How to verify needle rules

1、 The Use of Needle Gauges

1. Measuring aperture

2. Check the accuracy of calipers and micrometers

3. Slot width measurement

4. Rough measurement of R

5. Hole spacing measurement (auxiliary fixture)

6. Used for auxiliary fixtures, measuring hole positions, parallelism, etc

7. During processing, assist with positioning fixtures

8. Eccentricity, measurement (auxiliary fixture)

9. Auxiliary measurement of groove depth

10. Measurement of accuracy of machining machinery chucks

2、 Precautions before use:

1. Remove rust proof oil, dust, and attachments

2. Confirm for any defects, wear, or rust

3. It is necessary to remove the burrs in the hole before stopping the measurement (plastic and metal)

4. When inserting the hole, it should be inserted directly into the hole and not forcefully twisted or pressed

5. Do not take out multiple PG tubes at the same time, heterozygous mix

3、 Measurement method:

Definition of hole (slot) through stop management (common consensus):

Pass: The state in which the needle gauge passes through the hole of the component, and the component or needle gauge can fall freely and weigh itself

Stop: The state in which the component or needle gauge cannot bear its own weight and fall freely

When a nearby group of PG generates a set of on/off, record the on/off value as the aperture value

4、 Measurement precautions:

1. When PG φ＞ At 5 o'clock, PG is relatively heavy, and it is not recommended to judge based on PG falling down

2. When perforation or deep drilling is carried out, and the aperture is uneven, at least two sets of values should be measured for the upper and lower parts.

3. PG should be separated by a minimum of 0.01. When the separation is greater than 0.01, experience and feel (level of elasticity) can be evaluated to determine the pass value.

4. When customers have different detailed requests, the customer's request shall prevail.

5. When fixing the screw hole, measure the depth h ≤ 3 φ (Reason: Non functional positions in other depth holes)

6. Do not use PG to measure metal holes, especially rough holes. Processing plan for measuring metal holes: Purchase and use special PG (ultra hard type), and confirm the use of unused top pins for the top pin holes.

5、 Precautions after using needle gauges:

1. Fine needle gauge, pay special attention when using, do not bend or fall

2. When working in the center of the workbench, do not let the PG slide and fall to the ground

3. After use, put it into a small bottle with anti rust oil

4. On the standard line, gloves should be worn to operate PG