1. Product Introduction
The Inside Micrometer is a universal inside dimensional measuring tool that uses the principle of a pair of screws to read the distance between spherical measuring surfaces at both ends of the main body. It is especially suitable for measuring the inner diameter, groove and distance between two parallel planes in mechanical processing. The measured accuracy level is generally IT8-IT10 as specified in GB/T1800.3-1998.
The center of the inside micrometer measuring head is coated with hard alloy sheet, which prolongs the service life of the inside micrometer.
The internal micrometer drive mechanism is composed of a micrometer screw and a threaded shaft sleeve fixed to the fixed sleeve; the differential, calibration nut and micrometer screw are fixed together as moving parts; The measuring head, shaft threaded sleeve, fixed sleeve, etc. are connected as a fixed part. The inside micrometer has a compact structure and stable and reliable measurement accuracy.
All accuracy indicators meet national standards.
Users can choose the appropriate micrometer based on their measurement needs or place special orders according to their needs. Specific specifications and grading values are shown in Table 1.
table 1
| Series and indicators | Lower measurement limit | |||
| 50 | 150 | 250 | Individual inner diameter | |
| Micrometer head measuring range | 13 | 25 | 50 | 25 |
| Graduation fee | 0.01 | 0.01 | 0.01 | 0.01 |
| Specification (measuring range) | 50-250 50-600 50-1000 50-1500 |
150-1500 150-2000 150-3000 |
250-2000 250-3000 250-4000 250-5000 250-6000 |
50-75 75-100 275-300 |
2. Structural Diagram
- 1. Measuring contact
- 2. Connecting sleeve
- 3. Measuring head
- 4. Threaded shaft sleeve
- 5. Locking screw
- 6. Fixed sleeve
- 7. Differential
- 8. Calibration nut
- 9. Micrometric screw
- 10. Measuring head
- 11. Connecting Rod
- 12. Calibration tweezers
3 . Technical Data
| Technical Data | ||||||
| Measuring range | 50~75 | 75~125 | >125~200 | >200~325 | >325~500 | >500~600 |
| Graduation fee | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 |
| Indication error | ±0.006 | ±0.006 | ±0.008 | ±0.010 | ±0.012 | ±0.016 |
| Measure the spherical radius of the surface | 20 | 20 | 20 | 20 | 20 | 20 |
| The range of the micrometer screw is 13 | ||||||
| Check card size and deviation within 50 ± 0.002 | ||||||
4. Instructions for use
Observe whether there are any defects in the appearance of the Inside Micrometer that could affect the measurement. Clean the measuring contacts, measuring heads and measuring heads, rotate the differential to check that it rotates flexibly, and check that the locking device is firmly fixed.
Before using the Inside Micrometer, use the calibration clamp to calibrate the zero position of the micrometer head (combination of 3 to 9 components) and apply uniform force.
If there is a small error, first tighten the locking screw, then loosen the calibration nut to align the zero position of the differential cylinder with the longitudinal line of the fixed sleeve, and finally tighten the calibration nut.
When connecting the connecting rod to the inside micrometer during use, first unscrew the nut on the shaft threaded sleeve, and then screw the right end of the connecting rod into the left end of the shaft threaded sleeve.
When using the inside micrometer to measure the opening, rest the measuring surface of the measuring contact on the measuring surface, adjust the differential and rotate the measuring surface on one side of the differential cylinder in the radial section of the hole to find the maximum size, and then then rotate it in the axial section of the hole to find the minimum size. This adjustment needs to be repeated several times.
Finally, tighten the locking screw, remove the inside micrometer and read the measurement. When measuring the distance between two parallel planes, rotate the inside micrometer in several directions and take the smallest size as the measurement result.
5. Precautions
The Inside Micrometer not only can be used with a connecting rod for measuring inner diameter and internal dimensions, but the micrometer head (combination of 3-9 components) can also be used as a single Inside Micrometer.
When using the Inside Micrometer, select the appropriate connecting rod from the connecting rod comparison chart provided to form the required size to reduce cumulative errors. In addition, connect the largest connecting rod to the micrometer head, and then sequentially connect it to the measuring contact to reduce shaft bending after connection.
When using the Inside Micrometer to measure the opening, at least one cross section must be measured in two perpendicular directions. For deep hole measurements, the number of support faces must be increased accordingly.
Pay attention to the influence of temperature during measurement and avoid heat transfer from hands or other heat sources. Especially for large measurements, special attention must be paid.
The supporting position of the Inside Micrometer during measurement must be correct. When measuring with a long-length Inside Micrometer, support it at 0.211L on both ends of the overall size. This reduces deformation and minimizes measurement errors.
After measurement, the Inside Micrometer must be placed horizontally to avoid deformation of the instrument.
During use, be careful not to hit the micrometer. Before assembling the connecting rod, clean all contact and measuring surfaces. After use, apply rust-proof oil to each measuring surface and store them in a box.
Connecting rod comparison table is attached below.
Except for the measuring range (50-70) mm, all other components are connected to the micrometer head with a connecting sleeve.
| Comparison Table for Inside Diameter (50-600)mm Micrometer Extension Rod | |||||||||
| Measuring range mm |
Micrometric head 50mm |
Measuring contact 13mm |
Measuring head 20mm |
NQ1 extension rod 13mm |
NQ2 extension rod 25mm |
NQ3 extension rod 50mm |
NQ4 extension rod 100mm |
NQ5 extension rod 150mm |
NQ6 extension rod 200mm |
| 50~63 | 1 | – | – | – | – | – | – | – | – |
| 63~70 | 1 | ||||||||
| 70~83 | |||||||||
| 83~95 | 1 | ||||||||
| 95~108 | – | 1 | |||||||
| 108~120 | 1 | ||||||||
| 120~133 | – | – | 1 | ||||||
| 133~145 | 1 | ||||||||
| 145~158 | – | 1 | |||||||
| 158~170 | 1 | ||||||||
| 170~183 | 1 | – | 1 | – | – | – | 1 | – | – |
| 183~195 | 1 | ||||||||
| 195~208 | – | 1 | |||||||
| 208~220 | 1 | ||||||||
| 220~233 | – | – | – | 1 | |||||
| 233~245 | 1 | ||||||||
| 245~258 | – | 1 | |||||||
| 258~270 | 1 | ||||||||
| 270~283 | – | – | – | 1 | |||||
| 283~295 | 1 | ||||||||
| 295~308 | – | 1 | |||||||
| 308~320 | 1 | ||||||||
| 320~333 | 1 | – | 1 | – | – | 1 | – | – | 1 |
| 333~345 | 1 | ||||||||
| 345~358 | – | 1 | |||||||
| 358~370 | 1 | ||||||||
| 370~383 | – | – | – | 1 | |||||
| 383~395 | 1 | ||||||||
| 395~408 | – | 1 | |||||||
| 408~420 | 1 | ||||||||
| 420~433 | – | – | – | 1 | |||||
| 433~445 | 1 | ||||||||
| 445~458 | – | 1 | |||||||
| 458~470 | 1 | ||||||||
| 470~483 | 1 | – | 1 | – | – | 1 | – | 1 | 1 |
| 483~495 | 1 | ||||||||
| 495~508 | – | 1 | |||||||
| 508~520 | 1 | ||||||||
| 520~533 | – | – | – | 1 | |||||
| 533~545 | 1 | ||||||||
| 545-558 | – | 1 | |||||||
| 558~570 | 1 | ||||||||
| 570~583 | – | – | 1 | ||||||
| 583~595 | 1 | ||||||||
| 595~608 | – | 1 | |||||||
