1、,. MIL-P-28766 55 = 7777906 0235q67 3 MIL-P-28766(EC) 26 February 1971 MILITARY SPECIFICATION POLES, STRUCTURXL WOODEN, FOR HIGH FREQUENCY (HF) ANTENNAS 1. SCOPE 1.1 Scope. This specification covers wooden poles used as structural supports or members for HF antennas, when used in conjunction with a
2、detailed antenna specification. 2. XPPLICABLE DOCUMEILTS 2.1 The following documents of the issue in effect on date of invitation for bids or request for proposal, form a part of the specification to the extent specified herein. SPECIFIC XTIOTU hl1 LIT-ARY MIL-P-14527 - Pole Line Hardware, Packaging
3、 of STAND-IRDS MILIT-ARY hIIL-STD-IO9 - Quality Assurance Terms and Definitions NIL-STD- 129 - Marking for Shipment and Storage (Copies of specificatioiis, standards, drawiiigs, and Imblications required by suppliers in connection with specific procurement fii!ictioiis sliould be obtained from the p
4、rocuring activity.or as directed by the con- tracting officer.) 2.2 Other publications. The following documents form a part of this specification to the extent specified herein. Unless otherwise indicated, the issue in effect 01 date of invitation for bids or request for proposal shall apply: 05.1-1
5、 963 Wood Poles, Specifications and Diminsions for i ! (.ipplication for copies should be addressed to the ANSI 1430 Broadway, New York, Xew York 10018.) AMERICAN WOOD PRESERVERS ASSOCIATION (AWPA) C1 - =u1 Timber Products Preservative Treatment by Pressure Processes C4 - Poles Preservative Treatmen
6、t by Pressure Proccsses 311 - Standard for the Purchase of Treated Wood Products M2 - Standard Instructions for the Inspection of Preservative Treatment of Wood P1 - Standard for Creosote (-ipplication for copies should be addressed to the AWPA, 1012 14th St. N.W., Washington, D.C. 20005.) - _- -.C-
7、.L-iir-ri-_ .-LI*-_ /- THIS CUM MENT CONTAINS lo PAGES. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-P-28766 55 9799906 02L5970 T W MIL- P- 28 66( EC) AMERICAIS SOCIETY OF TESTIXG MATERIALS (ASTaI) d3b A153 - Specification for Zinc Coating Hot
8、 Dip) on Iron and Steel Hardware. - Specification for Structural Steel (.Application for copies should be addressed to the ASTM, 1916 Race Street, Philadelphia, _ Pennsylvania 19103.) UMFORAI CLASSIFIC.-TIOK COJMlb ITTEE Uniform Freight Classification Rules (Application for copies should be addresse
9、d to the Uniform Classificat 516 West Jackson Boulevard, Chicago, Illinois 60606.) 3. REQUIREMENTS )n Committee, 202 Union Station, - 3.1 General. Wooden poles shall conforni to the applicable requirements of ANSI 05.1, and shall be Douglas Fir or Southern Pine. 3.2 Physic al requirement s. 3.2.1 Si
10、ze. Unless otherwise specilied in the procurement document (see 6.2), the size of the pole shall be as required to satisfy the structaral requirements of its application, limitations due to the method or route of shipment and shall be a preferred standard size as specified in ANSI Specification 05.1
11、 for the wood selected. Poles of a numerical class higher than 4 shall not be used (see 6.4.1). 3.2.1.1 Length. The length of the pole as measured between its extreme ends shall be at least the length specified iii 3.2.1, (the branded nominal length) but may not exceed this length by more than 6 inc
12、hes. 3.2.1.2 Diameter. The minimum aiid maximum diameters of the butt and top of the pole when calculated from measurements made by means of B circumference tape, shall neither be less than the diameters fixed by its length and class in -ISS1 05.1 for the particular wood selected, (as branded on the
13、 pole) nor shall they exceed those diameters by more than 1 inch. 3.2.2 Limits of imperfection. 3.2.2.1 Seasoning checks. Seasonirg checks of any length are permitted provided that they do not extend in depth beyond the pitch center of the pole. Splits or grain separation which extend from one surfa
14、ce to another are not permitted to extend more than 6 inches along the length of the pole and shall be limited to either butt or top ends. , 3.2.2.2 Crooks. Poles shall be free from short crooks. Any sweep shall be in one plane and one direction only. -I straight line drawn frJm a top edge to a bott
15、om edge of a pole shall, at no point along the pole, fall more than 1 inch for every 10 feet of the pole length from the pole surface. 2.2.2.3 Spiral grain. The spiral grain (twist grain) shall not exceed the following limitations: Length of p,le 30 feet and shorter 30 feet to 45 fezt incl. Maximum
16、Twist of Grain i complete twist in any 10 feet i complete twist in any 16 feet 1 complote twist in any 20 feet SO feet aiid 1ar;jer 3.2.3 Roof. A one-way roof, cut at an angle of 15 to 20 degrees from the horizontal, shall be provided at thc. top of poles. 2 Provided by IHSNot for ResaleNo reproduct
17、ion or networking permitted without license from IHS-,-,-MIL - P - 2 8 7 66( EC ) 3.2.4 Ground line. A ground line that will remain clearly visible up to the time of installation shall be marked on each pole. The ground line shall be so related to the radiating curtain and guy fastening positions as
18、 to assure maintenance of the electrical and mechanical characteristics of the antenna when the pole is buried to the ground line depth when installed on a level ground plane. cabie requirements of :1WPA standards C1, C4 and M1. Air seasoning is the preferred me?hod of condition- ing whew climatic c
19、onditions and time aise not unfavorable factors. . -.“ t“ 9; $ 8 3.2.5 Conditioning prior to treatment. Prior conditioning shall be provided in accordance with the appli- + 3.2.6 Prcacrvativc treatment. Preservative treatment by full cell pressure process shall be provided in accordance with the app
20、licable requirements of AWPA standards C1 and C4. All possible pole cutting, boring, framing, salving, trimming, marking, branding and making of inserts shall be done prior to pressure preservative treatment. Final steam bath is not permitted. quirements of the -4WP-I standard P1. bd ?.O pnds per cu
21、bic fooffor Southern Pine. 3.2.6.1 Preservative. The preservative shall be a creosote-coal tar. The creosote shall meet the re- 3.2.6.2 Final retention. Final retention shall not be less than 12.0 pounds per cubic foot for Douglas Fir 3.2.7 Marking of poles. Poles shall bear a clear imprint of the t
22、wo marks indicating acceptance by the inspector before and after treatment. 3.2.8 Instructions. Instructions shall be provided for field treatment of any accidental damage, field cutting, or boring which is unavoidable, by soaking the area with a minimum of three applications of hot pre- servative,
23、or in the case of holes, by inserting a plug at one end and a pressure gun at the other, to force the preservative into the wood. The after-treatment preservative and pressure shall be the same as that origi- nally used on the whole member. When specified in the procurement document, kits to accompl
24、ish the above repair shall also be supplied on a per destination basis (see 6.2). Preservative quantities shall be one quart . . per pole supplied. ;$ g; 3.3 Pole line hardware. -. ?:heating or other electrical causes (see 3.6). 6.4.2 Withstand. Withstand is defined as not being consumed, damaged, or destroyed due to dielectric 4 I “I Preparing activity: Navy - EC (Project 551 O-N135) Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
