1、ww-L-2887 9 9999974 0378956 784 W WW-L-2887 20 July 1998 FEDERAL SPECIFICATION TUBE, PHENOLIC, POROUS RETAINER FOR USE IN INSTRUMENT BEARINGS The General Services Administration has authorized the use of this Federal Specification by all Federal agencies. 1. SCOPE 1.1 Scope. This specification cover
2、s basic characteristics required for porous laminated phenolic materials intended for use as instrument and thin section ball bearing retainers (cages), and methods of determining these characteristics. 1.2 Classification. The materials shall be Wshed in the following types and forms as specified (s
3、ee 6.2) TYPE DESCRIPTION FBFW Rolled tube made fiom cotton fabric weighting 4 ounceshquare yard or less with a total thread count of 130 to 176 threads per inch. FBEFW Rolled tube made from cotton fabric weighing 3 ouncedsquare yard or less with a total thread count of 177 to 300 threads per inch. R
4、olled tube made distribution is unlimited. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-WW-L-2887 9999974 0378957 b30 WW-L-2887 2. APPLICABLE DOCUMENTS 2.1 Government publications. The following documents, of the issues in effect on the date of in
5、vitation for bids or request for proposal, form a part of this specification to the extent specified herein. STANDARDS DEPARTMENT OF DEFENSE MIL-STD-129 - Marking for Shipment and Storage (Unless otherwise indicated, copies of the above standard is available from the Standardization Documents Orderi
6、ng Desk, Building 4D, 700 Robbins Avenue, Philadelphia, PA 191 11-5094.) 2.2 Non-Government mblications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues are cited in the solicitation documents. AMERICAN SOCIETY FOR QUALITY C
7、ONTROL (ASQC) ASQCZ1.4 - Sampling Procedures and Tables for Inspection by Attributes (Application for copies should be addressed to American Society for Quality Control 6 1 1 West Wisconsin Avenue, Milwaukee, WI 53 20 1-3 005 .) AMERICAN SOCIETY FOR TESTING AND MATEIUALS (ASTM) ASTM-D 18 - Plastics
8、Conditioning and Electrical Insulating ASTM-D695 - Properties of Compressive Rigid Plastics OD Adopted) ASN-D792 - Density and Specific Gravity (Relative Density) of Plastics by Displacement OD Adopted) ASN-El 1 Sieves, Wire Cloth, for Testing Purposes OD Adopted) Materials for Testing (DoD Adopted)
9、 - (Application for copies should be addressed to the American Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.) 2.3 Order of precedence. In the event of a confiict between the text of this document and the references cited herein, the text of this document
10、 takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-ww-L-2887 m 9999974 0178958 557 rn , WW-L-28 87 3. REQUI
11、REMENTS 3.1 Tubes. The tubes shall consist of base material (reinforcement) as described in 3.3 impregnated and bonded with a non-plasticized phenolic resin. Tubes will be made by passing the impregnated material over heated rolls and winding the heated material onto a mandrel while applying pressur
12、e to the materidmandrel. The overwrapped mandrel is then placed in an oven to cure the tube. 3.2 Base materials. 3.2.1 Cotton fabric. FBFW tubing. FBFW tubing shall be made from cotton fabric weighing 3 to 4 ouncedsquare yard. Finished fabric shall be desized, washed and/or bleached, and remaining e
13、xtractables shall be not greater than 2 percent however, if not possible, other means of producing particles equivalent to drillings may be used. Drillings taken from a large tube shaii be representative of all sections of the tube in equal proportions. The drills for sampling shall be kept sharp so
14、 no extreme heating of the material shall occur during drilling, which will tend to pre-cure the material. 4.5.5.2.2 Obtaining samples. If impracticable to obtain samples by drilling, the parts may be broken up with a lathe, planer, milling machine, or grinder. A mortar and pestle or a pebble mill i
15、s considered a grinder, provided no perceptible heating occurs during the grinding procedure. A sharp file or rasp may be used for procuring the sample where the size or shape of the part is such that there is no other method. 9 Provided by IHSNot for ResaleNo reproduction or networking permitted wi
16、thout license from IHS-,-,-WW-L-2887 = 9999974 OL789b5 797 WW-L-28 87 4.5.5.2.3 Particle size. The particles of the sample shall pass through the No. 40 sieve with minimum reworking or grinding. When preparing the sample, the smallest volume shall be obtained for a unit weight of material. 4.5.5.2.4
17、 Sample sieving. The sample shall be sieved through a No. 40 sieve and the particles not passing through shall be re-ground and blended with the original material passing through the sieve. After assembling the Nos. 40 and 140 sieves and the receiving pan, the sample shall be placed in the top sieve
18、, covered, and the entire sample shall be re-sieved either by a mechanical sieve shaker or hand sieving. If the hand sieving method is used, the sieve shall be rotated with slight tapping, the period of rotation being 5 minutes. 4.5.5.2.5 Post sieving. After sieving, the sample (that portion which h
19、as passed through the No. 40 sieve and has been retained on the No. 140 sieve) shall be placed immediately in an airtight container to prevent absorption of moisture by the powder and any consequent error as a result. 4.5.5.3 Conditioning Condition the test specimens at 23 f 2C (73 k 4F) and 50 f 5
20、percent relative humidity for not less than 40 hours prior to testing in accordance with Procedure A of ASTM D6 18 for those tests where conditioning is required. 4.5.5.3.1 Test conditions. Conduct tests in a standard laboratory atmosphere of 23 f 2C (73 f 4F) and 50 rt 5 percent relative humidity,
21、unless otherwise specified in the test methods or in this specification. 4.5.5.4 Procedure. 4.5.5.4.1 Extraction. The extraction procedure shall be carried out in triplicate. Weigh a 3 .OOO-gm portion of the powered sample into a tared, acid-hardened, open-texture quantitative filter paper, 12.5 to
22、15 cm in diameteqor into a standard, single-thickness extraction thimble, 80 by 22 mm, trimmed if necessary. Mer folding over, the thimble or filter paper desiccator is ready to insert in the siphon. 4.5.5.4.2 Siphoning. Press the filter paper or thimble containing the weighed sample into the siphon
23、 such that the outlet at the bottom is not plugged. Place the condenser and the siphon in the extraction tube and add 50 mi of cp acetone. Start the water through the condenser and adjust the heat (If an oil water bath is used for heating, the height of the liquid in the bath should not come above 2
24、.5 cm (1 inch) below the highest level of the acetone in the siphon before the siphon starts to discharge.) so that the siphon fills and empties between 15 and 20 timeshour. This rate shall be careflly maintained, and the sample shall be extracted for 4 hours. After the siphon empties, remove the fl
25、ask and pour the contents into an individually weighed dish. Wash the flask three times with the smallest possible quantity of acetone, using a wash bottle, and add the washings to the extracted liquid in the dish. 10 Provided by IHSNot for ResaleNo reproduction or networking permitted without licen
26、se from IHS-,-,-WW-L-2 8 87 4.5.5.4.3 Drying. Place the dish in a well-ventilated drying chamber, maintained at 50 f 2C (It is very important that the specified temperature be maintained, othemise consistent results cannot be obtained between different laboratories. An electrically heated oven shoul
27、d not be used unless it is exceedingly well ventilated, as the acetone fumes are likely to come in contact with the heated coils and cause an explosion.), and dry the sample to constant weight. Between dryings, all dishes containing the residue shall be kept in a desiccator to prevent the absorption
28、 of moisture. 4.5.5.5 Calculation and report. 4.5.5.5.1 Calculation. Calculate the percentage of acetone-extractable matter in the specimen as follows: Acetone-extractable matter, percent = (W - D)/S X 100 Where: W = weight of the dish and extract (gm) D = weight of the dish (gm) and S = weight of t
29、he original sample (gm) 4.5.5.5.2 Report. The report shall include the percentage of acetone-extractable matter for each sample, and the average percentage of acetone-extractable matter for the three samples. 5. PACKAGING 5.1 Packaging. Material to be packaged per vendors accepted standard practice
30、unless detailed requirements are specified in the contract. 5.2 Marking. Shipping containers shall be marked in accordance with MIL-STD-129. 6. NOTES INFORMATION FOR GUIDANCE ONLY. This section contains information of a general or explanatory nature which may be helpful, but is not mandatory. 6.1 In
31、tended use. Materials producd to this specification are intended for use as ball bearing retainers (cages). Temperature range is limited to 250F (117C) and below. 6.2 Orderina data. Procurement documents should spec the following: a. Title, number and date of this specification. b. Type required (se
32、e 1.2). 11 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-WW-L-2887 c. Specific gravity (see 3.4). d. Property values for special size tubes (see table I). e. Dimensions required. f Special marking required (see 5.2). g. Required test data must be r
33、equested at the time the purchase order is submitted and listed on the purchase order. 6.3 Subiect Term kev word) listing. Laminated Plastic, Fabricated CONCLUDING MATERIAI, MILITARY INTEREST custodians Navy - AS Air Force - 84 hpMI Review Activities: hy - AT, AV Navy - CH CIVIL AGENCY COORDINATING ACTIVITIES: GSA-FS S Preparing Activity: OD Project 9330-0003) Navy - AS 12 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
