JJF 1140-2006Calibration Specification for Square Testers (English PDF)

1 Scope (1)

2 Citations (1)

3 Overview (1)

4 Measurement characteristics (3)

5 Calibration conditions (3)

6 Calibration items and calibration methods (4)

7 Calibration result expression (7)

8 Re-study interval (7)

Appendix A Measurement Uncertainty Analysis of Calibration Results of Right Angle Inspection Instrument (8)

Appendix B Example of calculating the flatness of the work surface (14)

Appendix C Outline and technical requirements of standard squares (15)

Appendix D Calibration Certificate Content Requirements (16)

Square ruler calibration specification

1 Scope

This specification applies to the calibration of the square ruler.

2 Citations

This specification refers to the following documents.

JJF 1001-1998 General measurement terms and definitions JJF 1059-1999 Measurement Uncertainty Evaluation and Representation JJF 1094-2002 Technical Specifications for Measuring Instrument Characteristics JB/T 10015-1999 square ruler JJG39-2004 mechanical comparator verification procedures JJG117-2005 plate verification procedure JJG118-1996 Torsion spring type comparator verification procedure JJG396-2002 Inductance Micrometer Calibration Procedure Use of this specification should be done with the current valid version of the above cited documents.

3 Overview

The square ruler uses a comparative measurement method or a direct measurement method for measuring accuracy levels of 0 and below.

The perpendicularity of the square. The square ruler can also be called a square ruler, a verticality tester, and the like.

The form and basic parameters of the square ruler are shown in Table 1.

Table 1 Form and basic parameters of the square ruler

No. Basic parameters I type right angle ruler type II right angle ruler

1 Measuring range (63~1000)mm (63~500)mm

2 Measure the accuracy of the square at level 0, level 1, level 2

3 The aperture of the clamp indicator is phi8mm or phi28mm

4 Measurement method Fixed measurement Continuous measurement

5 Indexing scale value <= 0.001mm 6 indicator range of indication range ±0.05mm Type I square ruler (common shape is shown in Figure 1). The table is fixed at the left and right ends or one end is fixed.

Fixed, one end adjustable, the instrument has a reversing device. Type II square ruler (common shape as shown in Figure 2) the table is a one-piece type, and the instrument has no reversing device.