The dial bore gauge is a precise measuring tool, widely used in mechanical processing and quality control fields.
This article will provide you with a detailed analysis of the extension amount of the measuring rod of the dial bore gauge,
as well as how to ensure accurate measurement. It will elaborate on the significance and related technical details
of this issue from multiple perspectives.
I. Structure and Principle of the Measuring Rod of the Micrometer Dial Gauge
The core component of the dial bore gauge is the measuring rod, which directly affects the accuracy and range
of the measurement. The movable measuring head on the measuring rod is the key part for achieving
precise measurement. Let's delve into its structure:
1. The measuring rods are usually made of high-strength alloy steel and their surfaces are hardened to ensure
wear resistance and stability.
2.The measuring probe is installed at one end of the measuring rod and can move along the axial direction.
This movement is the extension/contraction amount.
3. The interior of the measuring rod is equipped with a precise mechanical transmission device,
which converts the displacement of the measuring head into readable values.
II. The extension amount of the measuring rod of the dial bore gauge
The extension amount of the movable measuring tip of the internal diameter gauge is usually between 5mm and 10mm.
This range has been carefully designed to balance measurement accuracy and applicability:
1. The common internal diameter micrometer has a measuring rod that can extend or retract by 6mm or 8mm.
2. The high-precision models may have a smaller expansion and contraction range, such as 5mm,
in order to enhance the accuracy of the measurement.
3. The long-range models may have an extension range of 10mm, which is suitable for a wider range of inner diameter
measurement requirements.
III. The Impact of Expansion and Contraction on Measurement Accuracy
The magnitude of expansion and contraction directly affects the accuracy and stability of the measurement:
1. A smaller expansion or contraction amount usually indicates higher measurement accuracy.
For instance, an internal diameter micrometer with an expansion or contraction of 5mm might have
a resolution of 0.001mm.
2. A larger extension range provides a wider measurement range, but it may sacrifice a little in precision.
The model with an 8mm extension range may have a resolution of 0.005mm.
3. The greater the expansion and contraction amount, the rigidity of the measuring rod may slightly decrease.
This might have a negligible impact in scenarios with extremely high precision requirements.
IV. Select an inner diameter micrometer with an appropriate extension range
Selecting an inner diameter micrometer with an appropriate extension range is crucial for precise measurement:
1. For measurements of small holes (such as those with a diameter of 5-10mm), it is recommended to choose
the high-precision model with a 5mm extension range.
2. For medium-sized holes (with diameters ranging from 10 to 50 mm), models with an extension range
of 6 mm or 8 mm are usually sufficient.
3. For the measurement of large-diameter holes, models with an extension range of 10mm can be considered to
accommodate larger dimensional variations.
V. Techniques for Ensuring Precise Measurement
Even if a suitable internal diameter micrometer is selected, the correct usage method is the key
to ensuring precise measurement:
1. Before measurement, perform zero-point calibration to ensure the accuracy of the measurement benchmark.
2. During the measurement process, ensure that the measuring rod is perpendicular to the axis of the measured hole
to avoid errors caused by inclination.
3. Gently shake the internal micrometer and locate the position with the smallest reading.
This is usually the most accurate measurement point.
4. Regularly calibrate and maintain the internal diameter micrometer to ensure the accuracy
and stability during long-term use.
