This specification covers bridge bearings that consist of a spherical rotational element, where a stainless steel convex surface slides against a concave carbon steel plate covered with woven or sheet polytetrafluoroethylene (PTFE). The function of the bearing is to transfer loads and to accommodate any relative movement, including rotation between a bridge superstructure and its supporting structure, or both. The requirements of spherical bearings with a standard horizontal load (a maximum of 10 % of vertical) are discussed. The bearings are furnished in three types: fixed spherical bearing which is for rotation only, unidirectional sliding spherical bearing which is for rotation plus movement in one direction, and multi-directional sliding spherical bearing which is for rotation plus movement in all directions. The materials to be used in producing the bearings include: steel, stainless steel (flat sliding surface and convex surface), woven fabric polytetrafluoroethylene, and sheet polytetrafluoroethylene. The following different test methods shall be performed: proof load and rotation tests for fixed and expansion bearings, coefficient of friction test for expansion bearings only, PTFE (woven or sheet) bond test for expansion bearings only, and physical property test of both PTFEs for fixed and expansion bearings.1.1 This specification covers bridge bearings that consist of a spherical rotational element, where a stainless steel convex surface slides against a concave carbon steel plate covered with woven or sheet polytetrafluoroethylene (PTFE). The function of the bearing is to transfer loads and to accommodate any relative movement, including rotation between a bridge superstructure and its supporting structure, or both.1.2 This specification covers the requirements of spherical bearings with a standard horizontal load (a maximum of 10 % of vertical).1.3 The requirements stated in this specification are the minima necessary for the manufacture of quality bearing devices. It may be necessary to increase these minimum values due to other design conditions.1.4 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.5 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.1.6 The following safety hazards caveat pertains only to the test method portion, Section 7, of this specification: 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.1.7 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 This test procedure provides a method of evaluating the frictional torque and friction factor of hip replacement bearings.5.2 The procedure may be used as a standardized method of measuring friction to investigate the effects of specific test parameters such as hip materials, sizes, designs, radial or diametral clearance, different lubricants, different deformation levels of the acetabular cup, clamping (non-uniform sphericity), damaged/scratched bearings, artificial ageing, misalignments during installation, etc.5.3 Friction torque, and in particular the maximum value, is useful to assess the applicable torques that may compromise fixation, or even risk disassociation of modular components in the acetabular cup or liner/shell assemblies through a lever-out or torsion-out mechanism.5.4 Friction factor is a useful parameter for comparison of materials and designs, and provides insights into the lubrication regime operating in the implant system. Friction factor measurement may also be able to detect acetabular liner deformation (clamping referred to earlier).5.5 The loading and motion of a hip replacement in vivo differ from the loading and the motion defined in this standard. The amount of frictional forces in vivo will, in general, differ from the frictional forces evaluated by this standard test method. The results obtained from this test method cannot be used to directly predict in vivo performance. However, this standard is designed to allow for in-vitro comparisons for different hip designs, when tested under similar conditions.5.6 Although this test method can be used to investigate the many variables listed in 1.2 and 5.2, it does not either provide a method to determine beforehand the combination of these variables that will produce the worst-case couple(s) among a range of sizes; the worst-case testing condition(s) for “normal” or “adverse” conditions; or provide specific methods to deform the acetabular cup, simulate Mode 3 wear conditions (for example, third-body particles, scratched heads), or artificially aged materials. As these methods are not included in the standard and if they are to become the subject of the investigation then it is up to the user to justify the couple(s) selected and method(s) used in the test and, if necessary, provide a rationale for how the “worst-case” couple(s) and method(s) were selected to represent clinically relevant “normal” and “adverse” conditions as part of the report.1.1 This test procedure provides a method of determining the frictional torque and friction factor of artificial hip joint bearings used in total hip replacement (THR) systems under laboratory conditions using a reciprocal friction simulator. This test method specifies the angular movement between the articulating components, the pattern of applied force, and the way data can be measured and analyzed.1.2 Many variables can be investigated using this test method including, but not limited to, the effect of head size, different inclination/version angles, different deformation levels of the acetabular cup, bearing clearances, lubrication, scratched heads, and artificial ageing.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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： 590元 / 折扣价： 502 元 加购物车

1.1 This specification covers bridge bearings which consist of a confined elastomeric element encased in steel (pot bearings) when the function of the bearing is to transfer loads or accommodate relative movement including rotation between a bridge superstructure and its supporting structure, or both.1.2 This specification covers the requirements of pot bearings with standard horizontal loads (10 % of vertical).1.3 The requirements stated in this specification are the minimums necessary for the manufacture of quality bearing devices. It may be necessary to increase these minimum values due to design conditions.1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are for information only.1.5 The following safety hazards caveat pertains only to the test method portion, Section 7, of this specification: 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 and health practices and determine the applicability of regulatory limitations prior to use

定价： 0元 / 折扣价： 0 元

This specification covers requirements for ferrous and nonferrous inch balls. The balls are intended for use in bearings, bearing applications, check valves, and other components using balls. These balls are classified into fourteen kinds according to their chemical composition: Composition 1 (chrome alloy steel), Composition 2 (corrosion-resistance hardened steel), Composition 3 (carbon steel), Composition 4 (silicon molybdenum steel), Composition 5 (brass), Composition 6 (bronze), Composition 7 (aluminum bronze), Composition 8 (beryllium copper alloy), Composition 9 (nickel-copper alloy or Monel), Composition 10 (nickel-copper-aluminum alloy or K-Monel), Composition 11 (aluminum alloy), Composition 12 (tungsten carbide), Composition 13 (premium quality bearing steel or double vacuum melted M-50), and Composition 14 (corrosion resisting unhardened steel). Ball samples shall be subjected to a series of tests in order to determine the following properties: density, hardness, fracture grain size, porosity, surface roughness, decarburization, case depth, and passivation. Eddy current test, visual test, and dimensional test shall also be performed.1.1 This specification covers requirements for ferrous and nonferrous inch balls. The balls covered in this specification are intended for use in bearings, bearing applications, check valves, and other components using balls.1.2 This is a general specification. The individual item requirements shall be as specified herein in accordance with the MS sheet standards. In the event of any conflict between requirements of this specification and the MS sheet standards, the latter shall govern.1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.4 This specification contains many of the requirements of MIL-B-1083, which was originally developed by the Department of Defense and maintained by the Defense Supply Center Richmond.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 and health practices and determine the applicability of regulatory requirements prior to use.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 This guide is intended as a guideline for justification of oil test selection for monitoring rolling element ball type bearing conditions in industrial applications. Continuous benchmarking against similar applications is required to ensure lessons learned are continuously implemented.5.2 Selection of oil tests for the purpose of detecting rolling element ball type bearing failure modes requires good understanding of equipment design, operating requirements and surrounding conditions. Specifically, detailed knowledge is required on bearing design configuration, dimensional tolerances, load directions, design limitations, lubrication mechanisms, lubricant characteristics, and metallurgy of lubricated surfaces including bearing cages. Equipment criticality and accessibility as well as application of other monitoring techniques (for example, vibration, ultrasound or thermal images) are also critical information in this analysis process. In addition, detailed knowledge on the lubricating oil is paramount.5.3 To properly apply the FMEA methodology users must understand the changes the system may encounter during all operating modes, their impact on design functions and available monitoring techniques capable of detecting these changes. To assist this approach, Section 6 will provide extensive descriptions on the rolling element ball type bearing failure modes, their causes and effects.5.4 It is recognized that in most industrial applications vibration monitoring is the primary condition monitoring technique applied to detect failure modes, causes and effects in rolling element ball type bearings—while oil analysis is primarily used to monitor the lubricating oil properties. In the recent years, however, there is a trend toward using oil analysis in order to provide earlier detection of some failures of rolling element ball type bearings. This is particularly applicable to complex dynamic systems such as compressors, gearboxes and some gas turbines where obtaining vibration spectra and their analysis may be more difficult.1.1 This guide approaches oil analysis from a failure standpoint and includes both the rolling element ball type bearing wear and fluid deterioration in industrial application.1.2 This guide pertains to improving equipment reliability, reducing maintenance costs and enhancing the condition-based maintenance program primarily for industrial machinery by applying analytical methodology to oil analysis program for the purpose of detecting specific failure modes.1.3 This guide reinforces requirements for appropriate assembly, operation within the original design envelope as well as the need for condition-based and time-based maintenance.1.4 This guide covers the principles of Failure Mode and Effect Analysis (FMEA) as described in Guide D7874 and its relationship to rolling element ball type bearing wear in industrial application and its fluid deterioration.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： 590元 / 折扣价： 502 元 加购物车

1.1 This specification covers iron-copper-tin-graphite sintered metal powder oil-impregnated bearings of one composition commonly known as diluted bronze.1.2 The following safety hazards caveat pertains only to the test method described in this specification: 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 and health practices and determine the applicability of regulatory limitations prior to use.

定价： 0元 / 折扣价： 0 元

The volume of an arbitrary P/M shape cannot be accurately measured by standard techniques such as by micrometers or calipers. Since density is mass/volume, a precise method to measure the volume is needed. For nonporous objects, the volume of water displaced by the immersed object is determined by Archimedes principle. For porous P/M parts, a method is required to seal surface connected pores. If the pores are not sealed or the part is not oil impregnated, the part will absorb some of the water and decrease its buoyancy and exhibit an erroneously high density.Density and oil content values are generally contained in the specifications for oil-impregnated bearings and other self-lubricating P/M parts. Desired lubrication requires sufficient interconnected porosity and satisfactory oil impregnation of the porosity.For a particular P/M material, the mechanical properties of P/M structural parts are directly related to their density. Density values are therefore generally contained in the specifications for P/M parts.1.1 This test method covers determination of the density, oil content, and interconnected porosity of sintered bearings and structural parts with or without oil impregnation.1.2 The values stated in SI units are to be regarded as the 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 and health practices and determine the applicability of regulatory limitations prior to use.

定价： 0元 / 折扣价： 0 元

5.1 This test method differentiates among greases having distinctly different low-temperature characteristics. This test is used for specification purposes and correlates with its precursor which has been used to predict the performance of greases in automotive wheel bearings in low-temperature service.5 It is the responsibility of the user to determine the correlation with other types of service.1.1 This test method covers the determination of the extent to which a test grease retards the rotation of a specially-manufactured, spring-loaded, automotive-type wheel bearing assembly when subjected to low temperatures. Torque values, calculated from restraining-force determinations, are a measure of the viscous resistance of the grease. This test method was developed with greases giving torques of less than 35 N·m at −40 °C.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 WARNING—Mercury has been designated by many regulatory agencies as a hazardous substance that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Use Caution when handling mercury and mercury-containing products. See the applicable product Safety Data Sheet (SDS) for additional information. The potential exists that selling mercury or mercury-containing products, or both, is prohibited by local or national law. Users must determine legality of sales in their location.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： 590元 / 折扣价： 502 元 加购物车

1.1 This specification covers bridge bearings that consist of an unconfined polyether urethane rotational element subjected to compression loads, along with a resisting mechanism to transmit shear and/or tension loads through the bearing. For expansion and/or contraction applications, an additional stainless steel flat surface slides against a carbon steel plate faced with sheet polytetrafluoroethylene (PTFE). The function of the bearing is to transfer loads and to accommodate any relative movement, including rotation between a bridge superstructure and its supporting structure, or both.1.2 The requirements stated in this specification are the minimums necessary for the manufacture of quality bearing devices. It may be necessary to increase these minimum values due to other design or construction conditions.1.3 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.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： 590元 / 折扣价： 502 元 加购物车

This specification covers the establishment of requirements for lined journal bearings for use on locomotive tenders, passenger cars, and freight equipment cars. Before lining, the brass backs shall be bored and thoroughly tinned in accordance with the best standard practice. After lining, the ends of the bearings shall be made smooth by scraping, filing, or machining. The backing metal shall conform to the requirements specified for named elements for copper alloy UNS No. C94100. The lining metal shall conform to the chemical composition requirements specified for named elements. The finished bearing representing a lot for acceptance shall be broken, either longitudinally or transversely, or both, in order to ascertain the uniformity of the grain of the metal. The chemical analysis of the lining shall be made accordingly.1.1 This specification covers the establishment of requirements for lined journal bearings for use on locomotive tenders, passenger cars, and freight equipment cars. The alloy specified is UNS No. C94100.21.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.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： 515元 / 折扣价： 438 元 加购物车

This specification covers annular ball bearings intended primarily for use in instrument and precision rotating components. Annular ball bearings for instrument and precision rotating components shall be of the following types, as specified: type I - deep groove, unflanged; type II - deep groove, flanged; type III - deep groove, unflanged, inner ring extended; type IV - deep groove, flanged, inner ring extended; type V - angular contact, unflanged, nonseparable, and counterbored outer ring; type VI - angular contact, flanged, nonseparable, and counterbored outer ring on flange side; type VII - angular contact, unflanged, separable, and stepped inner ring; type VIII - angular contact, flanged, separable, and stepped inner ring; type IX - angular contact, unflanged, nonseparable, and stepped inner ring. Materials inspection, passivation test, visual inspection, dimensional inspections, radial internal clearance, torque test, ball quality inspection, hardness test, surface roughness test, dimensional stability test, lubricant inspection, and calibration classification inspection shall be performed to meet the requirements prescribed.1.1 This specification covers annular ball bearings intended primarily for use in instrument and precision rotating components. Instrument and precision ball bearings should meet tolerances specified in ABMA Standard 12.2, Instrument Ball Bearings Inch Design for Classes ABEC 5P and 7P.1.2 Intended Use—Ball bearings defined by this specification are intended for use in critical components of instrument systems. Such components range from air circulating blowers and drive motors through precision gear trains, gyro gimbals, and pickoffs to rate integrating spin-motors.1.3 The specification contains many of the requirements of MIL-B-81793, which was originally developed by the Department of Defense and maintained by the Naval Air Systems Command (Navy-AS) in Lakehurst, NJ. The following government activity codes may be found in the Department of Defense, Standardization Directory SD-1.2Preparing activity Custodians Review activitiesNavy - AS Army - AT Army-AV  Navy - AS Navy - MC, SH  Air Force - 99 Air Force–84  DLA - GS  1.4 Classification—Annular ball bearings for instrument and precision rotating components shall be of the following types, as specified:1.4.1 Type I—Annular ball bearing, for instruments and precision rotating components, deep groove, unflanged; (See Annex A1 – Annex A4)1.4.2 Type II—Annular ball bearing, for instruments and precision rotating components, deep groove, flanged; (See Annex A5 – Annex A8)1.4.3 Type III—Annular ball bearing, for instruments and precision rotating components, deep groove, unflanged, inner ring extended; (See Annex A9 – Annex A12)1.4.4 Type IV—Annular ball bearing, for instruments and precision rotating components, deep groove, flanged, inner ring extended; (See Annex A13 – Annex A16)1.4.5 Type V—Annular ball bearing, for instruments and precision rotating components, angular contact, unflanged, nonseparable, and counterbored outer ring; (See Annex A17 – Annex A20)1.4.6 Type VI—Annular ball bearing, for instruments and precision rotating components, angular contact, flanged, nonseparable, and counterbored outer ring on flange side; (See Annex A21 – Annex A24)1.4.7 Type VII—Annular ball bearing, for instruments and precision rotating components, angular contact, unflanged, separable, and stepped inner ring; (See Annex A25 – Annex A28)1.4.8 Type VIII—Annular ball bearing, for instruments and precision rotating components, angular contact, flanged, separable, and stepped inner ring; (See Annex A29 – Annex A32)1.4.9 Type IX—Annular ball bearing, for instruments and precision rotating components, angular contact, unflanged, nonseparable, and stepped inner ring. (See Annex A33 – Annex A36)1.5 Inch-Pound Specification—This specification covers only the inch-pound bearings.1.5.1 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.1.6 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.1.7 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： 1189元 / 折扣价： 1011 元 加购物车

定价： 689元 / 折扣价： 586 元 加购物车

4.1 This practice is intended for the application of in-line, full-flow inductive wear debris sensors. According to (1), passing the entire lubrication oil flow for aircraft and aero-derivative gas turbines through a debris-monitoring device is a preferred approach to ensure sufficient detection efficiency.4.2 Periodic sampling and analysis of lubricants have long been used as a means to determine overall machinery health (2). The implementation of smaller oil filter pore sizes for machinery operating at higher rotational speeds and energies has reduced the effectiveness of sampled oil analysis for determining abnormal wear prior to severe damage. In addition, sampled oil analysis for equipment that is remote or otherwise difficult to monitor or access is not practical. For these machinery systems, in-line wear debris sensors can be very useful to provide real-time and near-real-time condition monitoring data.4.3 In-line full-flow inductive debris sensors have demonstrated the capability to detect and quantify both ferromagnetic and non-ferromagnetic metallic wear debris. These sensors record metallic wear debris according to size, count, and type (ferromagnetic or non-ferromagnetic). Sensors are available for a variety of oil pipe sizes. The sensors are designed specifically for the protection of rolling element bearings and gears in critical machine applications. Bearings are key elements in machines since their failure often leads to significant secondary damage that can adversely affect safety, operational availability, or operational/maintenance costs, or a combination thereof.4.4 The main advantage of the sensor is the ability to detect early bearing damage and to quantify the severity of damage and rate of progression of failure towards some predefined bearing surface fatigue damage limiting wear scar. Sensor capabilities are summarized as follows:4.4.1 In-line full flow non-intrusive inductive metal detector with no moving parts.4.4.2 Detects both ferromagnetic and non-ferromagnetic metallic wear debris.4.4.3 Detects 95 % or more of metallic wear debris above some minimum particle size threshold.4.4.4 Counts and sizes wear debris detected.4.5 Fig. 1 presents a widely used diagram (2) to describe the progress of metallic wear debris release from normal to catastrophic failure. It must be pointed out that this figure summarizes metallic wear debris observations from all the different wear modes that can range from polishing, rubbing, abrasion, adhesion, grinding, scoring, pitting, spalling, etc. As mentioned in numerous references (1-11), the predominant failure mode of rolling element bearings is spalling or macro pitting. When a bearing spalls, the contact stresses increase and cause more fatigue cracks to form within the bearing subsurface material. The propagation of existing subsurface cracks and creation of new subsurface cracks causes ongoing deterioration of the material that causes it to become a roughened contact surface as illustrated in Fig. 2. This deterioration process produces large numbers of metallic wear debris with a typical size range from 100 to 1000 microns or greater. Thus, rotating machines, such as gas turbines and transmissions, which contain rolling element bearings and gears made from hard steel tend to produce this kind of large metallic wear debris that eventually leads to failure of the machines.FIG. 1 Wear Debris CharacterizationFIG. 2 Typical Bearing Spall4.6 In-line wear debris monitoring provides a more reliable and timely indication of bearing distress for a number of reasons:4.6.1 Firstly, bearing failures on rotating machines tend to occur as events often without sufficient warning and could be missed by means of only periodic inspections or data sampling observations.4.6.2 Secondly, since it is the larger wear metallic debris that are being detected, there is a lower probability of false indication from the normal rubbing wear that will be associated with smaller particles.4.6.3 Thirdly, build or residual debris from manufacturing or maintenance actions can be differentiated from actual damage debris because the cumulative debris counts recorded due to the former tend to decrease while those due to the latter tend to increase.4.6.4 Fourthly, bearing failure tests have shown that wear debris size distribution is independent of bearing size. (2-5) and (11).1.1 This practice covers the minimum requirements for an in-line, non-intrusive, through-flow oil debris monitoring system that monitors ferromagnetic and non-ferromagnetic metallic wear debris from both industrial aero-derivative and aircraft gas turbine engine bearings. Gas turbine engines are rotating machines fitted with high-speed ball and roller bearings that can be the cause of failure modes with high secondary damage potential. (1)21.2 Metallic wear debris considered in this practice range in size from 120 μm (micron) and greater. Metallic wear debris over 1000 μm are sized as over 1000 μm.1.3 This practice is suitable for use with the following lubricants: polyol esters, phosphate esters, petroleum industrial gear oils and petroleum crankcase oils.1.4 This practice is for metallic wear debris detection, not cleanliness.1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are provided for information only.1.6 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.1.7 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

5.1 The radial crushing strength test is a destructive procedure used to determine a material strength characteristic of PM bearings and hollow cylindrical test specimens. These data can be used to grade, classify, and evaluate the materials.5.2 The PM bearing Specifications B438 and B439 require the use of this test method as an acceptance test for the strength of oil-impregnated sintered bearings.5.3 This test method may be used by powder producers and parts manufacturers as a lot acceptance test for metal powders and lubricated powder mixtures intended for the production of porous parts.5.4 Companies in the PM industry use this test as a manufacturing control test because it is appropriate for production practices.5.5 Radial crushing strength is a property of the PM material but is not a design value. However, experience has shown that the radial crushing strength of a material is approximately twice the ultimate tensile strength.1.1 This test method covers the equipment and laboratory procedure for the determination of the radial crushing strength of materials using either a plain powder metallurgy (PM) bearing or a thin-walled hollow cylindrical test specimen. This is a destructive test that produces quantitative results.1.2 Limitations: 1.2.1 The principle of this procedure is based on the material being tested having minimal ductility. The permanent deflection of the cylinder during the test should not exceed 10 % of the outside diameter.1.2.2 The radial crushing strength test results should be used only as a guide if the test specimen has a wall thickness that is greater than one-third of the outside diameter. These test results should then only be used for comparison with data from the test specimens of like materials and similar dimensions.1.3 Units—With the exception of the values for density and the mass used to determine density, for which the use of the gram per cubic centimetre (g/cm3) and gram (g) units are the industry standard, the values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.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

In service, there is a space between a shaft and a self-lubricating PM bearing that contains an oil film when the bearing is operating properly. In the event the oil film is disrupted or fails to form the bearing will exhibit increased wear and possibly fail. Therefore the ability for oil to flow through the porosity of a PM bearing is critical to the performance of the bearing.The porosity of the bearing must be open to the surface and interconnected within the bearing. This allows the oil in a self-lubricating PM bearing to flow during operation to the space between the bearing and the shaft to form an oil film and protect the shaft from wear.The ability of a gas to flow through the bearing reflects the openness and interconnected properties of the porosity in the bearing.Data from this test can be used as an internal quality tool and can be reported to buyers of bearings.A number of other factors also affect the performance of the bearing and the movement of oil; factors such as the oil viscosity, operating temperature, load, shaft speed, surface area, surface finishes and others. This test provides information on only one property and cannot be the sole consideration in the design and testing of a bearing application.1.1 This test method covers the determination of the permeability of a PM bearing when subjected to pressurized nitrogen under controlled conditions.1.2 The values stated in SI units are to be regarded as the standard with the exception of flow rate for which the cm3/min unit is the industry standard.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 and health practices and determine the applicability of regulatory limitations prior to use.

定价： 0元 / 折扣价： 0 元