FCJ 21-1995千分尺校准方法( FOR CALIBRATION OF MICROMETER).doc

FCJ 21-1995 共 1 页 第 1 页PAGE 1 OF 1 成都飞机工业（集团）有限责任公司企 业 标 准CHENGDU AIRCRAFT INDUSTRIAL (GROUP) COMPANY LIMITEDENTERPRISE STANDARD FCJ 21-1995千分尺校准方法METHOD FOR CALIBRATION OF MICROMETER共 23 页 23 PAGES更改单记录Record of Change Sheet更改单编号Change Sheet No.接收人Receiver日期Date备注Remarks FCJ 21-1995 共 21 页 第 21 页PAGE 21 OF 211.范围Scope本标准规定了千分尺，包括公制和英制外径千分尺、数显千分尺及板厚千分尺、壁厚千分尺、锥测头千分尺的要求、校准条件、校准项目及校准方法、校准结果的处理和校准周期。This standard specifies the requirements, calibration terms, calibration items, calibration methods, calibration result handling and calibration periodic time of micrometers, including metric system and British system external micrometers, digimatic micrometers, slab thickness micrometers, arm thickness micrometers, and conical gauge head micrometers., 本标准适用于使用中和修理后表1所列规格的外径千分尺、数显千分尺及板厚千分尺、壁厚千分尺、锥测头千分尺(公英制)的校准。This standard is applicable for the calibration of the following micrometers in use and repaired, including metric system and British system external micrometers, digimatic micrometers, slab thickness micrometers, arm thickness micrometers, and conical gauge head micrometers.表1 各规格千分尺的主要技术指标序号测量范围mm平行度允差mm示值误差允许值mm102524225502.54350100344100150455150200666200300777300400_88400500_109500600_3 or 510600700_11700800_12800900_139001000_注1：当测微头的示值范围为25mm时，示值误差应不超过3mm。注2：当测微头的示值范围为50mm时，示值误差应不超过5mm。Table 1 The main technical index of micrometers in various specificationsS/N.Scope of measurementmmParallelism tolerancemmIndication deviation allowablemm102524225502.54350100344100150455150200666200300777300400_88400500_109500600_3 or 510600700_11700800_12800900_139001000_Note 1: when indication scope of micrometer head be 25mm, indication deviation shall be within 3mm.Note 2: when indication scope of micrometer head be 50mm, indication deviation shall be within 5mm.2.规范性引用文件Referenced Normative Documents本章无条文。N. A.3.术语、符号Terminologies and Symbols本章无条文。N. A.4.概述General千分尺是由尺架、尺砧、测微螺杆、测力装置和锁紧装置等组成。千分尺是应用螺旋副传动的一种量具，主要用于测量各种外尺寸。Micrometer is composed of stand, anvil, micrometric screw, force device, locking apparatus, etc. Micrometer, a measuring implement drove by screw pair, shall be mainly for measuring all external dimensions.5.要求Requirements5.1外观Appearance被校千分尺不应有影响使用准确度的外观缺陷，如：碰伤、锈蚀等。Micrometers calibrated shall be without macroscopic irregularities which will influence using accuracy, for instance, bumping damage, rust-eaten, etc.5.2各部分相互作用及相对位置Interactivity and Relative Position of All Parts. 5.2.1各部分相互作用应灵活、可靠，可换或可调测砧的装卸或调整应顺畅，锁紧装置的作用应切实有效。Interactivity of all parts shall be flexible and credible; loading and discharging or adjustment of anvil changeable or adjustable shall be smooth; the effect of locking apparatus effective.5.2.2当微分筒零刻线与固定套管纵刻线对准时，微分筒锥面的端面与固定套管毫米刻线的右边缘应相切，不应有很明显的离压线(即压线不大于0.05mm，离线不大于0.1mm)。In case of microdrum zero scratch and fixed spigot longitudinal scratch matching each other, the surface of microdrum pyramidal face shall be tangential with the right edge of fixed spigot metric scratch; no obvious off line and press line be allowable, that is, press line no longer than 0.05mm and off line no longer than 0.1mm.5.3测量面的平面度Flatness of Measuring Planesa) 平面度误差应不大于1mm；Flatness deviation shall be within 1mm;b) 壁厚千分尺的平面度误差应不大于1.2mm；Flatness deviation of arm thickness micrometers shall be within 1.2mm;c) 锥测头千分尺不作此项校准。This calibration shall be not applicable for conical gauge head micrometers. 5.4两工作面的平行度 Parallelism of Two Acting Surfaces.a) 两测量面的平行度误差要求见表1；Table 1 refers to the parallelism deviation of two measuring planes;b) 板厚千分尺、壁厚千分尺、锥测头千分尺可不作此项校准。This calibration shall be not applicable for slab thickness micrometers, arm thickness micrometers, and conical gauge head micrometers.5.5示值误差Indication Deviation示值误差要求见表1。Refer to Table 1 for indication deviation.5.6校准用量杆实际尺寸和两测量面的平行度Actual Size of Measuring Rod for Calibration and Parallelism of Two Measuring Planes.a) 校对用量杆的实际尺寸对其标称尺寸的偏差要求见表2。校准量杆按实际工作尺寸使用。(当校对量杆的实际尺寸对其标称尺寸的偏差超过0.01mm时，应予以报废)；Table 2 refers to the deviation of actual size of measuring rod for calibration against its nominal dimension. Measuring rod for calibration shall be applied as per the actual working size. (Discard the measuring rod for calibration in case that the deviation of actual size of it against its nominal dimension being over 0.01mm);b) 校对用量杆的平行度误差要求见表2。Table 2 refers to the parallelism deviation requirements of measuring rod for calibration.表2 校对用量杆尺寸偏差和两工作面的平行度校对用量杆的标称尺寸mm尺寸偏差mm工作面的平行度mm252150217521.5100125 2.5215017532.5200225 3.53.5250275 3.53.53253754442547555Table 2 Size deviation of measuring rod for calibration and parallelism of two working planesNominal dimension of measuring rod for calibration mmSize deviationmParallelism of acting surfaces.m252150217521.5100125 2.5215017532.5200225 3.53.5250275 3.53.532537544425475556.校准条件Conditions for Alignment6.1环境条件Environmental Conditions-校准间温度和受校千分尺及校准用量具在室内衡温时间要求见表3；Refer to Table 3 for time requirements in room temperature of calibration temperature, calibrated micrometers and measuring rod for calibration.-电源要求：交流220V，50Hz。 Requirement for electric source: alternate current 220V, 50Hz.表3 校准温度及衡温时间要求受校千分尺测量范围校准间温度平衡温度时间千分尺校对杆0100 (20 5)C(20 3)C2h100500(20 4)C(20 2)C3h5001000(20 3)C(20 2)C4hTable 3 Time requirements of calibration temperature and equilibrium temperature Measuring range of calibrated micrometersTemperature of calibrationEquilibrium temperature timeMicrometerMaster rod0100 (20 5)C(20 3)C2h100500(20 4)C(20 2)C3h5001000(20 3)C(20 2)C4h6.2建议使用的标准/设备Standard or Equipment for Suggestion建议使用的标准/设备见表4。Refer to Table 4 for standard or equipment for suggestion.表4 建议使用的标准/设备序号标准或设备名称型号或规格技术指标11级刀口尺175mm直线度1.5mm24等量块5.12500mmU=(0.20+2L)mm，K=2.58，L为所用量块的长度，单位为m。3立式光学计JD3示值误差：0.25mm4卧式测长仪JD5(1+ L /100) mm5测长机光学计管示值误差：0.25mm. Table 4 Standard or equipment for suggestionS/ N.Standard or description of equipment Model or specificationQualification index1Knife-edge measuring tape of grade 1175mmStraight-line degree1.5mm2Four equivalent parts5.12500mmU=(0.20+2L)mm, K=2.58,L refers to the length of measuring part, unit: m.3Vertical optimeterJD3Indication deviation: 0.25mm4Horizontal length measuring instrumentJD5(1+ L /100) mm5End measuring machineIndication deviation of optimeter tube : 0.25mm7.校准项目及校准方法Calibration Items and Methods7.1校准项目Calibration Items校准项目见表5。 Refer to Table 5 for calibration items. 表5 校准项目序号校准项目适用于使用中修理后1外观+2各部分相互作用及相对位置+3测量面的平面度+4两工作面的平行度+5示值误差+6校对用量杆+注：表中“+”表示应校准。Table 5 Calibration itemsS/ N.Calibration itemsApplicable forIn serviceRepaired1Appearance+2Interactivity and relative position of all parts.+3Flatness of measuring plane+4Parallelism of two acting surfaces.+5Indication deviation+6Measuring rod for calibration+Note: “+” in table indicating calibration necessity.7.2校准方法Calibration Methods7.2.1外观 Appearance目力观察，应符合5.1的要求。Visual Observation shall meet the Specifications in 5.1.7.2.2各部分相互作用及相对位置 Interactivity and relative position of all parts.目力观察与实验，应符合5.2的要求。Visual observation and experiment shall be in line with the requirements in 5.2.7.2.3测量面的平面度 Flatness of measuring plane用刀口尺以光隙法校准。其误差不超过5.3的要求。Calibrate with Knife-edge measuring tape by light gap method. Deviation shall be in conformity with requirements of 5.3.7.2.4两工作面的平行度 Parallelism of two acting surfaces.用4等量块尺寸约为千分尺微分筒1/4螺距的4块量块进行校准。每块量块以其同一部位放入千分尺测量面(见图1)的四个位置上，分别读出一组数，并求出其差值，以四组差值中最大值作为千分尺两测量面的平行度误差。其值应符合表1的要求。Calibrate with 4 equivalent measuring parts sized as 1/4 of thread pitch of micrometers microdrum. Put the same position of each measuring parts on the four locations of micrometer measuring plane (see Fig. 1), read out a series of number and figure out the difference values, then take the max. value of the four groups as the parallelism deviation of two measuring planes of micrometers. The value shall be in conformity with the requirements of Table 1.1/4D1234壁厚千分尺、板厚千分尺、锥测头千分尺不做此项校准。This calibration shall be not applicable for slab thickness micrometers, arm thickness micrometers, and conical gauge head micrometers.图1 量块测量位置示意图Fig.1 Measuring location diagrammatic sketch of the measuring parts7.2.5示值误差Indication deviation用4等专用量块在千分尺测量范围内均匀分布作不少于5点的校准。在每个校准点上作3次校准，3次读数的平均值与量块实测尺寸之差为该点的示值误差。各受校点的示值误差应符合表1的要求。示值误差按公式(1)计算：Calibrations shall be taken on at least 5 points evenly distributed in the measuring range of micrometers with four specific equivalent measuring parts. Three times of calibration shall be taken on each calibrating point; the indication deviation of this point shall be the difference of the mean value of three readouts and the actual measurement size of the measuring part. Indication deviation of each calibrated point shall be in conformity with the requirements of Table 1.Indication deviation shall be calculated by formula (1): i= Qi Li (1)式中Thereinto:i - 各校准点的示值误差，单位为毫米(mm)；Indication deviation of each calibrated point, unit: mm;Qi - 千分尺各校准点的读数，单位为毫米(mm)；Readouts of each calibrated point of micrometers, unit: mm;Li - 各校准点所用相应量块的实际尺寸，单位为毫米(mm)。Actual size of relevant measuring parts for each calibrated point, unit: mm;注：当千分尺测量范围大于500mm时，必须在两工作面平行度合格的情况下，按7.5的方法作测微头示值范围的校准。Notes: when the measuring range of micrometers being over 500mm, calibration of indication scope of micrometer head must be taken as per the method of 7.5, on the condition that parallelism of the two working planes be acceptable.7.2.6校对用量杆(以下简称量杆)实际尺寸和两测量面的平行度 Actual size of measuring rod for calibration, hereinafter called rod, and the parallelism of the two measuring planes.在立式光学计或测长机上用4等量块以比较法进行校准时，对平工作面的量杆采用球面测帽在仪器上用相应的量块对零，然后在量杆上作如图2所示的5点进行测量。5点中最大值与最小值之差为量杆两工作面的平行度误差，最大值加量块实际尺寸为量杆的实际尺寸。对于球工作面的量杆，应用8的平面测帽进行比较测量，量杆实际尺寸和两测量面的平行度误差应符合表2得要求。Calibrating with 4 equivalent measuring parts on vertical optimeter and end measuring machine by comparison method, for rod on even working plane, zero with relevant measuring parts on the device by spherical survey cap, then take measurement at the 5 points indicated in Fig.2 on the rod. The parallelism deviation of two working planes shall be the difference of the max. value and the min. value among that of the five points. The max value adding to the actual size of measuring part shall be the actual size of rod. For rod on spherical working plane, comparatively measure it with8 plain survey cap; the actual size of rod and the parallelism deviation of two measuring planes shall be in conformity with the requirements of Table 2.142 35图2 校对量杆的测量位置Fig.2 Measuring places of calibrated rod.7.3不确定度的分析Analysis of Uncertainty - 千分尺示值校准的测量不确定度见附录A；Refer to Appendix A for the uncertainty of calibrating measurement of micrometer indication value; - 千分尺校对用量杆实际尺寸测量的不确定度分析见附录B。Refer to Appendix B for the uncertainty analysis of actual size measurement of rod for micrometer calibration.8.校准结果的处理和校准周期Treatment of Alignment Results and Alignment Periodicity8.1记录Recording千分尺的校准结果应在量表109千分尺校准原始记录上进行记录（版次见FCT计量-目-01）。Calibration result of micrometers shall be recorded in form 109 （edition: see catalogue file FCT Metrology Catalogue 01 ）. 8.2标记与证书Labels and Certificates8.2.1经校准符合本校准方法要求的千分尺应粘贴相应的合格标记。The micrometers calibrated and qualified for the requirements shall be stuck with relevant qualification labels. 8.2.2经校准不符合本校准方法要求的千分尺，应进行修理。修理后经校准仍不合格则予以报废。Repair calibrated micrometers that fail to follow the requirements of calibration method. Discard those still unacceptable after repair.8.3校准周期Alignment Periodicity千分尺校准周期可根据具体使用情况而定，一般不得超过一年。The alignment periodicity of micrometers can be set as per specific service condition, but generally within one year.附录A Appendix A(规范性附录)Normative 千分尺示值校准的测量不确定度The uncertainty of calibrating measurement of micrometer indication value A.1校准方法说明Description of Alignment Method千分尺示值的校准是用4等专用量块以比较法进行测量的。根据本校准方法给出示值误差的计算公式(A.1)：Alignment of micrometer indication value shall be taken with 4 equivalent specific measuring parts by comparison method. Formula (A.1) of calculating indication deviation according to this calibration method: i = Qi Li (A.1)式中Thereinto:i - 各校准点的示值误差，单位为毫米(mm)；Indication deviation of each calibrated point, unit: mm;Qi - 千分尺各校准点的读数，单位为毫米(mm)；Readout of each calibrated point of micrometers, unit: mm;Li- 各校准点所用相应量块的实际尺寸，单位为毫米(mm)。Actual size of relevant measuring parts for each calibrated point, unit: mm;A.2不确定度影响因素及说明Factors influencing the uncertainty and descriptions除Li、Qi两项会引入不确定度外，还有千分尺测量面的平面度、平行度引入的不确定度，以及测量重复性引入的不确定度。In addition to the uncertainties introduced by Li and Qi, still there shall be the uncertainties introduced by the flatness and parallelism of micrometer measuring plane, and the repeatability of measurement.另外，由于千分尺的校准工作在本标准规定的校准条件下，是用比较法进行测量的，故由温度引起的不确定度很小，可忽略不计。Further more, because of micrometers calibration being measured by comparative method under such circumstances specified in this standard, uncertainty caused by temperature change, which be very tiny, might be ignored. A.3不确定度的计算及表达 Calculation and Description for Uncertainty A.3.1不确定度的计算 Uncertainty calculation 由于上述影响因素相互独立不相关，所以合成标准不确定度按公式(A.2)计算：Due to the irrelevancy of the above mentioned influences, the uncertainty of combined standard might be calculated by the following formula (A.2): = (A.2)式中Thereinto: u1 - 4等专用量块引入的不确定度；Uncertainty introduced by 4 equivalent specific measuring parts; u2 - 被校千分尺各校准点读数引入的不确定度；Uncertainty introduced by readout of each calibrated point of the calibrated micrometer; u3 -测量面平面度引入的不确定度； Uncertainty introduced by flatness of measuring plane; u4 -两测量面平行度引入的不确定度； Uncertainty introduced by parallelism of two measuring planes; u5 -测量重复性引入的不确定度。 Uncertainty introduced by test. A.3.2各分量评定的详细说明 Specific Description of Evaluation for Each ConstituentA.3.2.14等专用量块引入的不确定度u1 Uncertainty introduced by 4 equivalent specific measuring parts u1;量块中心长度测量的不确定度为U=(0.2+2L)mm，k=2.58；则：Measuring uncertainty of the central length of measuring parts being U= (0.2+2L)mm, k=2.58;then:u1= (0.2+2L)/2.58 (mm ) .注：L为所用量块的长度，单位为米(m)。Notes: L indicates the length of measuring part, unit: m.A.3.2.2被校千分尺各校准点读数引入的不确定度u2. Uncertainty introduced by readouts of each calibrated point of the calibrated micrometer, u2;在千分尺示值校准时的读数可读到分度值的1/10，其区间半宽度为1mm，估计其为均匀分布，k=，则：u2=1/=0.58(mm)。Readouts of calibrating indication of micrometers might be 1/10 of the division value, interval semi-breadth being 1mm, estimated as even distribution, k=, then: u2=1/=0.58(mm).A.3.2.3测量面平面度引入的不确定度u3 Uncertainty introduced by flatness of measuring plane u3;由5.3得出平面度的允许极限误差为面，其区间半宽度为面/2估计为正态分布，取k=3，因有两个面的平面度影响，故 u3=(面/2k)=(面/6). According to 5.3, the limit error allowable of flatness being S, interval semi-breadth being S/2, estimated as even distribution, k=3, due to flatness influences of two sides, thus: u3=(S/2k)=(S/6).A.3.2.4两测量面平行度引入的不确定度u4. Uncertainty introduced by parallelism of two measuring planes u4;在本标准上查出测量面平行度的允许极限误差为平，其区间半宽度为平/2，估计为正态分布，取k=3，故：u4=(平/2k) =(平/6). According to this standard, the limit error allowable of measuring planes parallelism being p, interval semi-breadth being p/2, estimated as even distribution, k=3, due to flatness influences of two sides, thus: u4= (p/2k) =(p/6)A.3.2.5测量重复性引入的不确定度u5. Uncertainty introduced by test repeatability u5.在千分尺的同一点上校准，作3次等精度测量，获得单次实验标准偏差s(x)，按公式(A.3)进行计算：Conduct 3 observations of equal accuracy at the same place on the micrometer, obtain single standard deviation s(x) and calculate according to formula (A.3): s(x)=(Xmax-Xmin)/dn (A.3)式中Thereinto:s(x) -单次实验标准偏差；Single standard deviation;Xmax - 在校准点上读得的最大值；The maximum value of the calibration point;Xmin -在校准点上读得的最小值； The minimum value of the calibration point;dn - 为极差法的系数；Coefficient of deviation limit;n - 测量次数。Measuring times.当n3时，d3=1.69，由经验得(Xmax-Xmin)最大为1mm，故u5=s(x)=1/1.69=0.59（mm）。When n3,d3=1.69,according to experience, the max of (Xmax-Xmin) being 1mm, thus:u5=s(x) =1/1.69=0.59 (mm).A.3.3千分尺示值校准的扩展不确定度 The Uncertainty of Extension of Micrometer Indication Value Calibration; A.3.3.1按公式（A.2）计算合成标准不确定度。Calculation of composition standard uncertainty shall follow formula (A.2).A.3.3.2取k=2，置信水平p=95%， 则：扩展不确定度为：U=2uc. When k=2,confidence level being: p=95%, then：the uncertainty of extension being：U=2ucA.3.3.3千分尺示值校准的扩展不确定度见表A.1。Table 1 refers to the uncertainty of exte