Types of cylindrical grinding machines
A cylindrical grinding machine is a prominent member of the family of grinding machines in the metal-cutting industry. The working of this machine involves the use of a rotating grinding wheel that is fed into the metal workpiece from multiple directions to do away with any excess metal and thereby improve the shape and surface finish of the workpiece. This machine is quite commonly used in the machining and mechanical industries to improve the precision, shape, and surface finish of cylindrical objects like rods and columns made of metal including alloyed material and steel.
Cylindrical grinding machines are primarily categorized based on the types of workpieces or shapes they handle and their operating methods. With respect to the type of workpiece, surface, or shape, they handle, these grinding machines can be divided into the following four major types.
- Universal cylindrical grinder: Universal cylindrical grinders have the provision to grind both external and internal cylindrical faces with great accuracy and precision.
- Centreless grinder: Centreless grinders machines a workpiece without the use of a centering device. Also known as centerless cylindrical grinders, the machine allows free flow of material, thus improving production and through-put time.
- Internal cylindrical grinder: Internal cylindrical grinders are specifically designed to grind the inner diameters (ID) of cylindrical workpieces. It is usually carried out using a small grinding wheel that is mounted on a carrier or a spindle.
- Deglooving machine:Degloving machines, also known as stripper or slitter, are not cylindrical grinders in the true sense of the term. However, it is worthwhile to mention them here. Degloving machines are used to remove the unnecessary or excess layers of rubber in the form of grooves on cylindrical objects like tyres. This is done through the use of a knife or a grinding tool that makes grooves on a certain pattern onto the workpiece.
In addition to the above-mentioned types that are categorized based on the part of the cylinder that is ground or the process by which grinding takes place, cylindrical grinding machines can also be classified based on its operating method. Based on its method of operation, cylindrical grinders are further reduced to the following two categories.
- External cylindrical grinder: External cylindrical grinders are the most common cylindrical grinders found in the marketplace. It is specifically designed to grind the outer material of cylindrical workpieces.
- NC and CNC cylindrical grinder: Numerically controlled (NC) and computer numerically controlled (CNC) cylindrical grinding machines use numerical control technology to realize automation and high-precision control of the grinding process.
Specifications and maintenance of cylindrical grinding machines
Specifications of cylindrical grinding machines:
- Grind diameter: The diameter of the axis that can be ground is that the grinding machine has the ability to process workpieces of different sizes, which affects the applicable range of the equipment.
- Grinding length: The grinding length refers to the maximum length of the workpiece that can be ground, thus determining the processing capacity for the length of the workpiece.
- Grinding wheel size: The size and specification of the grinding wheel will affect the grinding efficiency, surface finish, etc. Different types of grinding wheels are suitable for varying materials and processing requirements.
- Machine weight: Machine weight: the weight of the machine; usually in tons. This figure affects the stability and vibration resistance of the machine during operation.
- Grinding precision: This refers to the cylindrical grinding machine's ability to achieve its accuracy, such as the roundness, cylindricity, dimensional accuracy, etc. Higher precision machines are more suitable for precision parts processing.
- Motor power: Grinding motor power determines the grinding machine's processing capacity and adaptability to different materials. Higher power machines can handle more extensive and harder workpieces.
- Operating system: The operating system includes manual, automatic, and other modes, which determine how the machine is operated and controlled.
Maintenance of cylindrical grinding machines:
- Regular cleaning: Regularly clean the surface, workbench, and grinding head of the machine. Use a soft brush or a vacuum cleaner to remove the grinding debris. At the same time, pay attention to the removal of the cooling holes and the drainage holes to prevent clogging.
- Lubrication: Lubricate each moving part according to the machine's maintenance manual. Add lubricant to the guide rail, gearbox, bearings, and other parts to ensure smooth operation and reduce friction loss.
- Replace grinding wheels: Replace and adjust the position of the grinding wheels periodically. Ensure that the fixing nut and the alignment degree of the grinding wheel are correct. The grinding wheel should be kept clean and free of foreign objects.
- Electrical inspection: Check the electrical circuits and connectors. Ensure that they are firm, reliable, and free from damage. Regularly test and adjust the parameters of the electrical control system to ensure that the machine functions correctly.
- Maintain the cooling system: The maintenance of the cooling system of a cylindrical grinding machine is critical to its proper functioning and overall longevity. The coolant not only prevents overheating during the grinding process but also aids in achieving a smooth surface finish on the workpiece. Hence, it's essential to regularly check the coolant level and refill it if necessary. The type of coolant used should also be appropriately selected based on the grinding process and the material of the workpiece. Furthermore, ensuring that the coolant delivery system is free from clogs and operates effectively is vital for consistent coolant flow. Regular maintenance of the cooling system can prevent potential damage to both the grinding machine and the workpiece.
- Periodic maintenance and repair: Regular maintenance and repair of cylindrical grinding machines is crucial for ensuring their precision, efficiency, and longevity. Establishing a periodic maintenance schedule allows for timely inspections, adjustments, and replacements of key components such as bearings, gears, and transmission systems. This helps in preventing unexpected breakdowns and reduces the risk of damage to the machine. Additionally, routine maintenance ensures that the grinding machine continues to deliver high-precision machining results, thereby maintaining the quality of the workpieces. Regular maintenance and timely repairs can also extend the service life of the machine, reducing the need for frequent replacements and thereby saving costs in the long run.
Scenarios of cylindrical grinding machines
The types of usage scenarios for cylindrical grinding machines are numerous and varied because these machines are core components that support many industries' production processes. Among them, the usage scenarios of the machining industry alone are already extensive. Just to name a few, here is an extensive application area chart of cylindrical grinding machines and their corresponding usage industries.
- Machining of tools: One of the primary uses of cylindrical grinding machines is to grind various tools. This includes not only common cutting tools such as drill bits and reamers but also complex tools like threading tools and circular cutting tools.
- Automobile manufacturing: In the automobile manufacturing sector, cylindrical grinding machines are used to process components such as gear shafts, axle shafts, crankshafts, cylinders, etc. Achieving precise fitting and sealing, ensuring the quality and durability of automobiles.
- Electronic industry: In the electronic industry, cylindrical grinding machines are used to process the shells and internal parts of various electronic products, as well as parts of precision instruments. These include items such as connectors, capacitors, precision shafts, and more.
- Aerospace industry: The cylindrical grinding machine is also widely used in the aerospace industry. The key aerospace components, such as turbine shafts, landing gear, rocket nozzles, and valve seats, are all processed with the help of cylindrical grinders.
- Medical devices: Medical devices have to reach high precision and quality requirements to ensure the health and safety of patients. Therefore, the parts of medical devices, such as orthopedic implants, bone fusion devices, and dental implant fixtures, are usually processed with a cylindrical grinding machine with high precision and reliability.
How to choose a cylindrical grinding machine
When purchasing a cylindrical grinder machine for sale, buyers need to look at its construction and safety features carefully. Generally, these machines need to have a tight construction to prevent any vibration when the spindle is rotating at a high speed. Such a quality allows the grinding precision and stability of the workpiece. It also helps to extend the lifespan of the grinder machine.
Burrs, sharp edges, and any other obstacles that could hinder the proper functioning of the machine should be eliminated during the process of assembly. All parts must fit well together. Doors and hatches should align precisely. All fasteners and fittings must be secure. Loose parts can shift or come undone and therefore, may pose safety hazards.
Another thing to look at is the protection devices. The grinder machine ought to have guards to cover belts, pulleys, and moving parts. Also, look for load breaks or overload protection that can prevent product failure due to electrical overload during functioning.
Insurance coverage for product liability or recalls is also advisable since it compensates the buyers in case they incur any losses or additional costs.
Good quality cylindrical grinding machines usually have a manual included to explain the machine's working parts, how to operate it safely and effectively, maintenance practices, troubleshooting guide, and safety precautions. The manuals are essential. However, buyers need to ensure that the manuals include detailed information in language and illustrations that are easy to interpret.
Finally, to be on the safer side, buyers should choose cylindrical grinding machine suppliers with positive reviews and a good reputation in the market. Take time and read through various reviews to ensure that many people are satisfied with their services and products.
Cylindrical grinding machine FAQ
Q1: What are the shining benefits of cylindrical grinders?
A1: The precision of cylindrical grinders is unmatched. Even the tiniest tolerances can make a big difference in certain industries. By creating parts with very close tolerances, cylindrical grinders help ensure that machines work properly and don't break down. Cylindrical grinding machines are also very efficient. Once a part is set up in the machine, it doesn't take long for the grinder to do its job and produce part after part. This means cylindrical grinders can make lots of parts in a short amount of time, which helps factories run smoothly and keeps costs down.
Q2: What are the main differences between external and internal cylindrical grinding machines?
A2: External cylindrical grinding machines focus on grinding the outer surface of cylindrical workpieces, such as shafts, rods, and tubes. On the other hand, internal cylindrical grinding machines are designed to grind the interior surfaces of cylindrical objects, such as holes and tubes. Furthermore, the setups used for grinding also differ between the two types. External workpieces are generally held in a chuck, collet, or between centers, while internal ones are typically supported by a mandrel or core holder.
Q3: Do cylindrical grinders only work on metal materials?
A3: No, cylindrical grinders can also work on non-metal materials like ceramics, composites, and some plastics. Nevertheless, the grinding process and wheels used may vary for different non-metal materials.
Q4: Is operator safety considered when using cylindrical grinding machines?
A4: Yes, operator safety is a top priority when using machines like cylindrical grinders. These machines can be very dangerous if not used properly. Protective equipment like grinding goggles, earmuffs, protective masks, and safety shoes should always be worn when operating a grinder. Proper PPE ensures the operator is safe from any potential hazards the machine may present.
