Title: Inspection Tools
Course: PW-Course-Import-Test > Section: Module 3: Acceptance Criteria

Module 3

Depending on the size of the company, complexity of the parts and accuracy of inspections required, a company will have a wide array of tools available to perform inspections. Sometimes there are also multiples of the same tool available. In this section we will discuss some of the commonly used inspection tools and their uses.

Digital Calipers

The Digital Caliper is a precision instrument that can be used to measure internal and external distances extremely accurately. The example shown below is a digital caliper as the distances/measurements, are read from a LCD display.

Digital Micrometer

A digital micrometer is a gauge that measures small distances or thicknesses between its two faces, one of which can be moved away from or toward the other by turning a screw with a fine thread. The distance is displayed on a LCD display.

Tappi Chart

Tappi chart is a custom transparency used to measure the size of spots, defects, or inclusions over the range of 0.02 to 5.00 square millimeters. Parts sent by suppliers sometimes can have particulate matter that is on the surface of the part or embedded within the part. Many companies have cleanliness standards for their parts and some of this particulate matter may be unacceptable if they are above a particular size.

A tappi chart helps a quality inspector to estimate the size (area) of the particulate and determine if it falls within the acceptable range.

Pin Gage

Pin gages are available as a set of various size increments and are used to check the tolerance of a hole in the product. Use of these gages to measure internal diameters of products eliminates the requirement of complex measuring equipment and setup time. Pin gages should be used in a GO-NOGO combination. The purpose of the GO gage is to determine whether the hole has met the low limit of the specifications. If a hole is too small the GO gage will not enter. The larger NOGO gage checks the upper limit of the hole. If the hole is too large the NOGO gage will enter. When the GO gage enters and the NOGO gage is unable to enter the design specifications of the hole have been met.

Tensile Tester

A tensile test, also known as tension test, is probably the most fundamental type of mechanical test you can perform on material. Tensile tests are simple, relatively inexpensive, and fully standardized. By pulling on something, you will very quickly determine how the material will react to forces being applied in tension. As the material is being pulled, you will find its strength along with how much it will elongate.