What are Grinding Wheels? Basics about Grinding Wheels Uses & Applications
Tight tolerance and a high surface finish are always desirable in manufacturing, and a grinding wheel is just the right tool to achieve both. But what are grinding wheels? How does it work, and what are the different types of grinding discs? This article will provide a detailed guide on grinding wheels, right from their construction to their intended use.
What are Grinding Wheels? Usage and Application
Grinding wheels are abrasive tools that are used to remove a fine layer of material from the surface of the workpiece. This is done to achieve the desired dimensional tolerance and surface finish.
Using a Grinding Wheel
At high speed, rotate the grinding wheel so it comes into contact with the workpiece and removes the material. This high-speed contact can generate high frictional heat (especially when grinding tough metals like stainless steel). This makes it important to use cutting fluid to prevent overheating of the tool and the workpiece.
When using a grinding wheel, always maintain to-and-fro movement between the grinding wheel and the surface of the workpiece. This is required to ensure a smooth and uniform surface finish. Furthermore, when a high volume of material is to be removed, it is advised to gradually grind the workpiece in multiple passes. This is because grinding at the same spot for a prolonged time can result in overheating. Thus damaging the workpiece and the tool.
Applications of Abrasive Wheels
Common usage of grinding wheels is to grind the workpiece and achieve the desired dimensional accuracy or improve its surface finish. Therefore, it is an important operation that is performed on almost every workpiece before finalizing the machining process.
Common use of grinding is to remove unwanted material or smoothen sharp edges in metalworking industries, and to finish and achieve a smooth surface on jewelry and other intricate works.
Types of Grinding Wheels
Grinding wheels can be classified based on the abrasive and bond type.
Generally, resinoid and rubber are the most commonly used bond types and are used for most general-purpose applications. The vitrified bond provides the strongest adhesion, preventing the abrasive particles from falling off during intense grinding applications.
Similarly, the harder the abrasive, the better the material removal ability of the grinding wheel. Based on the abrasive material, there are four types of grinding wheels:
Aluminium Oxide Abrasives
Aluminium oxide is the most commonly used abrasive on grinding wheels and is best suited for grinding ferrous metals and steel workpieces. These abrasive wheels are colour-coded as grey, white, pink, brown, etc.
Grey and brown are the most widely used wheels for general-purpose grinding applications, as they provide good durability at a low cost. These wheels are ideal for machining low-carbon steel.
Pink and white grinding discs are comparatively harder and are used for grinding tougher grades of steel (such as stainless steel) that generate high frictional heat during the grinding operation.
Apart from these, aluminium oxide grinding wheels are also available in ruby red colour. These wheels are extremely tough and are used for machining tool steel.
Silicon Carbide Abrasives
Silicon carbide abrasives are ideal for grinding non-ferrous metals like aluminium, copper, etc., and non-metals like marble, granite, etc.
These grinding wheels are available in black and green, with green wheels having better sharpness than black wheels. Silicon carbide wheels are also used for grinding stainless steel when a high-quality surface finish is required.
Ceramic Abrasives
Ceramic abrasives are relatively new and are not readily available on the market. These abrasives tend to self-sharpen by breaking the dull grains, attaining a renewed sharp cutting edge.
These types of grinding wheels are ideal for applications where extensive material removal is required while maintaining a long tool life. However, ceramic grinding wheels are comparatively expensive and cost around three times more than aluminium oxide abrasive wheels.
Diamond Abrasives
Diamond abrasives are ideal for grinding extremely tough materials like concrete, asphalt, stones, etc. These grinding discs can be used on almost any material, but their high-cost limits them from being used for general-purpose applications.
Specification of Grinding Wheels
Each grinding wheel has a specific code to identify its specifications. This code provides information about the five basic elements: Abrasive type, grain size, grade, structure, and bond type.
Let us consider an example of a grinding wheel marked as A24S7B. Here, the code can be divided into 5 elements, such as A-24-S-7-B, where each element provides information about the type of abrasive, grain size, grade, structure, and bond type, respectively.
The tables below provide details about the commonly used codes for the specification of grinding wheels:
Different types of abrasives provide different types of material removal capabilities. Similarly, the type of bond determines the ability of the grinding wheel to retain the abrasive particles under the action of the cutting force.
Apart from that, the grain size determines the material removal rate and the surface finish of the final product. The higher the grain size, the lower the material removal rate and the smoother the surface finish.
Buy Grinding Wheels at L&T-SuFin
The type of grinding wheel to be used is based on your application requirements and the type of machine you use. Therefore, when buying a grinding wheel, it is important to consider the abrasive type, bond, bore diameter, size, and thickness of the wheel.
L&T-SuFin provides a wide range of grinding wheels to choose from. They deliver the product all over India. Moreover, you can request a quote based on your order quantity.
5 Tips for Choosing The Right Grinding Wheel For Your Project
Almost every machining operation is followed by the grinding of the workpiece to achieve the required dimensional accuracy or to smoothen its surface. However, each application demands a different type of grinding wheel. This helps achieve the right amount of material removal with the desired surface finish and tool life.
This article will guide you to choose the right grinding wheel for your application based on the type of material, abrasive, bond type, grit size, and grade of the grinding wheel.
How to Choose the Right Grinding Wheel for Your Project?
The selection of the right grinding wheel is based on various factors, and it is important to consider each factor based on your application.
Type of Material Being Ground
| Type of Material | Best Suited Abrasive |
| Ferrous Metals | Aluminum Oxide |
| Non-ferrous Metals | Silicon Carbide |
| Titanium, Tool steel, etc. | Ceramic |
| Concrete, Asphalt, Stone, etc. | Diamond |
Every material responds differently to the grinding operation. While some materials are easy to grind, others pose several challenges during the operation. As a result, it is important to select the right grinding wheel for your project.
Ferrous materials generally use aluminium oxide grinding wheels. On the other hand, silicon carbide wheels are ideal for non-ferrous metals like copper, and some non-metals.
Tough materials that are difficult to grind with standard abrasives usually require the use of ceramic wheels. Diamond abrasives are best for grinding non-metals like concrete, asphalt, and stones.
Amount of Material to be Removed by the Grinding Wheels.
The grain size of the abrasive primarily determines the amount of material removed during a grinding operation. The coarser the grain, the higher the material removal rate.
However, a high material removal rate leads to a poor surface finish. As a result, a fine-grain abrasive is recommended for finishing operations where a small amount of material is removed to achieve a high surface finish.
Every grinding operation involves using a coarse-grain abrasive to remove material and achieve an even surface. Achieving the required surface finish usually requires a fine-grain abrasive grinding.
Removing a large amount of material requires high grinding pressure. This grinding pressure can dull the abrasives. It can also generate frictional heat. As a result, it is advised to use a soft bond grinding wheel. This allows the dull grains to fall off, preventing the rubbing action and reducing frictional heat.
Therefore, a soft bond grinding wheel with coarse abrasives is recommended for grinding hard materials. A hard-grade wheel is preferred for grinding soft materials.
The Surface Finish Required
The surface finish of the final product depends on the grit number of the grinding wheel. Every grinding wheel has a grit number. This provides information about the density of abrasives on the wheel.
A fine-grit abrasive is suitable for operations where a good surface finish is desirable over a high material removal rate. Furthermore, fine-grit wheels are also recommended for applications where the area of contact between the grinding wheel and the workpiece is very small.
This is because a small area of contact exerts greater force per unit area. It can rip the abrasives off the wheel. A densely packed fine grit abrasive provides comparatively more points of contact to distribute the load. It prevents the abrasives from falling off.
Speed of The Grinding Wheel
The speed of the grinding wheel determines the type of bond suitable for your application. The higher the wheel speed, the higher the cutting force. Therefore, preventing the abrasives from falling off requires a durable bond.
Generally, the vitrified bond is suitable when the wheel speed is below 6,500 SFM (surface feet per minute). Organic bonds are recommended for up to 8,500 SFM. For speeds over 8,500 SFM, use special bonds rated for high-speed grinding.
Apart from the type of bond, wheel speed also affects the grade hardness of the wheel. By the rule of thumb, a grinding wheel acts one grade harder or softer for every 1,000 SFM increase or decrease in the wheel speed, respectively.
Coolant Requirement
Different types of bonds act differently based on the use of coolant during the grinding operation. During dry grinding, vitrified bond wheels will be harder and generate more heat. This can result in overheating of the workpiece. On the other hand, Organic bond wheels tend to soften under heat. This increases tool wear.
In contrast, using a coolant during the grinding operation will reduce the frictional heat. The absence of frictional heat will soften the vitrified bond wheels and harden the organic bond wheels.
Grinding Wheel Maintenance
Grinding wheels are multipurpose tools that are used for various applications. Apart from selecting the right grinding wheel, it is also important to ensure proper maintenance of the wheel.
Grinding produces tiny chips that can fill the pores on the wheel, rendering the wheel dull. Therefore, it is important to dress the wheel regularly to retain its sharpness. The maintenance of the grinding wheels involves running the wheel and placing a dresser tool against its face.
The dresser tool removes the top layer of the grinding wheel, which removes the impurities and re-sharpens the grinding wheel.
Buy the right Grinding Wheel From L&T SuFin
With these tips in mind, you will be better prepared to choose the right grinding wheel for your project. You can make a more informed decision on which one to buy. L&T-SuFin is an excellent marketplace platform to buy grinding wheels. It provides detailed information about each grinding wheel, which makes it easy to select the right one for your application.
Guide to Surface Grinding Wheels in India
A Surface grinding is one of the most used grinding operations. Each material requires a specific type of grinding wheel. But what are the different types of surface Grinding Wheels available in India, and how much do they cost?
This article offers a comprehensive guide to surface Grinding Wheels in India. It provides info on the types and costs of Grinding Wheels available in India.
What is a Surface Grinding Wheel?
Surface grinding is a machining process. It uses a rotating abrasive wheel to remove a fine layer of material from the workpiece's surface. It produces a smooth surface free from any imperfections or impurities.
It is a precision machining operation. It helps to get the desired accuracy and surface finish in the final product. Almost every manufacturing industry in India widely implements it. Surface grinding is suitable for almost every material. But you must select the right Grinding Wheel for the right use.
Types of Surface Grinding Wheels Available in India
Different types of surface Grinding Wheels are available in the Indian market, and selecting the right grinding wheel for your use will help you achieve the desired result.
Aluminium Oxide Grinding Wheels
The Indian industry most commonly uses Aluminium oxide Grinding Wheels. These Grinding Wheels are suitable for machining various ferrous metals. It is a general-purpose grinding wheel that provides good grinding capability at a low cost.
Aluminium oxide Grinding Wheels commonly find their use in India's iron and steel industry. Apart from that, Surface Grinding Wheels are widely used in metalworking.
Silicon Carbide Grinding Wheels
The grinding of non-ferrous metals generally uses Silicon carbide wheels. Construction industry also uses it for grinding marble and granite workpieces.
If you are looking for a surface Grinding Wheel to grind or polish jewellery, a silicon carbide wheel is the way to go.
Special Abrasive Grinding Wheels
Special abrasives include ceramic Grinding Wheels and diamond abrasive Grinding Wheels. Ceramic Grinding Wheels have sharp abrasives that can grind almost any material. However, these wheels are comparatively expensive. They are used only when a high material removal rate is needed with a long tool life.
But, diamond abrasive wheels are used for surface-grinding tough materials. Both Grinding Wheels are costly and should only be used when needed.
Things to Look for When Buying a Grinding Wheel
Select the right abrasive type for your project.
Select the right size of the grinding wheel.
Ensure that the grinding wheel you buy fits your surface grinding machine.
Select the right thickness of the grinding wheel.
A thick wheel is suitable for grinding large workpieces, while a thin Grinding Wheel can reach intricate patterns on the workpiece.
Consider the bore diameter of the wheel.
Generally, the right bore diameter depends on the size of the shaft of your surface grinding machine.
Consider the bond type for the grinding wheel.
Generally, a resinoid bond is used for most uses but a vitrified bond is preferred for grinding tough materials, where high cutting forces are involved.
Finally, you should also consider the maker of the Grinding Wheel.
Although it does not sound important, a good brand ensures a high-quality Grinding Wheel that can last longer and provide an excellent surface finish. Brands such as Makita, Norton, and Bosh are preferable for industrial use, as they provide quality products.
Choose the right Grinding Wheel at L&T-SuFin
Selecting the right surface Grinding Wheel is crucial in achieving the desired grinding results while ensuring the minimum cost of the operation. However, it requires adequate knowledge about the use of each wheel and the best manufacturers available in India. You can check out L&T-SuFin website to purchase surface Grinding Wheels from leading manufacturers in India, such as Norton, Makita, Bosch, Stanley, etc. Let us know how you found this article on comprehensive guide to surface Grinding Wheels.
HS Codes for Grinding Wheels: Everything you Need to Know
Grinding wheels are available in different types, suitable for different applications, and each type has a specific HS code. There are thousands of HS codes for grinding wheels, and identifying the right one for your product can be challenging, especially if you are new to the trade. This article explains what HS codes are and talks about the different HS codes associated with grinding wheels.
What are HS Codes for Grinding Wheels?
HS Codes, also known as Harmonized System Codes, are internationally accepted codes that are used to uniquely identify a product in international trade. These codes are governed by the World Customs Organisation (WCO), and each code consists of six digits that provide a detailed description of the product.
The first two digits of the code are known as the "chapter" and provide details about the category of the product. The next two digits are known as the "heading" and provide details about the type of product. Finally, the last two digits, known as the "sub-heading," provide details about the specification of the product. For example, Chapter 68 of the HS code deals with articles of stone, plaster, cement, asbestos, mica, or similar materials. In this chapter, Heading 6804 deals with different types of grinding wheels, under which Sub-heading 6804.23 is specifically concerned with natural stone grinding wheels.
Similarly, there are different HS codes for different types of grinding wheels available on the market.
Classification of Grinding Wheels and their HS Codes
Grinding wheels primarily fall under Heading 04 of Chapter 68 from Section XIII, which deals with articles of stone, plaster, cement, asbestos, MICA or similar materials.
There are various types of grinding wheels, and each type has its own HS code.
| HS Code | Type of Grinding Wheel |
| 6804.10 | Millstones and grindstones for milling, grinding or pulping |
| 6804.21 | Synthetic or natural diamond Grinding Wheels |
| 6804.22 | Grinding wheels consisting of ceramic or other agglomerated abrasives. |
| 6804.23 | Natural stone Grinding Wheels |
| 6804.30 | Hand-held grinding or polishing stones |
| 8205.90 | Pedal-operated grinding wheels or grinding wheels with a hand frame |
Synthetic or Natural Diamond Grinding Wheels
Synthetic or natural diamond grinding wheels consist of diamonds as abrasive particles. These grinding wheels are extremely durable and are generally used for grinding tough materials like carbide, titanium, etc.
Apart from the abrasive material, grinding wheels are also classified by the type of bond used. While a soft bond allows the abrasive particles to fall off under strong cutting forces, a hard bond prevents the falling of the abrasive particle, thereby enhancing the tool's life.
Generally, a hard bond, such as a Vitrified bond, is used with diamond grinding wheels, as it provides the required bonding strength to completely utilize the diamond abrasive by preventing it from falling off prematurely.
Synthetic and natural diamond abrasives collectively fall under the 6804.21 HS code. However, certain countries like India, use additional digits to further classify them. For example, HS code 6804.2110 is designated for synthetic diamond grinding wheels, while 6804.2120 is designated for natural diamond grinding wheels.Ceramic or other Agglomerated Abrasives
Ceramic grinding wheels consist of ceramic aluminium oxide abrasives that provide them with excellent sharpness and good durability. These are stronger than conventional grinding wheels and are used for applications where high material removal rate is preferable.
The abrasive particles in these wheels have multiple fracture points. Once the abrasive loses its sharpness, it automatically breaks along the fracture point, resulting in the self-sharpening of the tool.
As a result, these grinding wheels do not require frequent replacement and are ideal for heavy-duty grinding operations, which would otherwise render the abrasives blunt, shortening the tool's life.
Generally, ceramic and other agglomerated grinding wheels fall under the 6804.22 HS code of section XIII.Natural Stone Grinding Wheels
Natural stone grinding wheels are generally used for grinding and shaping natural stones such as granite and marble. The abrasives used on these wheels are comparatively less durable, and are, therefore, not suitable for grinding hard metals.
6804.23 is the HS code assigned to natural stone grinding wheels.Hand Sharpening or Polishing Stones
Hand sharpening or polishing stones are hand-held abrasive tools that are used to grind or polish small workpieces. They work similarly to a grinding wheel but are generally available in bar form, which is easier to hold while applying the required grinding force on the workpiece.
Hand sharpening or polishing stones fall under the 6804.30 HS code.Grinding wheels with Frame or Pedal
These grinding wheels are operated manually and generally have a hand lever or a foot pedal mechanism to rotate the tool. These tools are ideal for small-scale grinding applications of soft materials like aluminium.
Generally, 8205.90 is the HS code used for the grinding wheels under this category.How to find and search the HS code for grinding wheels?
During the customs procedure, you will have to fill in the appropriate HS code for the type of grinding wheel you are importing or exporting. Failing to do so can be considered misleading and non-compliance, making you liable for the associated penalty as per the law.
Therefore, it is important to identify the right HS code for your product. You can find the right HS code for a grinding wheel based on the type of grinding wheel. Generally, every country has its commerce and industry portal that allows you to search for a product by its name to get the corresponding HS code or vice-versa.
Find HS Codes For Grinding Wheels at L&T-SuFin
HS codes are generally used by distributors and manufacturers during the import and export of grinding wheels. These codes can also be used to identify the country of origin and the manufacturer associated with the product. However, if you want to avoid the hassle of dealing with HS codes and customs procedures, you can check out L&T-SuFin to directly purchase the required grinding wheels in bulk for your small-scale or large-scale applications.