An inside caliper is a measuring instrument which is used to gauge internal dimensions, such as the internal diameter of a pipe. These calipers are sold in most locations which sell calipers and other measuring devices, and they can also be ordered directly through manufacturers. Several companies make specialty calipers which are designed for specific applications, including devices which can be used with microscopes, in operating rooms, and in other settings which may have special requirements.
The design of a pair of inside calipers consists of a pair of curved arms, with the curves facing outwards. To take measurements, the device is inserted into the object being measured and the arms are adjusted until their tips touch either side of the opening. Then, the inside caliper can be read. Some have adjusting and locking screws which allow people to remove the caliper from the object being measured after the measurement is taken so that the caliper can be more easily read.
These devices are often used by machinists, who need to be able to take very precise measurements and who work within limited tolerances. Small variances in machining and design can translate into large problems on everything from precision scientific instruments to sports cars. The inside calipers may have design features such as padded arms which are designed to prevent scratches, as well as nonreactive metal materials so that they can used in corrosive environments.
When selecting an inside caliper, it is important to choose the right tool for the job. People should think about which system of measurement they wish to use, as it is easier to purchase a tool which gives measurements in the right units than it is to convert constantly. It is important to think about potential sizes of objects being measured, as the device cannot measure if it will not fit, and to consider factors such as whether the environment will be wet or contain corrosive chemicals.
Like other instruments used for measuring, an inside caliper needs to be properly maintained in order to work accurately and effectively. The arms cannot be bent, or the measurements will be skewed. It is a good idea to keep the device in a protective case when it is not in use, and to handle the device carefully while taking measurements to avoid forcing it, as this may cause damage to the inside caliper or the device being measured.