1 Scope This International Standard specifies minimum performance and test criteria for brake systems to enable uniform assessment of the braking capability of earth-moving machinery which operates on work sites or travels on public roads. Service seco

定价： 364元 / 折扣价： 310 元

5.1 Braking traction is an important factor in vehicle control especially on wet pavements. These test methods permit an evaluation of tires for their relative or comparative performance on an ABS-equipped vehicle. See Annex A1 for background information for interpretation of results and meaningful evaluation of tire design features for their influence on wet traction performance.5.2 Although stopping distance is important for vehicle control, the ability to steer the vehicle on a selected trajectory is equally or, in some instances, more important. The wet traction capability of tires influences both of these measured parameters since the tires are the link between the ABS and the pavement and provide the traction or tire adhesion level that permits the ABS to function as intended.5.3 The absolute values of the parameters obtained with these test methods are highly dependent upon the characteristics of the vehicle, the design features of the ABS, the selected test pavement(s), and the environmental and test conditions (for example, ambient temperature, water depths, test speeds) at the test course. A change in any of these factors may change the absolute parameter values and may also change the relative rating of tires so tested.5.4 These test methods are suitable for research and development purposes where tire sets are compared during a brief testing time period. They may not be suitable for regulatory or specification acceptance purposes because the values obtained may not necessarily agree or correlate, either in rank order or absolute value, with those obtained under other conditions (for example, different locations or different seasonal time periods on the same test course).1.1 These test methods cover the measurement of two types of ABS vehicle behavior that reflect differences in tire wet traction performance when the vehicle is fitted with a series of different tire sets to be evaluated.1.1.1 The stopping distance from some selected speed at which the brakes are applied.1.1.2 The lack of control of the vehicle during the braking maneuver. Uncontrollability occurs when the vehicle does not follow the intended trajectory during the period of brake application despite a conscious effort on the part of a skilled driver to maintain trajectory control. Uncontrollability is measured by a series of parameters related to this deviation from the intended trajectory and the motions that the vehicle makes during the stopping maneuver.1.1.3 Although anti-lock braking systems maintain wheel rotation and allow for a high degree of trajectory control, different sets of tires with variations in construction, tread pattern, and tread compound may influence the degree of trajectory control in addition to stopping distance. Thus vehicle uncontrollability is an important evaluation parameter for tire wet traction performance.1.2 These test methods specify that the wet braking traction tests be conducted on two specially prepared test courses: (1) a straight-line (rectilinear) “split-µ” (µ = friction coefficient) test course, with two test lanes deployed along the test course (as traveled by the test vehicle); the two lanes have substantially different friction levels such that the left pair of wheels travels on one surface while the right pair of wheels travels on the other surface; and (2) a curved trajectory constant path radius course with uniform pavement for both wheel lanes.1.3 As with all traction testing where vehicle uncontrollability is a likely outcome, sufficient precautions shall be taken to protect the driver, the vehicle, and the test site facilities from damage due to vehicle traction breakaway during testing. Standard precautions are roll-bars, secure mounting of all internal instrumentation, driver helmet, and secure seat belt harness, etc.1.4 The values stated in SI units are to be regarded as the standard. The values given in parenthesis are for information only.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 646元 / 折扣价： 550 元 加购物车

1. Scope 1.1 This Standard describes minimum performance criteria for the service braking system, secondary braking system, and parking system for rubber-tired, self-propelled underground mining machines with maximum rated speeds of 32 kph or less and

定价： 319元 / 折扣价： 272 元

3.1 The terminology listed below allows for standardized and specific language to be given to concepts surrounding the identification of, recording, and communication of vehicle wheel braking. The terms are designed to specifically allow manufacturers, operators, regulators, research agencies, and investigative agencies the ability to communicate essential concepts in a manner that can be directly applied to operational requirements.1.1 The terms and definitions listed provide a common set of definitions and concepts that have been agreed upon by the Society of Aircraft Performance and Operations Engineers. While historical reports and studies may use different terms, all concepts should be relatable to the definitions listed.1.2 Several discussion sections are included to provide context. The definitions and discussions serve to formally capture industry best practices and common methods that relate to aircraft certification, aircraft operation, and airport operations under standard FAA and ICAO guidance.1.3 Units—The values stated in SI units are to be regarded as standard. There are no SI units used in these definitions. New values relating to braking coefficients are described below.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车

The knowledge of vehicle stopping distance or deceleration serves as an additional tool in characterizing the pavement surface skid resistance. When used in conjunctionwith other physical and chemical tests, the skid resistance values derived from these test methods may determine the suitability and adequacy of paving materials or finishing techniques. Improvements in pavement maintenance practices and schedules may result from use of these test methods.The stopping distance or deceleration values measured by these two test methods with the equipment and procedures stated herein do not necessarily agree or correlate directly with other methods of skid-resistance measurements. These test methods are suitable where direct comparison between pavement surfaces are to be made within the same test program.1.1 These test methods cover the measurement of skid resistance on paved surfaces with a passenger vehicle equipped with specified full-scale vehicle tires and using the diagonal braking mode. These test methods include the following:1.1.1 Full-Stop Method This represents the nonsteady-state skid resistance on two diagonally locked wheels, as the vehicle decelerates over a wetted pavement surface under specified limits of static wheel load and from a desired speed. The vehicle shall remain essentially parallel to its original direction of motion.1.1.2 Pulse-Braking MethodThe deceleration resulting from momentary diagonal wheel lockup (pulse braking) is measured. The vehicle decelerates over a wetted pavement surface under specified limits of static wheel load and at a desired speed. The vehicle shall remain essentially parallel to its original direction of motion.1.2 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents: therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.

定价： 0元 / 折扣价： 0 元

5.1 The terminology within this guide references ASTM Terminology E3188. These terms should be thoroughly familiarized before a review of this guide is accomplished.5.2 U.S. and international guidance advocate that transport aircraft perform a time-of-arrival landing assessment for all runway conditions to include dry, wet, and contaminated surfaces. The function of this assessment is to provide an operator with a standardized means for anticipating the level of braking action upon landing. An aircraft braking action report is then created based on the actual level of braking achieved. This information can then be communicated for analysis.5.3 The use of aircraft data to generate an aircraft braking action report is intended to mitigate human errors due to issues of training, experience, or cognitive bias that may occur with pilot braking action reports. For aircraft that use FAA AC 25-32 or equivalent (ICAO Doc 10064 and AMC 25.1592, for example) to assess landing performance, aircraft braking action reports can be considered applicable to a wide range of aircraft types and manufacturers.5.4 The ABAR produced by such a system may not result in an observation representative of the entire prepared surface intended to be used for landing, deceleration, or both.5.5 It is the responsibility of the aircraft and airport operator to create policies and procedures regarding the use of an ABAR. It is important to fully understand the capabilities and any limitations that may exist with such a system. It is the responsibility of the aircraft operator to ensure that proper training and system knowledge are in place prior to the use of these systems.5.6 FAA and ICAO guidance use the term Aircraft Wheel Brake Coefficient or MU Brakes (see Terminology E3188) to define the reference distances to be used by the flight crew in accomplishing a time-of-arrival landing assessment. MU Brakes is also commonly used in research programs and accident investigations. While the use of this term is a standard industry practice, other means of quantifying aircraft wheel braking performance may be employed.5.7 Aircraft of different manufacturers and type designs may use a variety of data sources. Therefore, this process of quantification cannot be universally detailed for all aircraft. This standard describes requirements for specific data, as well as categories of data that may be measured or inferred so that an appropriate calculation method may be employed.5.8 This standard may be used to support the design and operation of a variety of intended functions. The specific description of each function will determine the compliance methods that should be followed.NOTE 1: Intended functions may include the simple transmission of data, flight crew alerting, the discrimination of a simple boundary between two braking levels, or a multitude of braking levels.5.9 There is a wide range of methods that may be used to show compliance. The party responsible for assessing an applicant’s compliance should use this standard as a guide; however, the specific methods deemed acceptable may be determined based on the specifics of the design.5.10 This standard is intended to be applicable to any aircraft with an anti-skid system and available flight data. A nominal rate of data acquisition of 4 Hz represents requirements for flight data recorders. Data sample requirements are intended to allow older model aircraft and anti-skid systems enough information to demonstrate stable performance characteristics.5.11 ABAR systems are intended to reflect a portion of the landing area that can reasonably be considered relevant for operational decision-making. It is incumbent on the end user to incorporate policies and procedures to appropriately utilize this information in a safety management process.5.12 Mapping Accuracy—Compliance with this standard is intended to provide an ABAR produced by a system in which there is reasonable confidence that the reported braking action will be within ± one level of wheel braking, when using the six (6) categories of braking action reports as documented in FAA AC 25-32 or 10.2.2. For systems using fewer than six (6) levels of braking action, the standard for data precision will remain the same and the accuracy therefore increased.NOTE 2: Dry runway conditions are not described using braking action.5.13 Deviations from this standard may be considered acceptable if they are appropriately documented and justified.5.14 The list of parameters included in Annex A1 is categorized to maximize the ability of the designer to adhere to the philosophies documented herein. The list in this standard should be considered a minimum list of parameters normally available from an aircraft’s data system. These parameters are then used in modeling aerodynamics, propulsion, and other forces. A method of direct measurement or alternate means of determining wheel braking characteristics may result in a deviation from this list.1.1 This guide applies to any automated system that uses data from an aircraft to create an Aircraft Braking Action Report (ABAR) (see Terminology E3188). The system may be installed on an aircraft or operated remotely. This standard is intended to ensure that all ABARs created by automated systems meet a minimum level of quality and represent a standardized set of assumptions. This standard does not provide any guidance or means for the dissemination of an ABAR or related information.1.1.1 Aircraft systems producing ABARs or ABAR-related flight crew alerts are covered by the appropriate regulatory guidance for aircraft certification.1.2 This standard utilizes the terms and methods relating to aircraft anti-skid systems as documented in FAA AC 25-32.1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 Risk Management—Aircraft braking action reports contain information that may be used to reference the operating limits of an aircraft. Section 6 details the safety analysis and specific guidelines for airborne and remotely operated systems.1.5 Operational Use—This standard does not address operational considerations nor recommend policies regarding the use of an aircraft braking action report.1.6 Mandating and Recommended Phrases—To enhance comprehension and clarity, required and recommended tasks are listed with the following nomenclature:1.6.1 The term “shall” is used to indicate a provision is mandatory. Such requirements are sequentially listed as “REQXX.”1.6.2 The term “should” is used to indicate that a provision is recommended as a good practice. Such recommendations are sequentially listed as “RECXX.”1.7 This standard provides guidance for performing one or more specific functions. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this standard may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project’s many unique aspects. The word “Standard” in the title means only that the document has been approved through the ASTM consensus process.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 646元 / 折扣价： 550 元 加购物车

1.1 This test method covers the measurement of braking traction of tires designed for and mounted on passenger cars or light trucks traveling straight ahead on a wet paved surface. 1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only. 1.3 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

定价： 0元 / 折扣价： 0 元

5.1 The measured values are traction properties of tires obtained with the towed trailer described here on a given road surface, under given environmental conditions (ambient and road surface temperature, humidity, wind speed and direction, purity and film depth of water used to wet the road surface). They are carried out in accordance with the stated test procedures and reflect the performance of the total tire-vehicle environmental system. A change in any of these factors may change the measurements on a subsequent run of the test.5.2 These test methods are suitable for research and development purposes, where tires are compared during a single series of tests. They may not be suitable for regulatory statutes or specification acceptance, because the values obtained may not necessarily agree or correlate either in rank order or absolute traction performance level with those obtained on other road surfaces (or the same surface after additional wear), under other environmental conditions, or other towed trailers, or other test devices, or with results obtained with other test procedures.1.1 This test method covers the measurement of braking traction of tires designed for passenger cars or light trucks. Such braking traction measurements are applicable to conditions wherein the vehicle is traveling straight ahead on a wet, paved surface.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 Calibration is essential in the use of various test platforms and devices to insure that the test results generated by these test devices are accurate, repeatable and meaningful. This standard gives the necessary instructions for the calibration of all of the test devices cited in the .1.1 This practice gives procedures for the calibration of:reference load cellscalibration platform systems by using a reference load cellstatic calibration of braking/tractive force on locked wheels of tire test trailers, instrumented vehicles, and laboratory tire testing machines by using the calibration platform system as a calibration fixture.1.2 The values stated in SI units are to be regarded as standard. The values in parentheses are for information only.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 Pavement surfaces have different traction characteristics, depending on many factors. Surface texture, binder content, usage, environmental exposure, and surface conditions (that is, wet, dry) are some of the factors.5.2 The measured values represent peak braking coefficients for tires of the general type in operation on passenger vehicles, obtained with a towed test trailer on a prescribed road surface, under user-defined surface conditions. Such surface conditions may include the water depth used to wet the road surface and the type of water application method. Variations in these conditions may influence the test results.1.1 This test method covers the measurement of peak braking coefficient (PBC) of paved surfaces using a standard reference test tire (SRTT) as described in Specification E1136 or F2493 that represents current technology passenger car radial tires. General test procedures and limitations are presented for determining peak braking coefficient independent of surface conditions. Actual surface test conditions are determined and controlled by the user at the time of test. Test and surface condition documentation procedures and details are specified. This measurement quantifies the peak braking coefficient at the time of test, and does not necessarily represent a maximum or fixed value.1.2 There are many specifications published that refer to the ASTM E1337 PBC Standard assuming the E1136 SRTT in determining peak brake coefficient. Correlation equations for converting data collected using an F2493 SRTT to the older E1136 specification, and converting an older E1136 specification for use with F2493 data, are included in 12.4.1.3 This test method utilizes a measurement representing the peak braking force on a braked test tire passing over a road surface. This test is conducted with a tire under a nominal vertical load at a constant speed while its major plane is parallel to its direction of motion and perpendicular to the pavement.1.4 The measured peak braking coefficient obtained with the equ