Industrial manufacturing Is getting more competitive as a result of advancement and evolving technology. With the increase in these rapid changes, there have been challenges to manufacturing high-quality parts at the least possible cost and time. Fortunately, the use of CNC machines has made it possible to overcome these challenges, which is the same way CNC grinding system plays an important role in the grinding industry today.
CNC grinding machines that use a rotating grinding wheel are machines tools that help to achieve the removal of material on a workpiece utilizing cutting. They are mostly used for the hard-fine machining of parts. To help you gain more insight into CNC grinding, we have curated the most resourceful guide to grinding.
Read on to learn more!
What is CNC Grinding?
CNC grinding involves removing small amounts of materials via a high-speed abrasive wheel as the cutting tool. This wheel rotates in place while the part or workpiece attached to the machine table moves in the X-, Y-, and Z-axis. While this movement depends on the part size, the grinding wheel may likely take multiple passes to achieve the dimensions desired.
To achieve these, grinding machines are used. These machines have experienced advancement in design, construction, rigidity, and application far more in the last decade in comparison to other standard machine tools in the manufacturing space. Grinding machines fall into five main categories, they include:
- Surface grinders
- Cylindrical grinders
- Centerless grinders
- Internal grinders and
- Special Grinders
Benefits of implementing CNC Grinding
It is important to know that the use of CNC grinding machines comes with numerous advantages. In comparison to traditional grinding, it offers very fine finishes and light cuts to your workpiece. It also provides the possibility of using less skilled labor and limited supervision to perform your projects. There are wide varieties of benefits, they include:
- Large Quantity Production
Irrespective of the size and quantity of the part you are willing to grind, CNC grinding machines fit the bill. CNC grinding machines can run all year round without interruptions. Consequently, you will be able to meet the demands of personal production or client’s production at all times. In short, no amount is too large for the process.
- High Level of Accuracy
CNC grinding machines are known for a high level of precision. You can program these machines to produce fines surfaces and top-quality cuts with high accuracy. The grinding machines will have great finishes in line with the provided specification in the operating software. Due to their operation, you’ll reduce the amount of waste and the possibility of products or parts that do not meet the need they are manufactured.
- Performance Improvement Using Software
CNC grinding machines function on software. All that is required to improve the performance of your machines is to update the CNC software. In a single setup, the latest software offers the possibility of performing many operations. As a result, cutting costs and time-saving becomes feasible in all aspects of production.
- Continuous Production for Longer Hours
CNC grinding machines, like other CNC machines, can run 24/7, 365 days in one year without interruptions. Once set up, the next thing in line is production. The only situation where stoppage can be experienced is during maintenance activities to help achieve proper functioning. This process is limited in time and doesn’t take much time. Hence, the inconvenience of machine breakdown is eliminated.
- Highly Identical Production
CNC grinding offers the possibility of producing identical products in large quantities. This is applicable when bulk production of a part is required. CNC grinders will help you achieve highly similar manufacturing with a uniform resemblance. The end product of such output of using this process will be an exact match to one another.
Common Types of Grinding
1. Surface Grinding
Surface grinding, generally called Hiraken or Heiken, uses a vertical or horizontal axis grinding machine with a circular or square table and a straight type wheel or a cup type wheel. The grinding wheel in this grinding process revolves around a spindle. The workpiece mounted on either reciprocating or rotary table is brought in close contact with the grinding wheel. There are four types of surface grinders they include:
- the horizontal spindle/reciprocating table
- the horizontal spindle/rotary table
- the vertical spindle/reciprocating table
- and the vertical spindle/rotary table.
2. Centerless Grinding
Centerless grinding helps to eliminate the need for center holes for the work holding device or for the work. In this operation, the workpiece rests on a work-rest blade back up by a second wheel named the regulating wheel. Furthermore, the wheel rotation pushes the workpiece down the work-rest edge and against the regulating wheel. Also, the regulating wheel, which is rubber-bonded abrasive, rotates in the same direction as the grinding wheel to control the longitudinal feed of the workpiece when it is set at a slight angle. The workpiece feed rate can be changed by changing this angle and the speed of the wheel.
3. Cylindrical Grinding
Cylindrical grinding involves the process of grinding the outer surface of a cylinder. These surfaces may be tapered, contoured, or straight. In contrast with other CNC operations, this method resembles the lathe-turning operations. They are usually used to replace the lathe when extreme accuracy or superior finish are required, or the workpiece in question is hardened. The grinding wheel that is rotating at a faster rate in the opposite direction is brought in contact with the workpiece as it revolves. The table and the workpiece reciprocate while in contact with the grinding wheel to remove materials from the workpiece.
Accessories and work-holding devices for center-type cylindrical grinders are similar to the ones used on engine lathes. However, universal, independent, and collet chucks can be used on cylindrical grinders if the workpiece contains no center hole or is odd-shaped.
4. Internal Grinding
Internal Grinding involves a similar operation to a boring process in the lathe. Internal grinding machines are used to finish tapered, straight, or formed holes accurately. It functions by holding the workpiece by a work-holding device, usually a collet or chuck, and revolving it with a motorized headstock. Furthermore, a separate motor follows the same direction as the part that rotates the grinding wheel. While it can be adjusted for the depth of cut, it can be fed in and out the workpiece.
5. Special Grinding
Special grinding involves special types of operations and works. Special grinders named for specific processes are used in this case. For example:
√ Tool and Cutter Grinders
These grinders are fashioned to sharpen reamers, milling cutters, taps, and other machining tool cutters. The most popular and versatile tool-grinding machine is the general-purpose cutter grinder. In attachments are various tools for sharpening most types of cutting tools.
√ Thread Grinding Machines
These grinders are special, and they resemble cylindrical grinders. They feature a precision lead screw for producing the correct pitch or lead on a threaded workpiece. The thread grinders offer a way of truing or dressing the cutting periphery of the grinding wheel to build a precision thread form on the workpiece.
√ Jig Grinding Machine
These types of specials are designed to locate and accurately grind straight or tapered holes. They are equipped with a high-speed vertical spindle for driving and holding the grinding wheel. In addition, they use the same precision locating system as in jig borers.
How does a Grinding Machine Operate?
To initiate a grinding process, an operator or a programmer feed the CNC machine’s computer with commands to carry out a specific operation. The machine then uses the commands to move its parts such that the grinding head moves onto the workpiece. Now, know that there are many grinding machines with different techniques for removing materials from a workpiece. An option is to advance the grinding head across or through a workpiece in a slow manner. Another is to move the grinding head that spins at high speed across the surface of a workpiece.
Tips for Effective Grinding
Here are mind-blowing tips that can help you make the most effective use of every grinding operation. These tips will give excellent ideas on how to free your griding bottlenecks. They include:
- Use the appropriate tool for the job: Be sure to use the right grinder to handle the job’s amperage in question effectively. For example, do not use a right-angle grinder of 6 amps for a job that requires amperage ratings between 8 and 10 amps.
- Listen to the grinder to decode if anything is wrong
- Utilize the best coolant system
- Be sure to dress and condition grinding wheels regularly
- Ensure to keep collets clean and in good condition while you use high-quality blanks and correct insert depth into the collet
- Do not neglect the advised maintenance schedule and go thoroughly go through the machine manual
- Ensure that the electrical and air supply to the grinder machine meet the manufacturer’s recommendations
Application of CNC Grinding
Grinding machines feature a wide range of applications, and their applications can be seen in many ways. They include the production of flute grinding, thread and cylinder grinding, grinding milling cutters, surface grinding, contour grinding, broach and hob grinding, reamers, and step-drill grinding, and many more. All these applications are spread across a wide variety of industries, including:
- Automotive industry
- Aerospace industry
- Die or Mold industry
- Machine tools manufacturers
- Medical industry
- Tooling industry and many more
FAQs
1. Are There Any Disadvantages?
Yes, the advantages of CNC grinding operations outweighs the disadvantage. However, the disadvantages include:
- High cost of the tool
- The high price of the process
- Requires high precision
2. Why Choose a CNC High Precision Grinding Machine?
CNC high-precision grinding machines can be chosen due to their application in various materials such as steel, brass, hardened aluminum, bronze, plated aluminum, powdered metals, tungsten carbide, plastics, and titanium alloy. Also, they are the best choice for machining bearings, bushings, shafts, valves, pistons, industrial nozzles sleeves, and industrial needles.
3. Why Are Coolants Necessary in a Grinding Process?
As the grinding process runs, the machine sprays a coolant on the grinding head and workpiece to prevent overheating. Coolant exists in varieties including pastes, oils, gels, oil-water emulsion, gases like air or aerosols. Apart from cooling the grinding head and the workpiece, the coolants maximize the lifetime of the working tip and prevent corrosion of machine parts. While come coolants contain toxic chemicals, biocides, and corrosion inhibitors that can irritate skin or cause respiratory problems, it is important to wear protective gear to avoid exposure to them.
Conclusion
In conclusion, CNC grinding utilizes abrasive techniques for the removal of materials from the surface of a workpiece. This process requires high precision or accuracy to increase the surface quality to get the best out of your machining processes. Irrespective of the grinding, maximizing productivity and getting the best results from your CNC machine is the goal of every dedicated partner. If you desire CNC grinding services for your high precise machined projects, contact RapidDone for all your grinding projects in small or large quantities. We will offer you a decade of experience and professionalism to make your project a successful one. Contact us today if there is such a need!