GB/T 1216-2018External micrometer (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009. This standard replaces GB/T 1216-2004 "outer diameter micrometer". This standard is compared with GB/T 1216-2004, except for editorial modifications. In addition, the main technical changes are as follows:

--- Scope of application removed the outer diameter micrometer with a graduation value of 0.005mm (see Chapter 1, Chapter 1 of the.2004 edition);

--- Modified the definition of the outer diameter micrometer (see 3.1,

3.1 of the.2004 edition);

--- Increased the type of outer diameter micrometer (see 4.1.1);

--- Increased the type and description of the outer diameter micrometer reading device (see 4.1.2);

--- Modified the basic parameters of the outer diameter micrometer (see 4.2,.2004 version 4.2);

--- Modified the deformation requirements of the ruler (see 5.3.1,

5.3.1 of the.2004 edition);

---Modified the technical requirements for micrometer screw and anvil (see 5.4,.2004 edition 5.4);

--- Revised the technical requirements for interaction (see 5.5,

5.5 and Appendix A of the.2004 edition);

---Modify the "force measuring device" as "locking device" (see 5.6,

5.6 of the.2004 edition);

1 Scope

GB/T 1216-2018 is the Chinese national standard on external micrometer, in the field of metrology and measurement. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 14 May 2018 by the State Administration for Market Regulation; Standardization Administration of China, and has been in force since 1 December 2018. Classification: ICS 17.040.30, CCS J42. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

c) Anvil can adjust the position (or movable) outer diameter micrometer Description. 1

---measurement surface; 2

---micrometer screw; 4

---foot frame; 5

---insulation device; 6

---locking device; 7

---fixed casing; 8

--- ruler analog reading device; 10

---microtube; 11

---force measuring device; 12

---counter digital reading device; 13

---replaceable anvil; 14

---Adjustable position (or movable) anvil. Figure 1 (continued)

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article. Pieces. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 1800.2-2009 Geometrical Product Specifications (GPS) Limits and fits. Part 2. Standard tolerance classes and Limit deviation table

GB/T 17163-2008 Geometric quantity measuring instrument terminology basic terminology

GB/T 17164-2008 Geometric quantity measuring instrument terminology product terminology

3 Terms and definitions

The following terms and definitions as defined in GB/T 17163-2008 and GB/T 17164-2008 apply to this document.

3.1 Using the screw pair to convert the rotation angle of the micrometer screw into the axial displacement of the micrometer screw, and the distance between the two measuring surfaces on the scale frame An external measuring device that performs readings.

Note. Rewrite GB/T 17164-2008, definition 2.3.2.

3.2 Micrometer maximum allowable error maximumpermissibleerrorofmeasuringhead The influence of the anvil and the ruler is neglected, and only the maximum allowable error of the indication of the micrometer is specified.

5 Basic dimensions of the outer diameter micrometer Table

1 Basic dimensions are in millimeters Basic size nominal value The nominal diameter of the portion of the micrometer screw and the anvil that protrudes from the frame, D1a 5, 6.35, 6.5, 7.5,

8.0 The length of the anvil is extended by the frame, L1 >=

3 Measuring the length of the micro screw protruding from the frame at the upper limit of the measuring range, L2 >=

3 Upper limit of measuring range of outer diameter micrometer, L3 <=1000 The range of the outer diameter micrometer, L4a 13,15,25,

50 Ruler depth, L5 >= 0.5 × L

3 The outer diameter micrometer micrometer screw pitch a 0.5,1 a Manufacturer may choose other parameters.

5.1 Appearance The outer diameter micrometer should not have defects such as rust, bumps, scratches, cracks, etc. that affect the performance.

6 Test methods

6.1 Scale deformation Fix the end of the ruler to measure the anvil, apply 100N force to the end of the micro-screw of the ruler, and observe the force under the applied and unstressed conditions respectively. The generated indication value is converted into a ratio of 10N force by the difference between the secondary indication values, and the amount of deformation of the frame is obtained.

6.2 Measuring plane flatness When using 2-level optical flat crystal inspection, the optical flat crystal should be adjusted so that the number of interference bands or interference rings on the measuring surface is as small as possible, or A closed interference ring is produced, and two or more interference rings or interference bands of the same color should not appear on the measurement surface. The flatness within

0.4 mm from the edge of the measuring surface is ignored.

6.3 Parallelism of the measuring surface The outer diameter of the measuring range is not more than 100mm. The parallelism of the two measuring surfaces should be three or four, and the thickness is poor. An optical parallel flat crystal approximately equivalent to 1/3 or 1/4 of the pitch of the micrometer screw is tested; the optical parallel flat crystals are sequentially placed into two measurements Face, turn the force measuring device, apply a force of 5N~10N, make the optical parallel flat crystal and the measuring surface contact, and gently rotate the flat crystal to make two measurements The number of interference rings or interference bands present on the measuring surface is minimized. The parallelism of the outer diameter micrometer measuring surface can also be checked with other instruments (such as a self-collimator). Parallelism in the range of

0.4 mm from the edge of the measuring surface is ignored.

6.4 Interaction Under normal circumstances, the interaction is checked by hand, and the hand feel must not have obvious axial turbulence and radial oscillation; if there is any objection, the following can be Method test. Check the axial yaw with a lever indicator with a resolution of not less than

0.001 mm. Connect the lever indicator to the micrometer screw when testing. At the touch, a force of 3N~5N is applied back and forth along the axial direction of the micrometer screw, and the change of the indication value of the indication table is the axial turbulence of the micrometer screw. Check the radial swing with a lever indicator with a resolution of not less than

0.001 mm. When testing, the micro screw is extended by 10 mm to make the bar. The rod indicating table contacts the end of the diameter of the micrometer screw, and applies a force of 2N~3N to the measuring direction of the lever indicator on the micrometer screw, The change in the display value is the amount of radial swing of the micrometer screw in this direction. The test of radial oscillation should be in two mutually perpendicular directions In the row, the maximum value obtained by taking the test twice is the radial swing amount of the micro screw.

6.5 hardness For measuring surfaces without cemented carbide or other wear-resistant materials, a smooth cylindrical part of 1 mm from the measuring surface or from the measuring surface Inspection. For measuring surfaces with cemented carbide or other wear-resistant materials, the hardness can be checked.

6.6 Measuring surface deviation Under normal circumstances, the two measuring surfaces of the outer diameter micrometer should not be obviously deflected by eyesight; if there is any objection, it can be tested as follows: The deviation of the two measuring faces is checked with a indicating table having a resolution of not less than

0.01 mm or a height caliper. When testing, first measure the outer diameter micrometer The micro-screw is adjusted to the maximum range, and then the ruler is placed flat on the three adjustable support frames on the flat plate, and the support frame is adjusted to extend the micrometer screw The axis is parallel to the plane of the plate, and the distance between the micrometer screw and the anvil to the flat plane is measured respectively. The difference between the two distances is that the two measuring surfaces are horizontal. The offset of the direction; then, the scale is rotated 90° around the axis of the micrometer screw, so that the plane of the ruler is perpendicular to the plane of the plane, and the frame is used as a support point. Tune The whole support point makes the axis of the extension part of the micrometer screw parallel to the plane of the flat plate, and respectively measures the distance between the micrometer screw and the anvil to the flat plane, two distances The difference between the two is the offset of the two measuring faces in the vertical direction; the maximum value obtained by the two tests is the offset of the two measuring faces.

6.7 indication error

6.7.1 Fasten the outer diameter micrometer to the fixture and place the dimension series between the two measuring surfaces. A 2.5mm, A 5.1mm, A 7.7mm, A 10.3mm, A 12.9mm, A 15mm, A 17.6mm, A 20.2mm, A 22.8mm and A 25mm or size series. A 5.12mm, A 10.24mm, A 15.36mm, A 21.5mm, A 25mm The level 2 precision gauge block is checked (A is to achieve the lower limit of the measurement range). Measure the deviation of the outer diameter micrometer indicator value from the size of each gauge block. The deviation of each point of the connection is plotted as a curve, and the absolute value of the difference between the coordinates of the highest point and the lowest point on the ordinate is the indication of the outer diameter micrometer. See Figure 6 for the error. Description. L

---indicator error; c

7 Signs and packaging

7.1 The outer diameter micrometer shall be marked with.

a) manufacturer's name or trademark;

b) the division value or resolution;

c) measurement range;

d) Product serial number.

7.2 The proof gauge shall be marked with its nominal length.

7.3 The outer diameter micrometer box should be marked with.

a) manufacturer's name or trademark;

b) product name;

c) measurement range;

d) Grading value or resolution.

7.4 The outer diameter micrometer should be rust-proofed and properly packaged before packaging, and the product should not be damaged during transportation due to poor packaging.

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