1.1
本试验方法包括使用倾斜的发射坡道在平坦的水平表面上启动球体或近似球形的滚动,以确定给定球形在给定表面上的滚动摩擦特性。
1.1.1
实验室间试验中使用了平板上的钢球(参见
附录X1
). 在制定本试验方法的过程中,对果岭上的高尔夫球、运动表面上的足球和曲棍球、a车道上的保龄球、硬木上的篮球和复合表面上的大理石进行了试验,但该试验适用于在任何平坦水平表面上滚动的任何球体。
1.1.2
球体在水平表面上的滚动摩擦受球面形状的刚度、曲率半径、表面纹理、表面上的薄膜以及对立面的性质的影响;有许多因素需要考虑。该测试方法考虑了所有这些因素。感兴趣的球形在感兴趣的表面上滚动,使用标准斜坡启动滚动,使用标准技术测量和处理离开斜坡后的滚动距离。
1.1.3
该试验方法在特定表面的特定球形上产生滚动阻力值。
它旨在比较类似的摩擦系统。例如,不能将特定表面上大理石的滚动阻力与草地上足球的滚动阻力进行比较,因为它们的质量和直径与其滚动的对立面表面非常不同。
1.1.4
不同的发射斜坡适用于不同类型的球形。如果使用中讨论的其中一个发射坡道无法容纳感兴趣的球体
附录X1和
附录X2
,可以开发一个不同的发射斜坡,并在该测试方法的未来修订中添加。
1.2
以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。
1.3
本标准并非旨在解决与其使用相关的所有安全问题(如有)。本标准的用户有责任在使用前制定适当的安全、健康和环境实践,并确定监管限制的适用性。
1.4
本国际标准是根据世界贸易组织技术性贸易壁垒(TBT)委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。
====意义和用途======
5.1
类似滑动摩擦的滚动摩擦取决于许多因素。这是一种涉及滚动表面和对立面性质的系统效应。滑动摩擦力(
F
)通常被认为是由表面特征变形引起的力的总和(
F
s
),来自接触点处的吸引力(原子、分子等)(
F
一
)以及摩擦表面上薄膜和颗粒相互作用产生的力(
F
f
):
滚动摩擦力包括这些力的贡献加上接触表面的相对刚度、球形(球形、橙色等)的直径(曲率)的影响。
)以及其他因素。由于滚动摩擦系统涉及的因素太多,因此滚动阻力可以通过在预期对立面上对感兴趣的球体进行实际测试来进行最佳量化,如本测试方法中所述。
5.2
在无数应用中,量化特定表面上特定球形的滚动特性非常重要。为本试验方法进行的实验室间试验是在硬化钢球上进行的,与滚珠轴承中使用的钢球类似。该试验方法可用于评估不同端面对滚珠轴承滚珠滚动特性的影响。
相反,它可以用作球的质量控制测试。球上的表面缺陷/缺陷/薄膜等可能会影响其滚动方式:在公共对立面上移动的距离。
5.3
该试验方法的工业应用可包括评估球形或接近特殊零件的输送表面:止回阀球、橱柜旋钮、圣诞饰品、马桶浮子等。许多医疗器械使用特殊形状,其中考虑了滚动特性。类似地,许多药品(药丸)的形状为球形或近似球形,该试验方法可用于评估输送或其他原因(如尺寸(质量)检查)的滚动特性。
5.4
球形的滚动摩擦可以在无数运动(足球、高尔夫、曲棍球等)和游戏应用(台球、bocce、玩具等)中考虑。该测试方法可用于对不同球的组成、质量、形状、表面纹理、设计、刚度等的滚动阻力进行排序。同样,该测试方法可用于评估球在不同比赛或游戏表面上滚动的难易程度。
5.5
该试验方法非常适用于球形或大部分球形食品。
例如,通常使用苹果、柑橘、坚果等的滚动距离按大小进行分类,以便营销。它们沿着有角度的表面向下滚动,滚动距离成为尺寸(质量/直径)的函数。本试验方法可用于评估各种滚动表面(地毯、金属、木材等)在分类设备中的适用性。它也可用于球形加工食品(口香糖、硬糖、肉丸等)的食品输送
5.6
最后,该测试方法可作为物理和摩擦学专业学生的有价值的教学工具。
该设备简单、成本低、学生安全。它可以用来演示滚动摩擦的概念以及影响滚动摩擦的因素。
1.1
This test method covers the use of an angled launch ramp to initiate rolling of a sphere or nearly spherical shape on a flat horizontal surface to determine the rolling friction characteristics of a given spherical shape on a given surface.
1.1.1
Steel balls on a surface plate were used in interlaboratory tests (see
Appendix X1
). Golf balls on a green, soccer and lacrosse balls on playing surfaces, bowling balls on an a lane, basketballs on hardwood, and marbles on composite surface were tested in the development of this test method, but the test applies to any sphere rolling on any flat horizontal surface.
1.1.2
The rolling friction of spheres on horizontal surfaces is affected by the spherical shape’s stiffness, radius of curvature, surface texture, films on the surface, the nature of the counterface surface; there are many factors to consider. This test method takes all of these factors into consideration. The spherical shape of interest is rolled on the surface of interest using a standard ramp to initiate rolling and standard techniques to measure and treat the rolled distance after leaving the ramp.
1.1.3
This test method produces a rolling resistance number on a specific spherical shape on a specific surface. It is intended for comparing similar tribosystems. For example, the rolling resistances of marbles on a particular surface are not to be compared with the rolling resistance of soccer balls on grass, because their masses and diameters are very different as are the counterface surfaces on which they roll.
1.1.4
Different launch ramps are appropriate for different types of spherical shapes. If a sphere of interest cannot be accommodated with using one of the launch ramps discussed in
Appendix X1 and
Appendix X2
, a different launch ramp can be developed and added with future revisions to this test method.
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
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.
====== Significance And Use ======
5.1
Rolling friction like sliding friction depends upon many factors. It is a system effect that involves the nature of the rolling surface and the counterface. The sliding friction force (
F
) is usually considered to be the sum of forces arising from deformations of surface features (
F
s
), from attractive forces (atomic, molecular, etc.) at contact points (
F
a
) and force from interaction of films and particulates on the rubbing surfaces (
F
f
):
The rolling friction force includes these force contributions plus effects from the relative stiffness of the contacting surfaces, the diameter (curvature) of the spherical shape (ball, orange, etc.) and other factors. Because there are so many factors involved in a rolling tribosystem, rolling resistance can best be quantified by an actual test of the sphere of interest on the intended counterface, as in this test method.
5.2
There are countless applications where it is important to quantify the rolling characteristics of a particular spherical shape on a particular surface. The interlaboratory tests conducted for this test method were performed on hardened steel balls like those used in ball bearings. This test method could be used to assess the effect of different counterface surfaces on the rolling characteristics of balls for ball bearings. Conversely, it could be used as a quality control test on balls. Surface imperfections/defects/films, etc. on the balls can affect how they roll: the distance traveled on a common counterface.
5.3
Industrial applications of this test method can include assessing conveying surfaces for spherical or nearly special parts: check valve balls, cabinet knobs, Christmas ornaments, toilet floats, etc. Many medical devices use special shapes where rolling characteristics are a consideration. Similarly, many pharmaceutical products (pills) are spherical or nearly spherical in shape, and this test method can be used to assess rolling characteristics for conveying or other reasons such as size (mass) check.
5.4
Rolling friction of spherical shapes can be a consideration in countless sports (soccer, golf, lacrosse, etc.) and game applications (billiards, bocce, toys, etc.). This test method can be used to rank the rolling resistance of different ball compositions, masses, shapes, surface textures, design, stiffness, etc. Similarly, the test method can be used to assess the ease of rolling of balls on different playing or game surfaces.
5.5
This test method is very applicable to spherical or mostly spherical food products. For example, it is common to use rolling distance of apples, citrus, nuts, etc. to classify them by size for marketing. They are rolled down an angled surface and the rolling distance becomes a function of size (mass/diameter). This test method can be used to assess the suitability of various rolling surfaces (carpet, metal, wood, etc.) for suitability in classification equipment. It could also be used for food conveyance on spherical-shaped processed foods (gumballs, hard candy, meatballs, etc.)
5.6
Finally, this test method can be a valuable teaching tool for physics and tribology students. The equipment is simple, low cost and student proof. It can be used to demonstrate the concept of rolling friction and the factors that affect it.