Calipers are a commonly used precision measuring tool that can measure the inner and outer diameters, depths,
and thicknesses of objects. This article will provide a detailed explanation of the part names for measuring the inner
diameter with calipers and offer a comprehensive analysis of the structure and functional zones of calipers.
I. What is the part of a caliper used for measuring the inner diameter called?
1. The part of a caliper used for measuring the inner diameter is called the inner measuring jaw. The inner measuring
jaw is usually located at the top of the caliper and is smaller in shape, making it convenient to insert into holes
or slots for measurement.
2. The design of the internal measuring jaws is to precisely fit onto the inner wall of the object being measured,
thereby measuring its inner diameter. When in use, gently insert the internal measuring jaws into the hole to be
measured, and then slowly open them until both ends of the internal measuring jaws are in close contact
with the hole wall.
3. It should be noted that when measuring the inner diameter with the inner measuring jaws, excessive force should
be avoided to prevent damage to the caliper or the object being measured.
II. Structure and Functional Zones of the Caliper
1. The caliper is mainly composed of the following parts: main scale, vernier, outer measuring jaws,
inner measuring jaws, depth gauge, tightening screws, etc.
2. The main ruler is the reference ruler of the caliper, marked with millimeter or inch scales. The vernier is a sliding
ruler that works in conjunction with the main ruler to enhance measurement accuracy. The outer measuring
jaws are used to measure the outer diameter and length of an object. The inner measuring jaws are used to measure
the inner diameter of an object. The depth ruler is used to measure the depth of an object. The tightening screw
is used to fix the position of the vernier.
3. Different types of calipers may have slightly different structures and functional divisions. For instance, electronic
calipers have a digital display, allowing for a more intuitive reading of the measurement results; while vernier calipers
require the combination of the vernier and the main scale's markings to read the measurement results.
III. How to Use Calipers Correctly for Measuring Inner Diameter?
1. When using calipers to measure the inner diameter, first select the appropriate type and range of calipers.
Ensure that the range of the calipers can cover the inner diameter range of the object being measured.
2. Gently insert the internal measuring jaws into the measurement hole, then slowly open them until the two ends of
the jaws are in close contact with the inner wall of the hole. Avoid applying excessive force to prevent damage
to the caliper or the object being measured.
3. By reading the scale values of the main ruler and the cursor, the inner diameter size of the measured object
can be obtained. During the reading process, it is necessary to ensure that the line of sight is perpendicular
to the scale line to avoid reading errors.
IV. Maintenance and Care of Calipers
1. After use, the caliper should be wiped clean and coated with anti-rust oil to prevent rusting. When storing,
the caliper should be placed in a dry and ventilated area, avoiding direct sunlight and humid conditions.
2. Regularly inspect all components of the caliper to ensure they are in good condition. If any damage or decrease
in accuracy is detected in the caliper, it should be promptly repaired or replaced.
3. Avoid dropping or colliding the caliper to prevent any damage to its accuracy.
