1、MILITARY SPECIFICATION , MIL-G- 826 82 (OS ) 30 octorber 1978 Superseding (See 6.3) Beneficial comments (recommendations, additions, deletions), and any pertinent data which may be of use in improving this document, should be addressed to: Standardization Division (611), Indian Head, M 20640, by usi
2、ng the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document, or by letter. Commanding Officer, Naval Ordnance Station, GRAPHITE BILLETS, EXTRDH) (FOR HIGH TEMPERATURE APPLICATION) This specification is approved for use by the Naval Sea Sys
3、tems Command, Department of the Navy, and is available for use by all Departments and Agencies of the Department of Defense. . 1. SCOPE 1.1 Scope. This specification covers one type of extruded gr8phita billets for use in high temperature application. 2. APPLICABLE DOCUMENTS 2.1 Issues of documents.
4、 The following documents, of the issue in effect on date of invitation for bids or request for proposal, form a part of this specification to the extent specified herein. STANDARDS MILITARY MIL- S TD- 12 9 DRAWINGS Marking for Shipment and Storage NAVAL SEA SYSTEMS COMMAND (Code Ident. 10001) SA 26a
5、ii5 Specific Resistance Testing Apparatus Assembly (Copies of specifications, standards, drawings, and public8tions required by contractors in codneetion with specific procurement functions should be obtained from the procuring activity or as directed by the contracting officer.) Provided by IHSNot
6、for ResaleNo reproduction or networking permitted without license from IHS-,-,-2.2 Other publications. The fol1owir.g documents form a part of this o specification to the extent specified herein, Unless otherwise indicated, the issue in effect on date of invitation or bids or request for proposal sh
7、all apply, - AMERICAN SOCIETY-FOR TESTING AND MATERIALS (ASTM) ASTM C 78-75 Flexural Strength of Concrete (Using Simple Beam with Third-Point Loading) (Application for copies should be addressed to the American Society for Testing and Materials, 1916 Race Street, Philadelphia, PA 19103.) NATIONAL MO
8、TOR FREIGHT TRAFFIC ASSOCIATION. INC., AGENT National Motor Freight Classificaiion (Application for copies should be addressed to the Associations, Attn: Traffic Department, 1616 P Street, American Trucking Washington, DC 20036.) UNIFORM CLASSIFICATION COMMITTEE, AGENT Uniform Freight Classification
9、 Rules (Application for copies should be addressed to the Uniform Classification Committee, Room 1106, 222 South Riverside Plaza, Chicago, IL 60606.) (Technical society and technical association specifications and standards are generally available for reference from libraries. are also distributed a
10、mong technical groups and using Federal agencies.) They 3. REQUIREXENTS 3.1 Preproduction. Unless otherwise specified in the contract (see 6.2), the contractor shall furnish samples for preproduction inspection and approval (see 4.4, 6.4 and 6.5). - 3.2 Material. The material shall be graphite bille
11、ts of a size specified in the contract (see 6.21, formed by the extrusion process from a petroleum coke having a particle size not greater than .O32 inch. 3.3 Physical properties. The physical properties of the material shall conform to the requirements specified in Table I. 3.4 Identification. The
12、ends of each billet shall be color-coded in white as specified in the contract (see 6.2). be indicated on the cylindrical surface of each billet by an arrow. The grain direction shall 3.5 Workmanship. The graphite shall be manufactured to ensure uniform billets free from visual cracks, contaminants,
13、 or any defects which would prevent its use for the purpose intended. 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NIL-Gr2pLT 96 M 9999906 0419230 2 W MIL-G-82682 (OS) Unit of Measure grams per cubic centimeter (g/cmI Table I. Physical propertie
14、s. VALUE Maximum Minimum 1.64 1.50 Apparent density ohm - centimeters 10-4 1 12.5 - Re sis t ivi ty with grain Flexural strength with grain across grain Ash content O. 33 weight percent (wtX) I - pounds per square inch (psi) 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for inspection. Unless o
15、therwise specified in the contract, the contractor is responsible for the performance of all inspection requirements as specified herein. in the contract, the contractor may use his own or any other facilities suitable for the performance of the inspection requirements specified herein unless disapp
16、roved by the Government. right to perform any of the inspections set forth in the specification where such inspections are deemed necessary to assure that supplies and services conform to prescribed requirements. Except as otherwise specified The Government reserves the 4.2 Classification of inspect
17、ions. The inspection requirements specified herein are classified as follows: a. Preproduction inspection (see 4.4). b. Quality conformance inspection (see 4.5). 4.3 Inspection conditions. Unless otherwise specified (see 6.21, all inspections shall be performed under the following conditions: a. Tem
18、perature: Room ambient 18 to 35OC (65 to 95F) b. Altitude: Normal ground c. Vibration: No requirement d. Humidity: Room ambient to 95 percent, maximum 4.4 Preproduction inspection. When required (see 6.2), a preproduction sample consisting of two billets selected in accordance with 4.5.2 shall be su
19、bjected to the preproduction inspection consisting of the tests and examination of 4.6. Failure to pass any test or examination shall be cause for rejection of the preproduction sample. The preproduction inspection 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without licens
20、e from IHS-,-,-MIL-G-82682 (OS) F shall be performed by the contractor, after award of contract and prior to production, at a location acceptable to the Government. inspection shall be performed on sample billets which have been produced with equipment and procedures normally used in production. app
21、roval is valid only on the contract under which it is granted, unless extended by the Government to other contracts (see 6.4). Preproduction Preproduction 4.5 Quality conformance inspection. The quality conformance inspect- ion shall consist of the tests and examinations of 4.6 performed on samples
22、selected in accordance with 4.5.2. The ash content test of 4.6.5 shall be performed after all other tests have been conducted. Failure of any billet to pass any test or examination shall be cause for rejection of the lot. 4.5.1 g. A lot shall consist of material manufactured during a single producti
23、on run, without change in process, and to be offered for acceptance on one contract at one time. as specified in the contract (see 6.2). The maximum lot size shall be 4.5.2 Sampling. Unless otherwise specified in the contract (see 6.2), the sample billet size shall bqin accordance with Figure 1. All
24、 billets shall be subjected to the visual examination of 4.6.1. percent of the lot, but in no case more than ten or less than 2 billets, shall be randomly selected for destructive testing. Ten 4.5.2.1 Billet specimens. Two 1.50-inch slabs shall be cut across the main from the tor and bottom of each
25、sample billet. Three 1.25 by 1T25 by 7-inch tes; specimens shall be cut-from each slab. the sample diameter is not of sufficient size to obtain a 7-inch specimen, a shorter specimen shall be prepared. material, six test specimens, 1.25 by 1.25 by 7 inches, shall be cut lengthwise with the grain. Whe
26、re From the remaining cylindrical 4.5.2.2 Testing of specimens. Specimens from each billet shall be tested in accordance with the following: a. Randomly select three test specimens for apparent density evaluation. b. C. The six “with grain“ specimens shall be tested for resistivity. Each “across gra
27、in“ and each “with grain“ specimen shall be evaluated for flexural strength. d. Three “with grain“ and three “across grain“ test specimens shall be selected for ash content determination. 4.6 Inspection methods. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license f
28、rom IHS-,-,-P MIL-G-82682 96 W 9799906 0419232 b W MIL-G-82682 (OS) t 4.6.1 Visual examination. Each billet shall be visually examined to verify conformance to the requirements of 3.2, 3.4 and 3.5. 4.6.2 Apparent density. The apparent density shall be determined in accordance with the following proc
29、edure: a. Procedure. Measure each dimension of the test specimen Calculate the volume based on these average dimensions. in three or more places to the nearest millimeter and average each dimension. Weigh to the nearest 0.01 gram(g). and their average. Report a minimum of three determinations b. Cal
30、culation. Apparent density = V Where: M = weight of sample, g V = volume of sample, cubic centimeters (cm3) 4.6.3 Resistivity. Resistivity shall be determined in accordance with either Method A or Method B. shall be determinative. In the case of a dispute, Method A 4.6.3.1 Method A. Method A shall b
31、e performed in accordance with the following equipment and procedure: a. Apparatus: 1. Specific Resistance Testing Apparatus Assembly, SA 2. Leeds and Northrup Potentiometer, - number 7553, or 3. 3.0 volt direct current (Vdc) source 2681115 equivalent b. Procedure: AssembleOthe apparatus as shown on
32、 Figure 2. Balance the potentiometer according to the manufacturers instructions Place a weight of appzoximately 5 pounds on the center of the specimen to ensure contact of the potential points. Determine the current pass through the test specimen. Report a minimum of six determinations and their av
33、erage. c. Calculation: Resistivity (ohm cm) = EA IL 8 Where:. A a cross-sectionai area, square centimeters (cm2) L = length of conductor, cm E = potential difference, V I = current, amperes (A) 4.6.3.2 Method B. Method B shall be performed in accordance with the following equipment and procedure: 5
34、Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-G-82682 96 9999906 O439233 8 G MIL-G-82 682 (OS) a. Apparatus : 1. 2. 3. Low voltage dc power source Weston dc ammeter (range of O to 100) or equivalent Weston dc millivoltmeter (range of O to 100)
35、or equivalent b. Adjust the rheostat to achieve desired current level and determine Procedure. Assemble the apparatus as shown on Figure 3 and bring the current carrying compression heads into tight contact with the stock. the mV drop between points C and D as shown on Figure 3. minimum of six deter
36、minations and their average, Report a c. Calculation. Resistivity (ohm cm) = IL Where: A = cross-sectional area, cm2 L = length of conductor, cm E = potential difference, V I = current, A . 4-6.4 Flexural strength. The flexural strength shall be determined in accordance with ASTM C78-75. 4.6.5 Ash c
37、ontent. The ash content shall be determined in accordance with the following procedure: a. Procedure. Weigh a sample of approximately 10 g, to the nearest 0.1 mg, in a previously ignited, tared 100-TDL platinum crucible. Place the weighed sample in a muffle furnace and heat to a temperature between
38、800 and 900C for 24 hours (to prevent ash-fusion, do not exceed 900OC.) Allow the crucible and sample to cool to room temperature and examine the residue for traces of carbon. If carbon is present, the ignition shall be continued until ashing is complete. Transfer the cool sample to a desiccator and
39、 allow to stand for a minimum of 1 hour before weighing to the nearest 0.1 mg. carbon, repeat the ignition twiCe more for 1-hour periods at 800 to 9O&C until a constant weight is obtained. determinations and their average. When there is no further evidence of Report a minimum of three b. Calculation
40、. Ash content, wt% = ash weight x 100 sample weight 4.7 Packaging, packing and marking inspection. The packaging, Failure to meet any requirement shall be packing and marking shall be inspected to verify conformance to the requirements of section 5. cause for rejection. 5. PACKAGING 5.1 Packaging an
41、d packinq. Unless otherwise specified in the contract (see 6.2), packaging and packing shall be comercial. 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-G-82682 96 = 9999906 OLI39234 T MIL-G-82682 (OS) 5.1.1 Commercial. Unless otherwise speci
42、fied in the contract (see 6.21, packaging and packing of the graphite shall be in accordance with standard commerical practice applicable to the type of material. The packaging and packing shall be of such contruction and materials that the contents will be adequately protected against loss or conta
43、mination. Containers shall conform to Uniform Freight Classification, National Motor Freight Classification or to rules of other carriers applicable to the mode of transportation. 5.2 Marking. In addition to any special marking required by the contract (see 6.21, each container shall be marked in ac
44、cordance with MIL-STD-129. information: Marking shall include, but not be limited to, the following a. b. Manufacturers name and location c. Material trade name d. Net weight and volume e. and date of manufacture f. Storage conditions 8. Contract number Title, number and date of this specification L
45、ot number, batch number(s), billet identification (see 3.4), 6. NOTES 6.1 Intended use. The graphite is intended for use as a rocket nozzle insert material in the Mk 12 missile booster for the standard missle. 6.2 Ordering data. Procurement documents should specify the following: - 6.2.1 Procurement
46、 requirements. a. b. d. e. f. 6.4 and 6.5) g* h. i. j. C. (see 5.1) Title, number and date of this specification Manufacturers grade designation (see 6.6) Quantity required . Place of delivery Maximum lot size (see 4.5.1) When a preproduction sample is not required (see 3.1, 4.4,. Size of billets re
47、quired and color code required (see 3.2 and 3.4) Inspection conditions, if other than as specified (see 4.3) Location of preproduction inspection (see 4.4) Packing and packaging requirements, if other than as specified 6.2.2 Contract data requirements. Any data required for delivery in connection wi
48、th this document shall be specified on a DD Form 1423 incorpor- ated into the contract. Such data will be delivered as identified on completed (numbered) DIDs (Data Item Descriptions/DD Form 1664) which will be documented in the Applicable ADL (Authorized Data List). 7 Provided by IHSNot for ResaleN
49、o reproduction or networking permitted without license from IHS-,-,-MIL-G-82682 (OS) 6.3 Supersession information. MIL-G-82682 includes the requirements z of and supersedes Naval Sea Systems Command (Code Ident 10001) purchase description WS 2516A, dated 1 May 1967. a 6.4 Preproduction sample waiver. Preproduction samples submitted and approved on a recent contract may be accepted by the procuring activity in lieu of an additio
