The tooling and machining industry uses a wide range of processes to manufacture components. These components are applicable in various industries and are manufactured using versatile materials.

Internal grinding is also a type of machining process in which the internal diameter of a cylindrical component is machined and finished.

If you want to learn about the pros, cons, and applications of this process, read below.

What is Internal Grinding?

The internal grinding process involves a grinding wheel, which helps to grind the inner part of the components. The rotation of the wheel suits the finishing and shaping of the component from the inside.

How Internal Grinding Works?

I.D. grinding is a process that works in different steps, and these are as follows:

• The first stage is the stage of setup in which the workpiece is set on the machine, either mounted on the chuck or fixed between the centers. The grinding wheel, which grinds the inner part, is fixed on a spindle.
• The grinding wheel is then inserted in the internal part of the workpiece, and the spindle moves at a high speed.
• The grinding process starts with the wheel and workpiece. As the wheel rotates, it removes material from the inner part of the components.
• During the grinding process, coolant is also applied to ensure that the workpiece doesn't get damaged.
• The machine controls the speed, depth, and feed rate for the cutting process, ensuring tight tolerance.
• Once the desired dimensions and finishing is attained, the component is inspected thoroughly for precision.

Advantages of Internal Grinding

The process of internal grinding is opted for by different industries due to the benefits it offers; some of these benefits are as follows:

High Precision

The internal grinding process helps achieve tight tolerance, and components that require such tolerance can easily be manufactured using it.

It helps to achieve precise and consistent dimensions for components like bearings and bushings.

Enhanced Surface Finish

The process of internal grinding is also a finishing process and leaves behind a refined and smooth surface for the components.

It is therefore opted for pistons and hydraulic cylinders as smooth finishing ensures wear resistance.

Versatility

Internal grinding is carried out on various materials, which are composed of metals as well as non-metals.

Also, the process is suitable for all sizes of cylindrical and conical shapes, which can cater to different application requirements.

Enhances Component Performance

I.D grinding helps to ground the internal surfaces so that the components offer better fitting with one another and an improved span of life.

Also, due to a finished internal surface, the friction is reduced on the moving parts.

Compatible with Complex Components

Internal grinding is compatible with components that have complex shapes. It can offer detailed features, slots and even contours on the inner part of the component.

Disadvantages of Internal Grinding

Internal grinding is a very versatile process, yet it does have some downsides, and these are as follows:

High Initial Investment

Internal grinding requires special machinery, which is expensive. When opted for small scale production, it doesn't prove to be worth it.

Moreover, the machine can be operated by skillful laborers and that also adds to the cost.

Slow Rate of Removal

The rate of removal using the internal grinding process is very low. Hence, when a large amount of material needs removal, the process turns out to be less efficient.

Size Limitation

The grinding process can grind limited sizes of components. It can not grind very small and very large components due to the lack of equipment and tooling capacity.

Wheel Maintenance

Grinding wheels do wear out over some time, so it is very important to maintain them.

In cases where the grinding wheels are not maintained, the quality and precision of the components may be disrupted.

Heat Generation

Grinding wheels generate a lot of heat.

It is very important to manage this heat with the help of coolants as it may damage the surface integrity especially when the materials of components are delicate.

Materials for Internal Grinding

Internal grinding is carried out over different components made using versatile materials, and these are as follows:

Hardened Steel

Hardened steel is composed of different types of steel, including alloy and tool steel. These materials are known for their strength and hardness.

Industries like automobiles and aerospace require components made using these materials. Hardened steel is subjected to heat treatment and then internal grinding to achieve components with tight tolerance.

Cast Iron

Cast iron is also very common; it is a material that is opted for by manufacturing companies through internal grinding.

It is equipped with resistance against wear and deformation and is used in machine components, hydraulic components, and engine blocks.

It is challenging to machine using other processes, but internal grinding offers relevant precision.

Carbide

Carbide is used for manufacturing cutting tools. It is very hard and can help with machining precision.

Internal grinding uses abrasive wheels and, hence, can handle the toughness of carbide when it comes to shaping it.

Internal Grinding Applications and Industries Served

The components manufactured using the process of internal grinding are used in various industries, and some of these components are as follows:

Bearings

Internal grinding helps produce bearings; the internal diameters of the bearings are precisely machined and create a very smooth finish.

It helps to reduce friction and also ensures rotation efficiency. Bearings are meant to meet precise tolerance and are used in applications like turbines, vehicle engines, and machinery.

Tools and Dies

Internal grinding helps in manufacturing dies, molds, and cutting tools that need high surface quality and tight tolerance.

The carbide tools pass through internal grinding so that the internal bore is finished appropriately, allowing precise component manufacture.

Industries like electronics, manufacturing, and tooling make use of these molds and dies.

Gears

Gears have precise internal bores, which are critical for smooth power transmission in the gearboxes. It helps finish the inner part of the gear hubs and ensures appropriate rotational performance.

These gears and gearboxes are used in aerospace, automobile, and other machinery applications after internal grinding.

Alternatives to Internal Grinding

Internal grinding has its significance, but there are other methods that can be opted as an alternative to this grinding process. These methods are as follows:

External Grinding

External grinding, also known as OD grinding, grinds the external surface of the cylindrical components. It focuses on the outer diameters and is used for different applications that need a smooth, finished outer surface.

The applications where it is mostly used are spindles, axles, and shafts. The process is also widely used in other components of automobile industries, like engine parts, as they need accurate dimensions.

Surface Grinding

Surface grinding also removes the material from the workpiece. However, it is mostly opted for finishing the surfaces that are flat.

Surface grinding also offers dimensional accuracy and precision. It is opted for components like plates, beds, and molds.

The industries that use surface grinding for its components are aerospace, automobile, and tool making.

Centerless Grinding

Centerless grinding is a process that grinds the external surface of the components without any fixture or chuck. The workpiece is fixed between the two wheels, and these wheels rotate to grind it.

The two wheels used in this process are the regulating wheel and the grinding wheel. It is mostly opted to manufacture cylindrical components in high volume.

Final Thoughts

Internal grinding is a popular manufacturing method. Apart from producing and shaping components, it also adds to the finishing process.

Hence, most of the components manufactured already have smooth surfaces, which eliminates the need for secondary finishing. The guide above is a complete insight into the process and its applications.

Choose DEK for Internal Grinding Services

If you are also looking for internal grinding services that offer high precision, smooth surface finishing, and affordability, contact DEK.

We have experienced team professionals followed by highly advanced automated equipment to serve you.

So, get in touch with us and specify your custom requirements for the internal grinding components.