1、Comments, suggestions, or questions on this document should be addressed to: U.S. ARMY TOPOGRAPHIC ENGINEERING CENTER, ATTN: CEERD-TS-T, 7701 TELEGRAPH ROAD, ALEXANDRIA, VA 22315-3864 or emailed to pd-tetec.army.mil . Since contact information can change, you may want to verify the currency of this
2、address information using the ASSIST Online database at www.dodssp.daps.mil . AMSC N/A FSC 6675 Distribution Statement A. Approved for public release; distribution is unlimited. A-A-52036B 28 June 2004 SUPERSEDING A-A-52036A 20 September 1999 COMMERCIAL ITEM DESCRIPTION LEVEL, SURVEYING, SELF-LEVELI
3、NG, AND TILTING The General Services Administration has authorized the use of this Commercial Item Description (CID) for all federal agencies. The original issue of this CID replaced MIL-L-52918. 1. SCOPE. 1.1 Abstract. This commercial item description covers levels (instruments) used for taking dif
4、ferential elevation measurements, in surveying and other engineering applications. The complete instrument shall consist of an internal focusing telescope capable of 360 degree rotation, image lens system, cross hairs (horizontal and vertical), leveling system, tripod, and accessories. 2. CLASSIFICA
5、TION. The levels shall be classified as follows: Type I Tilting level Style A With plane-parallel optical micrometer attachment Style B Without plane-parallel optical micrometer attachment Type II Self-leveling level Style A With horizontal circle graduations Style B Without horizontal circle gradua
6、tions Class 1 1st order accuracy Class 2 2nd order accuracy METRIC Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-52036B 23. SALIENT CHARACTERISTICS. 3.1 Accuracy. Accuracy shall be certifiable, for the life of the level, to permit not greater t
7、han 1.54 seconds of error (1storder) for class 1 instruments; and not greater than 3.07 seconds of error (2ndorder) for class 2 instruments. 3.2 Level types. 3.2.1 Tilting level. A tilting instrument (type I) shall require manual leveling prior to use and periodic checking for maintenance of a level
8、 horizontal line of sight during use. The instrument shall be provided with a circular spirit level, or similar device, for initial coarse leveling and a graduated leveling readout device and leveling screws for precise leveling. The type I, style A level shall be equipped with a parallel-plane opti
9、cal micrometer that allows the operator to measure horizontal distances, within instrument limits. The type I, style B level shall not be equipped with an optical micrometer. 3.2.2 Self-leveling. A self-leveling instrument (type II) shall automatically maintain the telescope in a level position, unt
10、il no longer needed, once the instrument has been manually brought to a defined approximation of level. Type II instruments shall have provisions for measuring horizontal distances. The type II, style A instrument shall have provisions for horizontal full circle angle measurement; the style B instru
11、ment shall not. Type II levels shall be equipped with an automatic compensator, with a working range of not less than 15 seconds of arc, that shall maintain a true horizontal level line of sight at all telescope positions. After telescope rotation, the instrument shall return to true level in not gr
12、eater than 5 seconds. 3.3 Optical system. The optical system of either type instrument shall be aberration free, provide a clear, bright, high contrast, and sharp image throughout the focusing range and field of view. The image may be erect or inverted. Optical properties shall be as follows: a. Mag
13、nification: Not less than 30 diameters at an accuracy of 5 percent b. Objective lens effective aperture: Not less than 39 millimeters (mm) c. Minimum focus distance: Not greater than 3.7 meters d. Minimum field of view: Not less than 60 minutes of arc e. Resolution: Not less than 4 seconds of arc f.
14、 Eye relief distance: Not less than 7 mm 3.3.1 Reticle. The reticle shall be a pattern of permanent opaque lines, on a distortion free, optically transparent medium. It shall be adjustable for precise positioning of the cross hairs, in the horizontal and vertical planes, about the central line of si
15、ght axis of the telescope. The reticle shall be positioned in the eyepiece focus and so as to eliminate distortion during collimation. Horizontal and vertical stadia lines shall be a minimum of 5 minutes of arc in length, parallel to the corresponding cross lines, and spaced at standard stadia line
16、intervals of 1 to 100. The width of all reticle lines shall be 3 seconds of arc, + 0.0 seconds, -0.5 seconds. 3.3.2 Stadia constant. When horizontal distance is measured using the stadia method the difference shall not be greater than 0.3 percent when compared to the verified distance. 3.3.3 Optical
17、 micrometer. When provided, the parallel plate optical micrometer shall measure the interval between the horizontal reticle line and the nearest rod graduation directly to 1 mm. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-52036B 33.4 Level in
18、dicators. 3.4.1 Coarse level indicator. The coarse leveling indicators shall be clearly visible when the instrument is set up, horizontal, and parallel to the line of sight. The level indicator sensitivity shall be by instrument type as follows: a. Type I 10 2 minutes of arc per 2 mm division. b. Ty
19、pe II 7 to 15 minutes of arc per 2 mm division. 3.4.2 Telescope (precise) level indicator. The type I telescope level indicator shall have a sensitivity of 8 to 10 seconds of arc, per 2 mm movement. Level indicator readings shall be clearly discernible in temperatures of -25 to +120F. 3.5 Mounting.
20、The instrument shall be mounted on a tribrach with a baseplate and leveling screws. Leveling screws shall operate without binding, backlash, or end play in temperatures of -25 to +120F. For interface with existing instruments, the tribrach shall have at its center a means of accepting an instrument
21、mounting screw with .625 (5/8)11 UNC2B thread in accordance with ASME B1.1. When leveled, the instrument shall smoothly and easily rotate through a full horizontal circle without binding or end play. 3.6 Horizontal circle. When provided, the horizontal circle shall have index marks graduated in one-
22、degree intervals, labeled at 10-degree intervals, in a clockwise direction. Angle readings to the nearest 10 minutes shall be visible through a supplied magnifying viewer sufficient to estimate the reading to the nearest minute. The circle shall have a fine adjustment capability for precise position
23、ing of the vertical cross hair in the horizontal circle plane. 3.7 Tripod. The level shall be provided with a wide frame tripod having collapsible legs. A means to secure the legs when collapsed in transport configuration shall be provided. The overall length of the tripod, with legs secured but ful
24、ly extended, shall not be less than 168 cm (66 inches). A head or adapter ring to interface with the tribrach mounting threads shall be supplied. A thread protective cap to be used when the instrument is not mounted on the tripod shall be supplied. A means of secure storage for the cap, when not in
25、use, shall be provided on the tripod. The tripod material shall be of sufficient strength to rigidly support the instrument and rugged enough to withstand large changes in temperature or humidity. Leg ends shall be configured for penetration of hard natural surfaces with the application of force. 3.
26、8 Accessories. The instrument shall be provided with the following accessories. a. Lens cleaning brush b. Screwdriver for instrument adjustment as required c. Adjusting pin for reticle adjustment as required d. Objective lens dust cap e. Eyepiece lens cover f. Objective eyepiece sunshade g. Waterpro
27、of cover for the instrument (level) 3.9 Carrying case. A carrying case for the instrument and accessories shall be provided. The case material shall be sufficiently rugged to withstand normal handling and usage. The case liner shall form fit the instrument and shall be securely attached to the case.
28、 The level shall be secured in the case. The case shall be provided with locking latches. Each case shall contain Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-52036B 4desiccant adequate for the volume of the case. Accessory items shall be comp
29、artmented in the case to prevent damage to themselves and the instrument during handling and transport. A means shall be provided for carrying the case and contents with the instrument in an upright position. 4. REGULATORY REQUIREMENTS. 4.1 Recycled, recovered, or environmentally preferable material
30、s. The offeror/contractor is encouraged to use recovered materials to the maximum extent practicable, in accordance with paragraph 23.403 of the Federal Acquisition Regulation (FAR). 5. QUALITY ASSURANCE PROVISIONS. 5.1 Market acceptability. The levels offered shall be the latest version of the stan
31、dard product of the supplier that has been used in the field for at least one year by commercial organizations. 5.2 Product conformance. The levels offered shall meet the salient characteristics of this CID, conform to the manufactures drawings, specifications, standards, and quality assurance pract
32、ices, and be the same product offered for sale in the commercial market. The government reserves the right to require proof of such conformance. 6. PACKAGING. 6.1 Packaging. Preservation, packing, and marking shall be as specified in the contract or order (see 7.1) 7. NOTES 7.1 Ordering data. Acquis
33、ition documents should include: a. Title, number, and date of this document. b. Type, style, and class of level required (see 2.1). c. Level of preservation and packing required (see 6.1). 7.2 Intended use. The levels shall be used to determine differences in elevation between various pre-selected p
34、oints. For type I, style A, and type II instruments the horizontal distance of the points from the instrument location may be determined. For type II style A instruments horizontal angular measurements between designated points may be determined. Provided by IHSNot for ResaleNo reproduction or netwo
35、rking permitted without license from IHS-,-,-A-A-52036B 57.3 Part identification number (PIN). The following part identification numbering procedure is for government purposes and does not constitute a requirement for the contractor. This example describes a part numbering system for CID A-A-52036B
36、AA52036XYZ Class: Class 1 = First order; error not greater than 1.54 seconds Class 2 = Second order; error not greater than 3.07 seconds Type I = Tilting level Style A = With plane parallel optical micrometer Style B = Without plane parallel optical micrometer Type II = Self leveling level Style A =
37、 With horizontal circle Style B = Without horizontal circle Document identifier Example: AA52036IIB1A self-leveling instrument, without a horizontal circle, capable of first order accuracy. 7.4 Sources of documents. 7.4.1 Copies of the Federal Acquisition Regulation (FAR) may be obtained from: Super
38、intendent of Documents, U.S. Government Printing Office, Washington, DC 20402. 7.4.2 Copies of ASME B1.1 may be obtained from: American Society of Mechanical Engineers, United Engineering Center, 345 E. 47th St., New York, NY 10017. 7.5 National Stock Numbers (NSNs). NSN 6675-01-076-5465 has been us
39、ed to procure Type 2A2 and 6675-01-054-5012 has been used to procure Type 2B2. 7.6 Subject term (key word) listing. Alidade Collimation Measurement Optics Transit Tribrach Tripod Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-52036B 6The prepari
40、ng activity for this document is: The U.S. Army Topographic Engineering Center, 7701 Telegraph Road, Alexandria, VA 22315-3864. Custodian: Preparing activity: Army - CE3 Army - CE3 Air force - 99 Navy MC (Project 6675-0165) DLA - GS Review activities: Army-CR Civil Review Agency: GSA FSS Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
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