1、24 April i970 SuPpImm MIL-T-20705 30 Docember i957 IETB, SCBRIPIER, BACK-RIP This specification is mandatory for use by all Departments an8 Agencies of the Departnuent of Defense. 1.1 Scope. This specification covers teeth for back-rip ucarifiers for tractors equipped with dozer bhdes which permit p
2、enetrating end ripping the ground when the tractor is traveling in reverm gear only. The teeth are suitable for operation ia ail types of terrain whem rugged and hgh-strength parts are reqriired. 1.2 Claasification. Tooth sizes cormapond to te size of shank on which they are mounted, a8 shown in tab
3、le I. Feeth shall be Ykrnished in the sizes specified: Table I. Tooth sizes Tractor rawbar puU Tooth size Shank thiCkn Teat Methoda. STD. NO. 151 Military MIL-STD-O HIL-srpD-ll86 m3m 339126 m39333 - Sampling Procedures m Tables for inspection by Attributes . - Marking for Shipment m Storage. - Ident
4、ification Marking of U. 8. - Cushioning, Anchoring, Bracing, Blookhg, and Waterpmofiag; with Appropriate Test Methods. - Shaak, Scarifier, Baok-Ripj Bulldozer . - Shanic, Scarifier, Back-Rip, Angledozer. Tooth, Surface Ripping, Back-Rip. Nilitary Property. (Copies of specifications and standards req
5、uired by suppliers in connection with specific procurenent functions should be obtained fromthe proawbg mtLvity or as directed by the contracting officer . ) this specification to the extent specified herein. Unless otherwise 2.2 Other p#lrlications. The foUowlng documents form a part of 2 Provided
6、by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-T -20705 indicated, the issue in effect on date of invitation for bids or request for proposal SU apply. Standard Qualification Procedure (AWS B3 .O) (Application for copies shoud be addressed to the Anmican
7、 Welding Society, 345 East 47th Street, New York, PT. Y, 10017.) Boiler and Pressure Vessel Code Section Sc, Welding Qualifications. (Application for copies should be addressed to the American Society of Mechanical Engineers, 345 East 47th Street, Hew York, 1. Y. 10017.) National bbtor Freight Class
8、ification. (Application for copie8 should be addressed to the American Trucking Associations, Inc., ATPN: Street NW, Washington, D. C. 20036.) Tariff Order Section, 1616 P Wnifonn Freight Classification. (Application for copies should be addressed to the Tariff niblishing Officer, Room 202, Union St
9、ation, 516 West Jackson Boulevard, Chicag, fllinoio 60606.) 3.1 Description. !Phe back-rip scarifier teeth shall be of the replaceable, positive lock-on type and shall be used on baak-rip sckifier shanks which conform to S39000 and M539126. 3.2 b2aterial. The working surface of the tooth shall be a
10、chromium-mlybdenagi (Fs 4100-series) or a nickel-chromium-molybdenum 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-T-20705A. P (Fs 430-, FS %W-, FS 8?-, or IS g00-series) steel conforming to m-S=624, The working surface of the tooth shall be
11、heat treated to a.hardness of 415 to 495 Brimel, The body or parts of the tooth other than the working surface shall be of steel conforming to a-3-634, F3 l-sm-1186. weight shaU be modified with skids in accordance with the box specification. Boxes shall be strapped in accordance with the appendix t
12、o the box specification, except strapping shall be flat steel, type 1, class By and on modified boxes the strapping shall be placed adjacent to the skids. When strapping is placed adjacent to the skids, the filler edge cleats should be wide enough so as not to allow strapping to pass over any voids.
13、 Packing shall be level A, By or Cy 88 specified. Boxes exceeding 250 pounds gross 5.2.3 Level B. The teeth shall be packed as specified for level A, except the boxes shall be domestic type, and strapping shall not be required to be zinc-coated. 5.2.3 kvel C. The teeth shall be prepared for shipment
14、 in a manner to afford protection against deterioration at the lowest ratings of the carrier in compliance with Uniform Freight Classification rules or National Motor Freight Classification rules. 5.3 MarkW. Marking aha be in aucordance with MIL-ERD-129. Provided by IHSNot for ResaleNo reproduction
15、or networking permitted without license from IHS-,-,-6.1 intended use. The teeth are intended for use With scarifier assemblies in ripping the ground by bulldozing-type vehicles duritig the time the-vehicle is traveling in reverse or backing. The teeth are suitable for use in dl types of terrain enc
16、ountered in road construction and similar earth-moving work. 6.2 Order- data. Procurement documents should specify the following: Title, number, and date of this specification. 13 Size required (see 1.2). c) Level of preservation and level of packing required (see 5.1 and 5.2). Custodians: preparing activity: *-ME Air Force - 84 User activities : Navy - D,MC Arnlv-m Project No. 3830-0078 9 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
