REGULATIONS49 CFR 171-195 - Rules and Regulations for Transportation ofExplosives and Other Dangerous Articles.29 CFR 1910.1200 - Hazard Communication Standard.(Tho Code of Federal Regulations is available from the Superintendent ofDocuments, U.S. Gover
12、nment Printing Off ice, Washington, DC 20402. ) a71I2 . .-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-7.a71NIL-D- 3716B(Copies of specifications, standards, and other Government documentsrequired by contractors in connection with specific acquisi
13、tion functionsshould be obtained from the contracting activity or as directed by the con-tracting activity. )2.2 Other publications. The following documents form a part of thisspecification to the extent specified herein. Unless otherwise specified, theissues of the documents which are DoD adopted s
14、hall be those listed in theissue of the DoDISS specified in the solicitation. Unless otherwise specified,the issues of documents not listed in the DoOISS shall be the issue of thenongovernmant documents which is current on tbe date of the solicitation.ANERICAN SOCIETY FOR TSSTING ANO MATSRIALS (ASI?
15、I)A 568 - Standard Specification for Steel, Sheet, Carbon, and High-Strength, LOW-Alloy, Hot-Rolled and Cold-Rolled, GeneralRequirements for. (DOD adopted)B 90 - Standard Specification for Nagnesium-Alloy Sheet and Plate.(DoD adopted)B 209 - Standard Specification for Aluminum and Aluminum-Alloy She
16、ettind Plate. (DoD adopted)(Application for copies should be addressed to the American Society forTasting and Mate= it+ls, 1916 Race Street, Philadelphia, PA 19103. )(Nongovernment standards and other publications are normally availablefrom the organizations which prepare or which distribute the doc
17、uments . Thesedocuments also may be available in or thro”gb libraries or other informationalservices. )2.3 Order of precedence. In the event of a conflict between the text ofthis specification and the references cited herein (except for associated detailspecifications, specification sheets or NS sta
18、ndards) , the text of this spe.ci-ficat ion shal 1 take precedence. Nothing in this specification, how each filled container shall also beweighed to determine th.a amount of contents. Any container in tbe sample havingone or more defects or under required fill, shall be rejected, and if the numberof
19、 defective containers in any sample exceeds the acceptance number for appro-priate sampling in accordance with 1IL-STD-105, the lot represented by thesample shall be rejected.4.6 Tests. Samples shall be subjacted to all of the t“ests as specifiedin 4.7, except the corrosiveness tests and the water v
20、apor adsorption capacitytest for 40, 60, and 80 percent.4.6.1 Retests. If, in the opinion of the contractor, failure of a portionof a sample to conform to this specification was caused by faulty test a75ethods ordamaga to the test sample, the test shall be repeated on the other two portionsof the sa
21、mple. If anv two of the three oortions of a snumle are found t.a b.nonconf orm-tig, tbe .mire sample4.7 Test procedures. Testthrough 4.7.7.4.7.1 Apparent density. Acylinder shall be weighed to theto approximately the 100-mL a75ark. . . _shall b: rejected.procedures shall be in accordance with 4.7.1c
22、lean dry 100-milliliter (mL) , graduatadnearest O.1 gram. The cylinder shall be filledwith act ivated desiccant and shal 1 be weizhedagain. The cyl-tider shall be firmly tapped on a resilient surface, such a;heavy sheet rubber, until tbe volume of desiccant remains constant between twosuccess ive 1-
23、minute tapping periods. The apparent dens ity shall be calculatedby the following formula:Apparent dens ity (pounds per cubic foot) = Weight of das iccant (grams ) x 62.45Volume of desiccant (mL)4.7.2 Water vapa r adsorption capacity. Water vapor adsorption capacityshall be in accordance with 4.7 .2
24、.1 through 4.7.2.2.7Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-_MIL-D-3716B4.7.2.1 Apparatus , The general arrangement of the apparatus shall be asshown on figure 1. The fitting comprising the inlet, outlet, and petticoatbubbler for each saturat
25、or bottle shall have a ground glass stopper to fit thebottle. Tho saturator bottle and bubbler shall be so configured that with 1liter (L) of solution in the bottle the upper holes of the bubbler shall be notmore than 3 inches, nor less than 1 inch below thn surface of the liquid. Eachof the six sat
26、uratnr bottles shall be filled with 1 L of identical sulfuricacid solutions to give the required nominal relative humidity at 25 degreesCelsius (“c) . Table V shows the solutions to be used for this purpose. TIIesample-containing bottle shall be a Nesbitt, Fleming or other standard form ofadsorption
27、 bulb. The bulb shall be provided with a closure to prevent diffusion.The room in which the tests are being run shall be controlled to 25 * 1C.The temperature variation within the saturator bottles, the inlet air and thesample-containing bottle during any one run shall vary by nnt more than plus orm
28、inus O.5C. A desiccant trap filled with activated desiccant under test shallbe placed in front of the saturator bottles to pick up any adsorptive impuritiesin the inlet air.TABLE V. Relative humidity solutiOm. 1Percent by R.H. percent Sp.3cific gravityz Specific gravityzSolution weight at 25C 20C/40
29、C 77F/600FH2S0, 64.61 10 1.5499 1.5462,so. 58.21 1.4789 1.4754,2s0, 47,85 : 1.3739 1.3715HzSo*38.36 60 1.2889 1.2859HzSo*26.23 80 1.1894 1.18581 This table has been computed on the basis of values for tbe specific gravityfound in the International Critical Tables. The nominal relative humiditiesrepr
30、esent values that would be obtained in a closed static system. Theectuel effluent relative humidities generally will be slightly belcw thesenominal values.a Specific gravity measurements should be a75ade at either indicated temperatureusing a precision hydrometer with a smallest subdivision of 0.000
31、5. Thespecific gravity of the sulfuric acid solution should be checked prior toeach determination since the acid-water ratio will change during the courseof detmnnimt ion.4.7.2.2 Procedure. A 6- to 10-gram sample of the desiccant shall beweighed to the neerest a75illigram in the tared adsorption bul
32、b. Extreme careshell be exercised to ensure that the a75aterial is exposed to the air for aminimum time. The adsorption bulb shall than be connected to the apparatus andthe airflow adjusted to 4 * 0.5 L per minute with the bypass closed. If themanometer indicat.as the pressure in the last bottle to
33、be greater than l-inchmercury, tho bleed-off 1ine shal 1 then be cracked open until the a75anometerindicates less than 1 inch and that point a75aintained for the balance of the run.When ueing the bypass en occasional check shall be mede of the amount of airpassing through the adsorption bulb by dive
34、rting tbe bypass air from the flow-meter to atmosphere through the “T” connection. The flowmetor reading wil 1 thenindicate the actual airf lnw through the adsorption bulb. Periodical ly theedsorpt ion bulb shal 1 be removed from the train, stopcocks closed, and the bulb8Provided by IHSNot for Resal
35、eNo reproduction or networking permitted without license from IHS-,-,-IIItlIL-D-3716Ba71 weighed. This process shall be repeated until two successive weighings,approximate lY 1 hour apart, show a weight variation not exceeding O.1 percent;however, the test shall be considered complete if at any time
36、 the a75inimum speci -ficat ion values are attained. Generally, it will be found that the weight willrise to a maximum and then decrease slightly before approaching a constant value.The moisture adsorption capacity shall be calculated from the following equation:.Moisture adsorption capacity, percen
37、t = 100 x wf - -Now - we0Where:W = Final weight of adsorption bulb.W. = Original weight of bulb and sample.We = Weight of empty bulb.4.7.3 Particle size. Particle size shall be determined .in accordance with4.7.3.1 through 4.7.3.2.4.7.3.1 Apparatus . The mechanica 1 shaker to be employed in conducti
38、ngthe particle size test shall operate with a single eccentric circular motionat 285 i 10 revolutions per minute (r/rein) and with a tapping action of 150* 5 strokes per minute to obtain dependable sieve analyses. To permit flexibleoperation, the shaker shall accommodate one to six 8-inch sieves wit
39、h onepan and cover. For ease of operation and reproducibility of sizing tests,an automatic electric time switch is desired.a714.7.3.2 Procsdure. The sieves shall be nested in order of decreasingsizes with the largest sieve cm top and a pan at the bottom. A smph ofaPPrOxatelY 150 grs Of the a75ateria
40、l shall be weighed and shall be placedon the top sieve of tha riest. The nest of sieves with the cover shall be placedin the testing machine and shall be vibrated for 3 a75inutes i 3 seconds with thetapper in operation. It shall be weighed accurately to within O.1 gram, andthe percentage of desiccan
41、t retained on each sieve shall be calculated imme-diately following the shakar operation. Tbe sum of 811 individually retainedweights shall be used as the total weight of the sample.4.7.4 Particle strength. Particle strength shall be determined in accor-dance with 4.7.4.1 through 4.7.4.2.1.4.7.4.1 A
42、pparatus. The apparatus shall be the same as specified in 4.7.3.1.4.7.4.2 Procedure. Procedures shall be as follows:4.7.4 .2.1 Type 1, grade H, M and L; type II, grade H and H; and type IV,grade H. Thoroughly mix all a75aterial retained on tbe no. 18 and coarser sievesin accordance with SR-S-366, as
43、 specified in 4.7.3.2. Weigh a sample to approxi -a75ately 50 grams. Place the smnple on the no. 18 sieve together with five copperdisks (of tba size and weight of l-cent piec), backing the sieve with a no. 30 .Bieve and retafning pan; Shake the sample in the apparatus for 15 minutes.Immediate y fol
44、lowing conclusion of the specified shaker operation tima, reportthe percentage of the des fccant pass ing through the no. 30 sieve which is deter-0mined by accurate weighing to within O.2 gram. Use the sum of the individ-ually retained weights as the total weight of the sample.9Provided by IHSNot fo
45、r ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-D-3716B4.7.5 LOss-on-ignf.tion. Two to 4 grams of the sample of the materialshall be accurately weighed, and immediately transferred to a silica crucible.The crucible (with a cover lid) shall be placed in a cool electr
46、ic furnace. a71Tbo temperature shall be allowed to rise to 960 t 20”C in approximately 1 hour.The cover lid shal 1 be rnmoved. The crucible shall be heated for 1/2 to 3/4hour at that temparaturo. The crucible shal 1 be removed from the furnace andplaced in a desiccator to cool before weighing. Tho l
47、oss-on-ignition shall becolculnted as follows:Las-on-ignition percent = Loss in weight x 100Sample weight4.7.6 Corrosiveness type 1, grades U, M, and L; type II, grades H and M.Corrosiveness shall be determined as follows: Grind 20 grams of the desiccant,retaining that portion that pesses a U.S. no.
48、 40 sieve and is held on a U.S.no. 80 sievo in accordance with RR-S-366. Place this 40 to 80 mesh material ino desiccator maintained at 25C and 60 percent relative humidity by sulfuric.acid solutions (see table V) for a minimum of 24 hours. Prepare a 2 by l/8-inchspecimen of hot rolled steel in acco
49、rdance with ASTM A 568, magnesium in accor-dance with ASTN B 90, bress in accordance with QQ-B-639, and aluminum in accor-dance with ASTN B 209, by grinding and polishing one surface to 6 to 8 rootmean square microinches. Clean the panel of each a75etel by successive traatmantswith :(a) Hot tolu.ne 100”C (212”F) 2-minute immersion.(b) Hot acetone 50”C (120”F) quick rinse.(c) Hot methanol 50C (120”F) quick rinse.During and after cleaning, handle tho
