1、Beneficial comments, recommendations, additions, deletions, clarifications, etc. and any data that may improve this document should be sent to: WR-ALC/GRVEC, Robins AFB GA 31098-1813. Since contact information can change, you may want to verify the currency of this address information using the ASSI
2、ST Online database at https:/assist.daps.dla.mil/online . FSC 6635 INCH-POUNDA-A-59876 30 Nov 2010 COMMERCIAL ITEM DESCRIPTION Calibrator, Torque Wrench 5 in-lbs 2000 ft-lbs The General Services Administration has authorized the use of this commercial item description for all federal agencies. 1. SC
3、OPE. This document describes performance requirements for a Torque Wrench Calibrator, and associated dead-weight calibration equipment. The Torque Wrench Calibrator consists of two separate “stations”. The two stations of the Torque Wrench Calibrator must be capable of being operated at the same tim
4、e. These systems are intended for use by civilian and military personnel to perform calibration of torque setting and indicating instruments, force gages, dynamometers, and cable testers. 2. SALIENT CHARACTERISTICS 2.1 Torque Wrench Calibrator description. There shall be one low torque (manual) stat
5、ion for calibrating torque wrenches and screwdrivers, having a range of 5 in-lb to 250 ft-lb and one high torque station for mechanically generated torque, tension, and force calibrator having a range of 30 in-lb to 2000 ft-lb. The design of the torque loader shall be inherently safe, upon failure o
6、f the drive bar and adapter plates; for example, fragments and broken parts shall be contained within the framework of the machine. Any reaction posts or similar structures attached to the frame shall be designed to a safety factor of five or better on ultimate material strength. A method shall be p
7、rovided for restraining torque wrench handles. Reaction bars, and tension cables, in the event that the test item or tension cable disengages from the machine or breaks. The safety restraint shall provide complete protection to the operator during calibration of force gauges, and cable testers. 2.2
8、Design and construction. The Torque Wrench Calibrator shall be designed and constructed so that no parts will work loose in service. It shall be built to withstand the strains, jars, vibrations, and other conditions incident to shipping, storage, installation, and service. It shall be weatherproof a
9、nd designed to prevent the intrusion of water and sand into critical operating components. 2.2.1 Markings. All external devices which require an operational or maintenance interface shall be marked in accordance with MIL-STD-130. Provided by IHSNot for ResaleNo reproduction or networking permitted w
10、ithout license from IHS-,-,-A-A-59876 2 2.2.2 Identification and information plates. An identification plate in accordance with MIL-STD-130 shall be securely attached to the Torque Wrench Calibrator in a readily accessible location. The identification plate shall contain the following information: n
11、omenclature, part number, serial number, date of manufacture, manufacturers name, Commercial and Government Entity (CAGE) code, date of warranty expiration, and National Stock Number (NSN). In accordance with MIL-STD-130, the Torque Wrench Calibrator and any components meeting Unique Identification
12、(UID) criteria shall have UID information permanently affixed near the respective identification plate(s). UID information shall be included as both a bar code and human readable markings. 2.2.3 Fastening devices. All screws, bolts, nuts, pins, and other fastening devices shall be properly designed,
13、 manufactured, and installed with adequate means of preventing loss of torque or adjustment. Cotter pins, lock washers, or nylon patches shall not be used for this purpose, except for the attachment of trim items or as provided in commercial components. Tapped aluminum threads shall have a minimum t
14、hread engagement of at least two times the nominal fastener diameter. 2.2.4 Welders and welding. Welding procedures shall be in accordance with a nationally recognized welding code. The surface parts to be welded shall be free from rust, scale, paint, grease, and other foreign matter. Welds shall be
15、 of sufficient size and shape to develop the full strength of the welded parts. Welds shall transmit stress without cracking or permanent distortion when the parts connected by the welds are subjected to test, proof, and service loadings. 2.2.5 Foolproofness. Where improper installation of an item c
16、auses a malfunction, an asymmetric mounting system shall be provided, where practical, to ensure proper mounting of the item. 2.3 Environmental conditions. 2.3.1 Operating temperature range. The Torque Wrench Calibrator shall be capable of operating in ambient temperatures ranging from 67 degrees F
17、to 79 degrees F, with a relative humidity of 20% to 50% (non-condensing). The temperature and relative humidity shall be continuously monitored and recorded by a monitor located in each room where calibration activities are being conducted. 2.3.2 Storage temperature range. The Torque Wrench Calibrat
18、or shall be capable of being stored in ambient temperatures ranging from -40 degrees F to +160 degrees F, with a relative humidity of up to 95% (non-condensing), with no degradation to performance or requirement for maintenance. 2.4 System dimensions. The high torque station Torque Wrench Calibrator
19、 dimensions, excluding the digital indicator, shall not exceed 45 inches in width, 24 inches in depth, and 50 inches in height, when the slides and other accessories are retracted Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-59876 3 2.5 Perfor
20、mance. The Torque Wrench Calibrator shall meet the following capabilities, unless otherwise specified, following a warm-up period of no greater than thirty minutes. The Torque Wrench Calibrator maximum non-repeatability shall be +/- 0.15% indicated value of the average of five replications, or +/- 0
21、.1 in-oz, whichever is greater, throughout the specified range of 0.5 in-oz to 2000 ft-lb. The Torque Wrench Calibrators maximum creep, measured from the initial reading on loading to the reading after five minutes, must not exceed 0.15% of full scale for each transducer. Torque ranges shall be prov
22、ided such that the following outputs are obtained at the test interfaces: low torque (bidirectional) 5 in-lb to 250 ft-lb; high torque (bidirectional) 30 in-lb to 2000 ft-lb and force from 5 lb to 2000 lb. The total uncertainty shall not exceed +/- 0.5% indicated value for either. Total uncertainty
23、refers to the combined effects of linearity, hysteresis, zero drift, creep, temperature coefficient, and any other error contributions, added to the systematic uncertainty contributed by the calibration standard. 2.5.1 Low torque. The low torque section shall be a bench-top instrument for manual tor
24、que testing from 5 in-lb to 250 ft-lb. All transducers shall be mounted in the same plane of a common fixture. The fixture shall be designed to be turned on its side so that any torque wrench may be oriented with its handle parallel or perpendicular to the floor. This fixture shall be sturdy enough
25、to allow a wrench to be torqued to 250 ft-lb without sliding or reacting on any type of bench-top surface. Clamping mechanisms are permitted; bolting or holding devices which require modification to the bench-top surface are not permitted. The low torque section shall accommodate all instruments whi
26、ch are in torque range. The low torque section shall have a dedicated digital indicator. The digital indicators front panel must be easily viewed and accessed by the operator, when the indicator is placed on a bench-top with a height between 34 and 44 inches and a depth not to exceed 36 inches. All
27、transducers in the low torque section shall be capable of being connected to the digital indicator at all times by cables which are detachable at each end with cannon-plug type connectors. A selector switch on the front panel of the digital indicator shall show the range of each transducer. An indic
28、ator shall also be illuminated next to the active transducer. Since this section of the torque calibrator shall not have a torque generation system, a visual and audible overload indicator shall be provided to alert the operator before the torque cell is overloaded to the point of permanent deformat
29、ion. 2.5.2 High torque. The high torque section shall be a versatile, operator-friendly calibrator for calibrating torque wrenches, multipliers and force gages. The high torque section shall be equipped with a protective mechanism which shall automatically actuate when the load limit of the torque c
30、ell is exceeded (whether the torque is loaded automatically or manually). The operator shall not be required to interact with the calibrator to distinguish which load cell is in use or what the maximum load limit is. The calibrator shall also be equipped with “dummy” drive sockets, for the operator
31、to exercise torque wrenches prior to mounting on the calibrator. The “dummy” drive sockets (sizes , 3/8, , and 1 inch female square) shall be positioned in a location convenient to the operator. 2.5.2.1 Torque generator. The high torque portion of the Torque Wrench Calibrator shall contain a manual
32、or automatic mechanical loader. The mechanical loaders sensitivity must be commensurate with the resolution of the indicator. If a manual loader is used then no more than 30 revolutions shall be required to test the full range of any one test item. Multiple loading mechanisms may be used. Maximum in
33、put torque for manual operation is 8 ft-lb. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-59876 4 2.5.2.2 Torque instrument fixturing. The reaction post must ride on a stable horizontal slider with quick-adjust settings. All reaction posts, fix
34、turing, and adapters must accommodate at least the instruments listed in this document within its torque range, such that the maximum possible misalignment, measured from the transducer platform to the free-standing instrument, is 3Oin any plane. 2.5.3 Torque transducers. Multiple torque transducers
35、 may be used to cover the range of the instrument. Torque transducers shall overlap the range of the next lower capacity by at least 10%. Transducers shall be easily interchangeable within the instrument fixturing and shall all connect via the same quick connect (canon-type plug) output cable to the
36、 digital indicator. The indicator shall identify the transducer selected without operator input. 2.5.4. Digital indicator. Each section of the Torque Wrench Calibrator shall contain an electronic digital readout display capable of displaying the measured torque. At a minimum, the characters shall be
37、 at least 0.5 inch in height. A cathode ray tube monitor shall not be used for this display. 2.5.5 Indications. 2.5.5.1 Visual indications. Visual indication shall be provided on the front panel of the digital indicator to indicate, at a minimum, the following conditions: power on/off, applicable en
38、gineering units, transducer in use range, torque over-range (greater than 100% of transducer range), first Peak-of-Torque, peak, track, and clockwise or counterclockwise operation. 2.5.5.2 Audible indications. Audible indication shall be provided to indicate torque over-range greater than 120% of tr
39、ansducer range. First Peak-of-Torque is defined as the first peak torque value just prior to the torque drop-off which occurs as the wrench begins its “camming action.” This value shall be displayed on the digital indicator for 3 seconds, then automatically rezero. 2.5.6 Calibration. The indicator s
40、hall have a zero adjustment available to the operator and separate calibration adjustments (either electronic or mechanical) available to the calibrating technician through the use of a “password” or “calibration void” sticker. The indicator shall permit interchangeability of transducers within the
41、same range, without requiring hardware changes in the digital indicator. The range of the output millivolt or volt (mV or V) of all transducers delivered shall not exceed 50% of adjustment range of the digital indicator. All fixtures required to calibrate the torque cells using the dead-weight metho
42、d shall be provided. All moment arms (bipolar), cables, weight pans, weights, etc., shall be supplied for on-site calibration of the Torque Wrench Calibrator. Each calibration arm shall overlap at least 10% of the useable range of the next lower capacity arm. Total uncertainty of the generated torqu
43、e shall be documented and shall not exceed +/- 0.05% indicated value or +/- 0.1 in-oz, whichever is greater. No single piece of the calibration fixturing shall exceed 5 ft in length, or 50 lb in weight. 2.5.7 Diagnostics. The indicator shall employ the following functional self-tests. These self-tes
44、ts shall, whenever possible, provide an internal verification of the equipments modes of operation. These self-tests shall require no external standards or devices. A means shall be provided to change any calibration factor or other correction data stored in the memory of the equipment, if available
45、. The high-torque indicator shall be capable of displaying torque and Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-59876 5 force units; the item shall be capable of displaying torque in units of ft-lb, in-lb, in-oz, Newton-meters and meter-kil
46、ograms; the item shall be capable of displaying force in Newtons and pounds. The default shall be torque indicated in units of in-lb. The low torque indicator shall not require force or tension. 2.6 Electrical. 2.6.1 Power requirements. The Torque Wrench Calibrator shall have 120/220 VAC +/- 10%, 50
47、/60 Hz nominal power requirements. A detachable power connector(s) shall be provided with the system. These connectors shall be a NEMA 5-15 style standard plug. 2.6.1.1 Power switch. There shall be an input power on-off switch located on the front panel. A visible light shall indicate when the equip
48、ment main power is on. 2.6.1.2 Power connections. A minimum 5 foot power cord shall be provided with the digital indicator. 2.6.1.3 Torque transducer power connections. A minimum 5 foot detachable cable shall be provided with the indicator for each torque transducer in the low torque section. At lea
49、st one 5 foot minimum detachable cable shall be provided with high torque section. Each section shall include one spare cable. 2.6.1.4 Cable polarization. The polarization of all cable connectors shall be accomplished by a mechanical method that prevents inadvertent mating in more than one position. The polarization shall be accomplished prior to the electrical engagement of the contacts. All plug-in cabling shall be capable of being disconnected without major dis
