Types of Gauges in Metrology

Metrology is an important department of Mechanical engineering that deals with the measurements of a workpiece. Metrology is every time called the science of measurements that depends upon two important factors. The factors are time and quantity that has to be measured by an engineer in order to ensure the precision of a workpiece.

Every material has some degree of error in it which can impact negatively the mechanical efficiency of a machine's components. Therefore, for removed those errors from a workpiece some measuring tools are dreamed up by engineers such as surface texture measuring devices, tolerance measuring devices, screws threads measuring devices, and so on.

Gauge is the tool used by engineers to rectify errors in terms of linear measurements. Linear measurements deal with measuring lengths, diameters, heights, etc. It is also used by engineers to secure differences in a workpiece. In this assessment, Gauges and their kinds are critically analyzed briefly in all possible ways. Everyone is seeking suitable knowledge about Gauges due to the conciseness of the description.

Definition of Gauge:

A gauge is an inspection tool that is used by engineers to measure the tolerance limit of a component. Gauges are mainly utilized by engineers in order to segregate the appropriate dimension of a workpiece.

Some fundamental limitations are present within that a Gauge should be made by manufacturing.

Therefore, if the Gauge appeared accurate in relation to the ideal Gauge then the workpiece should be measured with that Gauge.

The operator can use a Gauge without having vested knowledge in operating those mechanical instruments. Also, Gauges consume less time compared to other measuring devices.

Types of Gauges in Metrology:

Plain Gauge is defined as the dimension measuring or inspection tools, without a scale to measure any manufacturing part of tools.

In order to check shafts and the holes, Plain Gauge is used.

Plain Gauge is classified into four [04] different types. Those types are in follows:

Depending on the manufacturing principles and types

·                 Standard Gauge

·                 Indicating Gauge

·                 Limit Gauge

·                 Combination Gauge

Depending on the purpose

·                 Workshop Gauge

·                 Inspection Gauges

·                 Master Gauge (Reference Gauge)

Depending on the function

·                 Dimension Measuring Gauge

·                Inside Dimension Measuring Gauge

§   Plug Gauge

§   Pin Gauge

·                Outside Dimension Measuring Gauge

§   Snap Gauges

§   Ring Gauges

·                Both sides Dimension Measuring Gauge

§   Caliper Gauges

§   Geometric Measuring Gauge

§   Gauges for concentricity

§   Gauges of Taper

§   Gauges of Profile

Depending on the Design

·                 Single limit and Double limit

·                 Single-ended and Double-ended

·                 Fixed and Fastened

·                 Geometry Measuring Gauges

Depending on the Manufacturing Principles and Types:

1. Standard Gauge:

Standard Gauges are defined as measuring tools that checked the copy of the mating parts of the material. This gauge cannot be used by an engineer due to the existence of tolerance in a component.

2. Limit Gauge:

Limit Gauges are defined as the gauges that are used to measure a component by two limits, one is high and low. So, there are two gauges for measuring the dimensions of the material. Two gauges are the Go-Gauge and the Not-Go-Gauge.

The part of the component has to pass through the Go-Gauge and for the Not-Go-Gauge, it has not to pass. This gauge is widely used in industries.    

3. Indicating Gauge:

Indicating Gauges are defined as the gauges which are used to measure a part of the material and showed the measurements on the display. These gauges displayed the measurements on the indicator or display, so it is termed the Indicating Gauges.

This gauge is more complex than other gauges. The best example of the indicating Gauge is Dial Gauge. Nowadays such indicating gauges have a system of visual display.     

4. Combination Gauge:

Combination Gauges are defined as gauges that can take more than one dimension of the parts of the material consecutively. It is very useful as at a time more than one measure of the parts can be taken. It consumes less time and produced more efficient results.

Depending on the Purpose:

Workshop Gauge:

A workshop Gauge can be defined as the gauge which is used to measure the parts of the material at the time of production. This gauge is used in the production time at the workshop so this gauge is named the Workshop Gauge.

The Workshop gauge is designed like that, where the tolerance is in the centerline. So the Workshop Gauge is most competent in the plants or workshops slightly than the others.

Inspection Gauge:

Inspection Gauge can be defined as the gauge which is used by the inspections in the plants after finishing the manufacture of the products to accept it. As the acceptance or the rejection is depending on the gauge measurements so the tolerance of this inspection Gauge is rather more than the Workshop Gauge.

If the tolerance of the material parts is high then it is accepted otherwise this material should be rejected.

Master Gauge (Reference Gauge):

Master Gauge can be defined as the gauge to check the other gauges. As the expenditure is involved, the measuring components, optimizers, slip gauges, etc. are checked by the master gauge or reference gauge.

All the other gauges are checked by this gauge so which this gauge is called the Master Gauge. It is very useful because the efficiency of the other gauges depends on the master gauge.

If the master gauge cannot check the other gauges or components properly then those gauges and components cannot give accurate results.

Depending on the function

Dimension Measuring Gauge:

Dimension Measuring Gauge can be defined as a gauge that measures very small parameters of the parts of the materials with very high accuracy. These dimensions are height, depth, diameter, etc., and are measured by the Dimension Measuring Gauge.

This Gauge is used to get very specific and accurate dimensions. This Dimension Measuring Gauge is classified into three types. These are as follows:

Inside Dimension Measuring Gauge:

Inside Dimension Measuring Gauge is used to measure the inner or inside diameter, width, height, etc. For example, the inner diameter of a bolt is measured by Plug Gauge.

Inside Dimension Measuring Gauge is classified into different types. These are as follows:

·                 Plug Gauge

·                 Pin Gauge

Plug Gauge

Plug Gauge is a cylindrical shaped {Go and Not-Go} type Gauge. It is used to measure the diameter of a hole-like thing with accuracy. In order to measure the parts, one has to pass Measurements and the other one has not to pass the Measurements. That is called {the Go and Not-Go} measurement.  

Pin Gauge:

Pin Gauge generally worked on the same working principles as the Plug Gauge, which is used to measure a diameter that is more than 75mm. Measurements of the width of the slots or grooves are done by Pin Gauge. It is measured across the cylinder bore and the gauge is placed as lengthwise.   

Outside Dimension Measuring Gauge:

Dimension Measuring Gauge can be used to measure the outer or outside diameter, width, height, etc. As an example, the outer diameter of a bolt can be measured by Snap Gauge.

Dimension Measuring Gauge is classified into different types. These are as follows:

·                 Snap Gauge

·                 Ring Gauge

Snap gauges

The Snap Gauge is the gauge which is U-shaped {Go and Not-Go} type gauge. It has jaws by which it checks the accuracy and tolerance. In order to measure the parts, it has to pass Measurements and another one has not to pass the Measurements. That is called {Go and Not-Go} measurements. Here Go is the maximum limit and the Not-Go is the minimum limit.  

Ring Gauge:

The Ring Gauge is the same as the snap gauge but it is separate from the Go and Not-Go pass or in a single ring.    

Both Sides Dimension Measuring Gauge:

Both Sides Dimension Measure Gauge is used to measure the outer or outside and inner or the inside, both diameters, height, width, etc. For example, the outer and inner diameters of a bolt can be measured by Calipers.

Outside Dimension Measuring Gauge is classified into different types. And those are

·                 Caliper Gauge

·                 Geometric Measuring Gauge

·                 Gauges for concentricity

·                 Gauge of Taper

·                 Gauge of Profile

Caliper Gauge:

The Caliper Gauge is the gauge that is used to measure the distance of any object, between two different sides. It is very useful as it can give more accuracy and is very easy to use. Such examples are the Vernier caliper, Digital Caliper, Dial caliper, Micrometer caliper, etc.

Vernier caliper gauge image

Geometric Measuring Gauge:

A geometric measuring gauge can be defined as a measuring device that can measure its concentricity, taper, and profile. Mainly the geometric measuring gauge is used to measure the roughness or unevenness of the surface. There are several types of measuring and calculating methods for roughness characterization through the concentric, profile, and so on.

Gauges for Concentricity:

The concentricity gauge can be used to measure runout by revolving the cylinder or the loaded round on two pairs of bearings these are captured in anodized aluminum blocks. This gauge mainly measures the circle of the plane.

Gauges for taper:

The taper gauge is basically used to measure the internal tapers. This gauge looks like an internal gauge in the shape of a frustum of a cone.

Gauges for Profile:

The profile gauge or contour gauge is a tool that is used to draw the profile onto another surface.

Depending on the Design

Single limit and Double limit:

The single-limit gauge has a jaw that is fixed to make the gauge limit, but in the case of the double-limit gauge, it has an adjustable jaw that can be doubled with the help of the adoptable jaws.

Single-ended and Double-ended:

The single-end gauge has a single end that could be either the Go end or the No-Go end. But in Double-end gauge has both ends, one end is {Go end other one is No-go end}.

Fixed and Fastened Gauges:

In the fixed end gauge both jaws are fixed at the same time, but in Fastened end gauge only one jaw can move or moveable. These types are the main types of snap gauges.

Ending Thoughts of Gauges:

Concerning the above description of Gauges and their types, it can be maintained that the field of metrology is incomplete without Gauges. The precision of machine parts is one of the most important factors that decide the mechanical advantage and well as the efficiency of the machine parts.

Due to this reason, proper knowledge about Gauges should be collected by engineers before making machine parts. Working in a lathe, grinding, milling or other metal forming processes cannot be made within the tolerance limit and without measuring their errors.

In regards to this, Gauges play a vital role. The above description is very brief, that just occupies the kinds and their descriptions. Hence, some gaps exist in this assessment. Although, if an engineer wants to seek knowledge on Gauges this assessment can be a productive one.