Abrasives are used in various cutting, grinding, and polishing applications, and usually form part of a process to produce some kind of finished product.

At Grinding Techniques choosing the correct mineral is essential in producing premium quality abrasives. For centuries, minerals have been an essential part of the industrial world, available in many forms, including grains, powders, and bars.

Popular minerals used, include Aluminium Oxide, Silicon Carbide, Zirconia Alumina and Ceramic, with Aluminium Oxide as the most commonly used abrasive mineral. Its composition is hard and durable making it suitable for grinding and cutting applications of many materials, including steel, ceramics, and various other materials.

For ferrous metals like stainless steels and other high temperature alloys, a synthetic mineral- Zirconia Alumina is more suited. Zirconia Alumina carries self-sharpening properties, making it an excellent choice for abrasives that need to produce high and fast stock removal on application.

A synthetic mineral with a hardness similar to Aluminium Oxide but with a much better heat resistance, is Ceramic Alumina, one of the latest innovations in grain technology. Due to its fast-cutting rate and self-sharpening properties, it is known as one of the premium minerals, making it ideal for applications on heat sensitive metals, hard metals and alloys. Abrasives manufactured with Ceramic grain will deliver the ultimate in performance, with an aggressive, consistent cut under moderate to high pressure that provides extremely consistent stock removal.
This high-performing grain features very small fracture planes which allow each grain to constantly re-sharpen as is wears away, providing fast cutting action throughout its usable life. They provide the best in longevity and produce the highest cut rate of all when it comes to abrasives.

Ceramic grain is known as a manufactured or artificial abrasive mineral whereas Emery and Garnet are examples of natural abrasives that is found in nature. Artificial abrasives are produced scientifically through various processes, creating a newest technologically advanced mineral with specific qualities that natural minerals do not have.

A chemical procedure of creating a colloidal solution referred to as sol is used. This solution basically contains tiny particles of Aluminium Oxide in a liquid medium. For easy reference one can think of caramelised sugar. In its natural form sugar has fine granules, but once mixed with water it becomes a liquid-like structure that still contains all the tiny granules.
Ceramic Alumina is a result of the sol-gel process which is created by particles of Aluminium Oxide in the sol mixture. The mixture is then dried under controlled temperatures resulting in the mineral releasing from the bonding agent.

The final step in creating ceramic abrasive grain is the sintering process. Heat treatment causes the powdered grains to shrink making them stronger and denser.

Ceramic grain is a friable abrasive, which allows it to fracture continuously when exposed to heat and pressure in the grinding process, continuously exposing new and sharp cutting edges throughout its lifetime. This ensures that a very consistent metal removal rate and surface finish is achieved over longer periods of time.

Should a cutting-or-grinding application involve exotic materials such as superalloys or stainless-steel, Grinding Techniques range of ceramic abrasives is sure to outperform most other abrasive minerals. Due to its self-sharpening ability and severe toughness, ceramic grains will not dull as quickly as other conversional grains, and due to the fast-cutting action of ceramic grains, the material removed is far superior to any other conventional abrasive grain in the same amount of time.

Other minerals used in the manufacturing of abrasives, include Silicon Carbide (SIC), a hard and brittle mineral, particularly suited to applications on non-ferrous metals. Known as the hardest natural mineral, and available in various forms, Diamond is used for cutting and grinding applications on very hard materials such as glass and ceramics.

Similar in hardness to Diamond, is Cubic boron nitride (CBN), a synthetic mineral used in abrasives for applications on hard materials like steel and ceramics, very popular for applications in the automotive, aerospace and metalworking industries.

Whatever abrasive is manufactured, the choice of abrasive mineral always depends on the workpiece material, desired finish, and the specific application.

As technology advances, Grinding Techniques utilises the latest in mineral and abrasive formulations specifically developed to meet the changing needs of industries.

At the cutting edge of technology, Grinding Techniques only use the best in raw materials, when manufacturing abrasives. Numerous parameters have been defined with a view to enhance production and is substantiated by quality insurance measures after every manufacturing step for each product. All our products are manufactured in accordance with ISO standards, and we continually strive to consistently meet and exceed maximum standards to ensure compliance with strict customer requirements.

For a custom solution to your application, contact one of our Application Specialists.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

The metals casting, or foundry operation is an amazing and intriguing process where abrasives play a very important role throughout the entire foundry process.

Although the focus may have shifted from casting bells and cannon barrels to products that influence our daily lives like the engine block in your vehicle to the impeller in the pump at the water purification plant supplying water to your city or town right to the gears and components driving the wind turbines powering our homes….

With processes becoming more mechanised and controlled, throughput and quality remains the most critical elements in the foundry process, although the fundamentals of creating a masterpiece in metal has for the most part, remained unchanged. The foundry process is started with a design concept and created from an engineering need for a metal casting, be it sand moulded, die cast, investment or spun (centrifugal) cast.

Based on the design and type of casting method selected, tooling in the form of a pattern may need to be manufactured. These patterns are mostly made from wood, “housing” the sand, and resembling the positive impression of the casting as well as any cores that may be required. Abrasive solutions used in this process include coated abrasives in sheets, rolls and discs, for primary and secondary finishing of wooden and metal parts.

Grinding Techniques offer a complete abrasive basket that caters for all the Foundry applications and more.

Once the pattern and its various components have been completed, the moulding process will follow. In a foundry, where the pattern is filled with sand, cores are placed for funnels and channels in order to direct the flow of molten metal into the mould.

Following the sand process, is possibly one of the most dangerous, but also most exciting part of the process – the Melt.

Metal is added to a furnace and melted down to liquid form making it pourable. Included in this melt can be scrap metal, raw virgin metals, and or a combination of both, creating the desired alloying materials that may be required. The melting process also provides an opportunity to remove any contaminants in the mix. When using scrap metal in the melting process it is vitally important to use high quality, fit-for-purpose abrasive cutting discs for chopping metal scraps to eliminate some of the contaminants, before melting. It is equally important to select metal specific abrasive products to eliminate any potential contamination (such as processing Aluminium scraps with products that contain ferrous contaminants). Once the metal has reached the desired melt stage and has been tested for chemical make-up and impurities, the molten metal can be poured. This is when the moulds are filled with the glowing hot metal and allowed to cool.
Depending on the type of metal and the size of the casting, the cooling period can range from a few minutes to several days. Once sufficiently cooled and solidified, the fresh castings will be removed or ejected from their moulds and potentially shaken to remove all the remaining sand or other moulding materials. One such technique for initial cleaning is shot blasting. At this time, the sprues, gates, and risers can either be broken off or cut off with abrasive cutting discs. Depending on the size, either angle grinders or larger, engine driven machines can be used with cut-off discs to remove the excess. Rough grinding of any burnt-on sand can also be done by using a specialist angle grinding discs. The Superflex and Andor range of products boasts an extensive range suitable to any cutting or grinding application.

Following the initial cleaning process the casting now needs to be fettled for further processing. Where large amounts of material need to be removed, resin bonded snagging wheels are the industry standard. Depending on the metal cast, these are manufactured with a number of abrasive grains. Newer technology Ceramic grains are proving to be the premium go to product as their stock removal rate is substantially higher, while keeping the casting much cooler. Smaller areas of metal removal can be conducted by utilising a handheld abrasive angle grinding discs, also available in various grit and grain derivatives depending on the metal and application. For very small or hard to reach areas, we offer various shapes and sizes of abrasive mounted points and tungsten carbide burrs.

The next phase, checking and inspection allows for visual and or x-ray inspections, die-penetration tests (especially on heat sensitive metals) and other non-destructive tests. Castings are also measured for accuracy and selective destructive testing to check may be conducted for internal porosity, inclusions and or shrinkage dependent on the requirement.

Not all castings are finalised at the rough stage though, some castings require further machining to achieve the desired result. Milling and turning can be done to extreme tight tolerances on CNC machines. Some components that require an abrasive finishing, such as automotive crank shafts must be ground and polished, first with a vitrified bonded abrasive grinding wheel and then with coated abrasive belts.

Cylindrical components can be internally and or externally ground with various sizes, grades, and grits of abrasive grinding wheels. Large surfaces that need to be absolutely flat can be surface ground with abrasive wheels, cups or segments. These abrasive products are made from a range of conventional (Aluminium Oxide, Zirconium Alumina, Ceramic) and super (diamond, CBN) abrasives based on the application and end product requirement. Non-woven and mounted abrasives are available for applications requiring finer, more precise finishes, and where smoothness to the final finish is imperative, polishing points are also available for super-finishing of dies.

Our abrasive basket offers complete solutions to all Foundry markets. Our products are Locally manufactured with only the best raw materials, for maximum output, we offer the perfect balance between cost and performance.

With Superior products, Specialist advice and excellent service and stock levels, trusting Grinding Techniques in YOUR foundry process will make the difference.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

When it comes to choosing the correct abrasives for your hand tools, it is important to know your application, and the desired results you would like to achieve.

Not only will the correct abrasive ensure the longevity of your hand tool, but it will also result in a high performing application and successful completion of any job.

One of the most important factors to consider when it comes to abrasives, is the type of material that will be used for the application. imperative to use the correct abrasive
The abrasive market carries a wide range of products specifically manufactured for applications on both ferrous and non-ferrous metals, where it is important to note that manufacturers will always indicate the suitable material on the packaging labels of their products.

This information is of great value to ensure the right abrasive is used on the right material to avoid contamination during application which can easily occur when using the same abrasives on multiple materials.

A common misconception is that Stainless Steel cannot rust. The same is often true for Aluminum. While the actual oxidation process is different to “normal” steels, these metals can still oxidise (rust) if not handled and processed correctly. With Stainless Steels, normal oxidation creates a thin barrier or film like layer on the surface, called Chromium oxide. Unlike mild Steel rusting, the Chromium oxide layer sticks to the metal, thereby protecting it. If this layer is stripped off, the metal will rust. High quality grade Stainless Steel, with a higher Chromium content will have better protection from this unwanted oxidation. Abrasives suited for Stainless Steel are manufactured free from Iron, Sulphur, and Chlorine to ensure a contamination-free application. To avoid carbon contamination which causes rusting with moisture exposure, it is suggested that a new disc is used when starting an application on Stainless Steel after working on Mild or Cast steels. Non-ferrous metals like Copper and Aluminum, which are softer but harder to grind require abrasives that will not burn, contaminate, or discolor the material. The most common stumbling block when working with these materials, is clogging of the disc that will cause the disc to glaze and stop grinding and or cutting.

Establishing the right abrasive for the intended application is another important factor to consider. With so many available options, it is important to distinguish between the results delivered by various products.

If your application involves abrasive cutting just to separate material, a normal conventional cutting disc could be the obvious choice, but if you are looking to have reduced material wastage, less burr formation, and more cuts, a slimline or thin cutting disc ranging with a thickness between 1-and-2mm would be the best choice.

For fast stock removal applications, the general choice has always been abrasive grinding discs. If your end-product will be painted, coated, or polished it generally requires a smoother finish, a flap disc might be the best. Available in two types and different grits, they can be used for a range of applications. The Type 27, also known as flat, is ideal for blending, smoothing, and finishing while the Type 29 has a more conical appearance offering a greater contact area, making it perfect for aggressive stock removal.

Another popular application with hand tools, is sanding. Random Orbital Sanders, Sheet Orbital Sanders, Detail Sanders, and Belt Sanders are some of the most used power sanders. A wide range of abrasive sanding discs and sheets are available in different grits to allow for applications ranging from stock, paint, and rust removal to finishing and blending. Considering all these factors when it comes to choosing abrasives for your hand tools, it is also important to note the precautionary safety measures that need to be actioned when working with abrasives.

Manufacturers will always indicate what type of PPE (Personal Protective Equipment) to wear during applications to ensure maximum safety to the operator and a safe operation.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

Bonding systems play a critical role in the performance of precision abrasives and can be seen as the “glue” that keeps everything together.

A high-quality bonding system holds the grain in place up to the optimum point where the grain is held just long enough for it to get blunt, and then to release the dull grain, in order to expose new sharp grains to continue with the cutting operation. A poor bonding system, however will release grain too early during operation which is also known as premature grain shedding, however where a bonding system holds the grain in place for too long, it will start glazing and eventually burn the material, resulting in an increase in dressing cycles between grinding operations, leading to a rise in “lost time and inventory on grinding media”.

Two of the most popular bond systems – Vitrified and Resinoid products, can be distinguished with the letter V for Vitrified, and the letter B, for Resinoid as part of the product specification.

With both bonds being equally suitable for various applications, each one has certain characteristics that sets it apart from the other.

A vitrified bond is constructed from different types of clay and grains and are fired in a kiln at temperatures typically above 1250 degree Celsius. During this firing operation the clay or feldspar bonds with the grains around it. During the cooling process, each grain is surrounded by a glass like material which strengthens the bond and adds to the wheels’ overall rigidness. With these characteristics a Vitrified precision bonded wheel is perfect for applications requiring high stock removal where precision tolerances are required.

These wheels are often referred to as glass like in nature, as they are not able to handle any shocks or blows, compared to a Resin bonded wheel which are more rigid and resistant to shocks or blows.
Although not as rigid, Vitrified bonded wheels can be stored indefinitely, as they are not affected by water, or variations in temperature, while Resin bonded wheels are affected by alkali, humidity, and extreme weather conditions, resulting in deterioration of the bond over time.

Resin bonded systems are constructed from Phenolic resins and different types of fillers which gives it its characteristics. It is cured in ovens between 150 to 200 degrees Celsius, making it tougher but less rigid than a Vitrified bond, and suitable for precision grinding applications running at high speeds, necessitating high stock removal.

While Vitrified bonds break away under pressure during application, Resin bonds require heat to break away.

In some cases, when insufficient pressure is applied during operation, Vitrified bonds will clog, as the bond cannot break away to expose new sharp grain at the optimum point on application. This can easily be rectified by increasing the pressure or infeed rate during the grinding operation.

When Resin bonded precision wheels are exposed to too much heat during operation, the bond system will break away too rapidly at the point of contact. To rectify this, coolant can be increased to keep both the workpiece and grinding wheel as cool as possible. It is of utmost importance to maintain any coolant when the acidity level creeps up, as a too high acidity level will attack the bonding system, causing it to break away prematurely. Cleaning out the whole coolant system and replacing it with a mixture at the correct percentages will alleviate this during application.

To ensure precision grinding applications are served with the best in bonding systems, it is important to partner with a supplier that understands these factors.

Grinding Techniques have been locally manufacturing Andor precision abrasives for over 40 years. With our Research and Development team on site, we are constantly innovating and testing our products to ensure that we stay at the forefront of cutting edge abrasives.

Contact our Application Specialists today for a bespoke solution to your Precision grinding needs.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

Grinding Techniques carry an extensive abrasive range for surface preparation that will turn anyone into an expert.

After completing various sections of welding metal together, the next step is achieving a seamless finish.

Blending welds is the action of combining two metal pieces together through welding and the grinding down of the weld to produce no visible seam.

Before welding can commence, the workpiece needs to be cleaned to remove any rust or mill scale that has formed. For this application, the Superflex rough cleaning, or non-woven flap disc is ideal. Once the cleaning process is completed you can determine the type of weld that is required.

2 Types of welds can be distinguished. MIG welding, also known as Gas Metal Arc Welding and TIG welding, known as Tungsten Inert Gas Welding. Where MIG welding is known to be a low cost yet highly productive method of welding, and mostly used on common metals like Carbon Steel and Alloys, TIG welding is a more precise form of welding and requires a bit more skill, as it results in a neater and smaller weld.

The choice of weld will be dependent on the required finish, which is determined by the original material of the workpiece. Carbon steel is almost always painted after welding, where Stainless steel usually requires a polished finish. If working on Carbon steel, not all welds need to be removed, as the seam will not always be visible. Stainless steel, like elevator panels, or handrails on the other hand requires a highly refined finish to disguise scratches.

When preparing to blend a weld, it is important to ensure that you are working with a clean, good weld, free from air bubbles or porosity. There should also be no undercut for example edges that doesn’t intrude or fold into the surface of the material.

The Superflex range consists of different product options when it comes to blending weld applications. Removing the weld can quickly be accomplished with our AS30R Professional grinding disc.
We recommend, a criss-cross motion to knock down the high spots when grinding, as you will remove stock quicker and easier without damaging the workpiece around the weld.

It is important to refrain from too much pressure when using a grinding disc, as you wouldn’t want to grind into the weld causing damage that could potentially weaken the weld leading to it needing to be redone. In some cases, a used grinding disc might offer the perfect solution, as it will be less aggressive on application. It is important to note that the final required blend will require further rework with a finer grit abrasive product after grinding.

If opting to use only one product, the Flap disc, is ideal to remove both the weld and produce the final blend.

As a third option to blend welds, Superflex Fibre Discs can be used. A P80 grit used at a really low grinding angle of about 45 degrees, will blend the weld perfectly. Once satisfied with the finish, you can use a finer grit fibre disc, either P120 or P150, to remove the scratch marks either . Take care not to use excessive pressure during this application.

The surface is now perfectly prepared for painting, however if a mirror finish is required, we suggest using a Superflex Non-woven Medium Flap disc followed by a Superflex Non-woven Fine Flap disc.

Whatever your requirement when it comes to abrasive products, we have you covered.

Contact us today for a bespoke solution to all your application needs.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

Mounted points are always in high demand when precise results are required on difficult-to-access areas. Mounted points are used in conjunction with Straight grinders or Die grinders as it is commonly known. These power tools are hand-held and used for grinding, sanding, honing, deburring, or machining of material. The name stems from one of their earliest applications; tool and die work, where they are used to create the precise contours of dies and molds. Their versatile application, make them a popular tool.

When it comes to mounted points, they are very small vitrified, or resin bonded abrasive points with a ball, point, cone, cylinder, or bullet shape. Mounted on a pin or mandrel to suit a Die grinder.

Superflex carries an extensive mounted point range available in A, B and W shapes with 3mm and 6mm spindle (shaft) diameters. Our range offers both resin and vitrified bonded variants in different specifications, dependent on what your applications and results require. Our resin and vitrified bonded points offer you solutions for the highest quality requirements. Some of the wide range applications require ceramic points that strike a perfect balance in terms of chip performance, surface finish and longevity. Ceramic points are often used in foundries and mold making. For fine machining, our range also includes elastic and polishing points tailored to your needs.

To best achieve your result in the most cost-effective way, a few factors need to be considered when selecting the correct mounted point for your application. The abrasive grain type, grain size, bond type and performance parameters for the application would be all key factors to success.

Mounted points differ in terms of abrasive grain type and abrasive grain size. Different abrasive grain types include Aluminium oxide, Ceramic, Silicon carbide and Alumina-zirconia. Abrasive grain size is usually specified according to FEPA standards. The three main performance specifications for mounted points and cones are rotary speed, shank diameter, or bore inner diameter (ID) and outer diameter (OD). Rotary speed is the maximum speed recommended by the mounted point manufacturer. The bore is the ID of the center mount of the abrasive product and is used to secure the abrasive product onto a spindle or mandrel. The shank diameter is the OD of the pin or shaft of the mounted point or wheel. When selecting mounted points, the shape and OD of the product should also be considered.

When looking at vitrified bonded mounted points the Superflex range of Aluminium oxide, ruby mounted points offer a coarser grit which can break down rapidly – Ideal for cutting and removing metal and best suited for steels and cast steels. This specification works well on cast iron, hardened and tempered steels, as well as welding seams on alloyed and tool steels. The finer Aluminium oxide pink range of Superflex mounted points is a hard stone that retains its shape and leaves a fine surface finish – Best suited to steels and cast steel.
Silicon Carbide mounted points are ideal for Cast iron, Non-ferrous steel, Non-metallic material, brittle and hard Carbide, glass, gem, and stone grinding, or honing. Both green and black Silicon carbide variants are available under the Superflex range.

Ceramic vitrified and resin bonded mounted points are the best available technology within the Superflex range. These mounted points are the most versatile choice for high volume foundry operations. The unique, engineered Ceramic grain shape combined with the latest technology bond type provides the highest metal removal rate with a longer product life span compared to Aluminium oxide and Silicon carbide grain type products. With a much cooler cut and preventing loading, Ceramic mounted points are ideal for deburring, blending, and finishing whilst creating a very uniform finish.

Despite their small size, mounted points should be used with all the safety precautions recommended for other types of abrasive grinding wheels. Each point should be inspected before use to make sure that the spindle has not been bent or the point damaged. When mounting, the spindle should be inserted into the collet as far as possible. The pressure exerted in the grinding operation should not be excessive. Mounted points should be operated with the recommended speed to achieve efficient grinding action. The factors that affect the maximum safe operating speed of a particular size wheel include.

• The size and shape of the mounted point
• The overhang (distance that the wheel is extended from the collet)
• The diameter of the spindle on which the wheel is mounted
• The condition of the grinder and it’s collet.

The use of mounted points can produce dust. Take normal precautions to avoid exposure. Always wear face protection. It is good practice when operating portable grinders to hold the grinder down and away from the operator until full operating speed is attained and it is determined that the mounted point is properly mounted and running smoothly. Do not operate a mounted point which is not properly mounted and running true. If excessive vibration is felt, stop the grinder immediately and do not resume grinding until the cause is found and corrected.
As local manufacturer, Grinding Techniques is committed to deliver premium quality products to the market and provide a specialised abrasive solution for your application.
Contact our Business Development Team for more information on our products or for a bespoke solution for your business application.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

When it comes to Precision grinding, chatter marks can pose a real challenge, especially with the pressure of meeting production deadlines. This problem is typically only identified when products get to the QC stage for quality inspection, and parts have already been ground within the required tolerance. Identifying the problem at this stage of production leads to unnecessary costs as parts usually must be scrapped or reworked.

As common as this scenario is, it is paramount to correct the problem in avoidance of incurring extra costs. With over 40 years of experience in local manufacturing of specialised abrasives, we at Grinding Techniques, understand both the cost, and other implications of this phenomena. Our Research and Development team in conjunction with our Business Development Team can provide a range of solutions on how to avoid chatter marks with practical options of how to counteract this, should it occur during production.

The following steps may be taken but it should be noted that one must try one step at a time.

Reviewing grinding fluid for its cleanliness and for instance increasing the mixture from perhaps a 3% to around 6 – 7% could minimise chatter marks during application.

Secondly, checking for any possible machine vibrations that could aid in the creation of chatter marks during application should be considered. This could be from within or around the machine and even from other machinery in the vicinity that could cause floor vibrations to be transferred to the grinding machine during application, this should be eliminated at all costs. The grinding machine’s belts should not be damaged and should be tensioned correctly and spindle bearings should not have any play or be worn. Make sure that the spindle bearings of the machine are not worn, if there is any play on the spindle bearings, replace them immediately.

One other major cause of chatter marks usually results from taking too big of a cut by simply reducing the infeed of the grinding wheel and allowing for a lighter cut from the material or slowing down the traverse speed should assist you in reducing or eliminating chatter marks.

Another common cause of chatter marks is grinding wheels acting too hard, the general rule of thumb in grinding is to use a grinding wheel with a soft grade on harder materials and a harder grade wheel on softer materials. When a grinding wheel acts too hard, there are two possibilities to fix the problem either change the specification to a softer grade, if the job doesn’t need to be ground urgently or make the wheel act softer by firstly slowing down the speed of the wheel generally, for every 5 M/S that you decrease the grinding wheel speed, it will act one grade softer, or one grade harder when increasing the speed of the grinding wheel. If this is not possible the workpiece speed can be increased. This will enable the wheel to break down more and act softer. Alternatively, the infeed rate of the grinding wheel can be increased. It is however important to remember that a vitrified wheel breaks down under pressure. Taking too light of a cut will just cause the wheel to rub against the surface of the grinding wheel and will lead to l clogging. By increasing the infeed, more pressure is added which will allow the wheel to start breaking down.

If you are traverse grinding, increase the traverse speed of the grinding wheel, this will make it break down more. A final way of making the wheel act softer on application is to decrease the diameter of the grinding wheel, as a wheel gets smaller, the peripheral speed of the grinding wheel decreases, allowing it to act softer.

Another approach is to make changes to your dressing parameters. By taking a heavier cut, and increasing the traverse rate of the dresser, the wheel will open and make it cut more freely, but this will however leave a rougher surface finish. Grinding the part in two stages, first rough grinding and leave a little bit of material on the part, and then moving over to a finishing grinding process to close the face of the wheel slightly to get the desired finish should assist you in obtaining the correct finish.

By taking some of these precautionary measures, chatter marks can be minimised, if not completely avoided during application. Whatever assistance you require when it comes to precision grinding, our application specialists at Grinding Techniques are ready and available to assist you with any concerns or advise you might require.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

Ceramic abrasives are one of the latest innovations in grain technology. This high-performing grain features very small fracture planes which allow each grain to constantly re-sharpen as is wears away, providing fast cutting action throughout its usable life. They provide the best longevity and highest cut rate of all coated abrasives. The ultimate in performance, with an aggressive, consistent cut under moderate to high pressure that provides extremely consistent stock removal.

Ceramic grain is known as a manufactured or artificial abrasive mineral whereas Emery and garnet are examples of natural abrasives that is found in nature. Manufactured or artificial abrasives are produced scientifically through various processes, creating a newest technologically advanced mineral with specific qualities that natural minerals do not have.
So how is ceramic alumina made?

A chemical procedure of creating a colloidal solution referred to as sol is used. This solution basically contains tiny particles of aluminium oxide in a liquid medium. For easy reference one can think of caramelised sugar. In its natural form sugar has fine granules, but once mixed with water it becomes a liquid-like structure that still contains all the tiny granules.

Ceramic alumina is a result of the sol-gel process which is created by particles of aluminium oxide in the sol mixture. The mixture is then dried under controlled temperatures resulting in the mineral releasing from the bonding agent.

The final step in creating ceramic abrasive grain is the sintering process. Heat treatment causes the powdered grains to shrink making them stronger and denser.

Ceramic grain is a friable abrasive, which allows it to fracture continuously when exposed to heat and pressure in the grinding process, continuously exposing new and sharp cutting edges throughout its lifetime. This ensures that a very consistent metal removal rate and surface finish is achieved over longer periods of time.

Typical applications where ceramic abrasives would be beneficial, could include but is not limited to tough and hard to grind materials, heat and burn sensitive materials and applications where the output of parts in high volumes within the shortest time possible is a requirement.

Should a cutting-or-grinding application involve exotic materials such as superalloys or stainless-steel then ceramic abrasive minerals is sure to outperform most other abrasives. Due to its self-sharpening ability and severe toughness, ceramic grains will not dull as quickly as other conversional grains, and due to the fast-cutting action of ceramic grains, the material removed is far superior to any other conventional abrasive grain in the same amount of time.

Grinding Techniques, a proudly South African supplier and manufacturer of specialised abrasives and a converter of coated products, offer ceramic abrasive technology through our partnership with Starcke and Deerfos.

The quality of coated abrasives depends on numerous parameters such as the amount of grain and weight per unit area, the quantity of base and topcoat as well as curing temperatures. These parameters have been defined with a view to production and is substantiated by quality insurance measures after every manufacturing step for each product. Not only do we manufacture abrasive products according to ISO standards, but we also strive to consistently meet and exceed maximum standards to ensure compliance with strict customer requirements.

As part of the Tyrolit Group we are able to offer a wide range of products for almost every kind of application., our aim to provide the best coated or bonded abrasive products for your manufacturing process, actively, objectively, and reliably.

Coated abrasive products supplied by Grinding Techniques are designed to give the finishing touch to a wide variety of materials including a wide range of metals, wood, stone, glass, plastics ceramics, and rubber. We are able to cut to all shapes, lengths, and widths according to customer requirements.

Contact us for the latest innovation in coated abrasives. Training and technical assistance is available from our product specialists who are ready to provide solutions to all your questions and processing issues.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

When it comes to choosing the correct abrasives for your hand tools, it is important to know your application, and the desired results you would like to achieve. Not only will the correct abrasive ensure the longevity of your hand tool, but it will also result in a high performing application and successful completion of any job.

One of the most important factors to consider when it comes to abrasives, is the type of material that will be used for the application. imperative to use the correct abrasive. The abrasive market carries a wide range of products specifically manufactured for applications on both ferrous and non-ferrous metals, where it is important to note that manufacturers will always indicate the suitable material on the packaging labels of their products.

This information is of great value to ensure the right abrasive is used on the right material to avoid contamination during application which can easily occur when using the same abrasives on multiple materials.

A common misconception is that Stainless Steel cannot rust. The same is often true for Aluminum. While the actual oxidation process is different to “normal” steels, these metals can still oxidise (rust) if not handled and processed correctly. With Stainless Steels, normal oxidation creates a thin barrier or film like layer on the surface, called Chromium oxide. Unlike mild Steel rusting, the Chromium oxide layer sticks to the metal, thereby protecting it. If this layer is stripped off, the metal will rust. High quality grade Stainless Steel, with a higher Chromium content will have better protection from this unwanted oxidation. Abrasives suited for Stainless Steel are manufactured free from Iron, Sulphur, and Chlorine to ensure a contamination-free application. To avoid carbon contamination which causes rusting with moisture exposure, it is suggested that a new disc is used when starting an application on Stainless Steel after working on Mild or Cast steels. Non-ferrous metals like Copper and Aluminum, which are softer but harder to grind require abrasives that will not burn, contaminate, or discolor the material. The most common stumbling block when working with these materials, is clogging of the disc that will cause the disc to glaze and stop grinding and or cutting.

Establishing the right abrasive for the intended application is another important factor to consider. With so many available options, it is important to distinguish between the results delivered by various products.

If your application involves abrasive cutting just to separate material, a normal conventional cutting disc could be the obvious choice, but if you are looking to have reduced material wastage, less burr formation, and more cuts, a slimline or thin cutting disc ranging with a thickness between 1-and-2mm would be the best choice.

For fast stock removal applications, the general choice has always been abrasive grinding discs. If your end-product will be painted, coated, or polished it generally requires a smoother finish, a flap disc might be the best. Available in two types and different grits, they can be used for a range of applications. The Type 27, also known as flat, is ideal for blending, smoothing, and finishing while the Type 29 has a more conical appearance offering a greater contact area, making it perfect for aggressive stock removal.

Another popular application with hand tools, is sanding. Random Orbital Sanders, Sheet Orbital Sanders, Detail Sanders, and Belt Sanders are some of the most used power sanders. A wide range of abrasive sanding discs and sheets are available in different grits to allow for applications ranging from stock, paint, and rust removal to finishing and blending. Considering all these factors when it comes to choosing abrasives for your hand tools, it is also important to note the precautionary safety measures that need to be actioned when working with abrasives. Manufacturers will always indicate what type of PPE (Personal Protective Equipment) to wear during applications to ensure maximum safety to the operator and a safe operation.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

The foundry industry has undergone a major transformation in recent years, yet despite the stagnation in steel and iron casting it is generating steady growth with more than 100 million tons.

Meanwhile, non-ferrous metals such as aluminum and magnesium alloys are increasingly coming into focus with foundries servicing an extremely diverse range of markets. Automotive manufacturers account for approximately 55% on the ferrous side and over 84% on the non-ferrous metal casting side with the second most important customer sector for foundries being general machine construction with around 40 different industry segments.

Innovative developments in cast lightweight components for electromobility and the requirement for improvements in thermomechanical properties demand constant growth and flexible adaption of the cutting and grinding processes. Grinding Techniques, a company of the Tyrolit group provide cutting and grinding solutions through seamless monitoring of the manufacturing process, from the raw material to the finished end product, this enables us to produce consistently high tool quality and at the same time increase the process stability with the growing degree of automation for cutting and grinding applications.

Cut-off grinding is the most frequently used process for removing risers and sprues. Owing to its high efficiency and productivity, cut-off grinding is used in many areas of cast iron and steel production.

Locally manufactured Superflex cut-off wheels impress with exceptional longevity and an attractive price-performance ratio. Our special production processes and comprehensive safety testing ensure maximum work safety and minimum noise levels during application.

When it comes to fettling, high demands are placed on the ergonomics and performance of hand-held grinding tools. All our Andor rough grinding wheels are manufactured to deliver the best high-performing results in every rough grinding application.

Our range of pendular grinding wheels ensure that fettling work can be performed with reduced exertion and higher stock removal rates. In this type of machining, one of the greatest challenges is vibration during application. Through intensive and ongoing development, we are able to supply product into the market with significant reduced vibration levels enabling operators to work more efficiently. Working with an angle grinder is one of the most important processes in foundry sectors for machining all types of metals. When it comes to grinding large and heavy components, we recommend the use of cup wheels, as they are exceptionally robust and durable. The composition of the cup wheels makes them suitable for large area machining of welding lines as well as fast material removal.

When working with cup wheels, it is particularly important to ensure that cup wheels are used only on angle grinders with diameters of 178 mm. smaller machines tend to rotate too fast, while larger ones rotate too slow. In addition, a special protection cover is required to ensure sufficient levels of working safety.

Straight grinders are always in high demand when precise results are required for difficult-to-access areas. Their versatile application options make them a popular tool.
Our vitrified and resin bonded Superflex mounted points offer you solutions for the highest quality requirements. The wide range of applications also requires ceramic points that strike a perfect balance in terms of chip performance, surface finish and longevity. Ceramic points are often used in foundries and mould making.

Apart from versatile mounted points, we also stock a range of tungsten carbide burrs that are made from tried and tested, high quality cemented carbide types on the most modern CNC grinding machines. Our Superflex tungsten carbide burrs are used on a wide range of handheld, pneumatic and electric machines as well as on industrial robots. Thanks to their versatility, they can be used on a variety of materials. To provide a solution at hand for the full spectrum of applications, Grinding Techniques, offers a wide selection of premium quality tungsten carbide burr shapes.

The range easily meets the general demands of economic efficiency, high stock removal rates, simple handling, and excellent longevity.

Grinding Techniques has been the preferred precision grinding partner for decades. With constant innovation, development, and research, we are able to offer a complete bespoke abrasive solution to suit your application.

All our products are manufactured and tested in accordance with International OSA and ISO Standards.

Contact our precision business development team for more information on customised specifications and sizes to suit your requirements.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

Back in the day, some of the first materials to be grinded were metal substances and wood. To grind these particular materials, quartz in combination with sand and flint were used. This was the first type of abrasives utilised. As time progressed, a lot of engineering and grain development was done to produce abrasives to satisfy industry demands.

In 1891 Edward Acheson invented Silicon Carbide, a hard grain in composition, with very good properties to cut or grind materials with low tensile strength such as Tungsten Carbide, Glass and Cast Iron. Only after Silicon Carbide was invented, fused Aluminum Oxide came to the forefront, revolutionizing the industry. Cutting or grinding materials with high tensile strength such as high-alloy steels was now possible and remained the key minerals used in the production of abrasives up until the twentieth century.

As technology evolved around specific materials used by the consumer, different types of fused Aluminum Oxide were produced with White Aluminum Oxide being the purest and most friable of the normal fused Aluminum Oxides. Initially these grains were developed to create sharper cutting edges during cutting-and-grinding applications. In the early 1970’s a new development of synthetics brought about Alumina-Zirconia, a more friable and harder grain that brought the overall grinding performance to a new level when used in bonded wheels, especially on materials with high Chrome content.

In the early 1980’s a new grain “Sol Gel” ceramic was developed. This improved the industry further by performing even better compared to normal fused Aluminum Oxide, and mostly due to the significant self-sharpening properties of the grain, being even more durable.

With time, it was realized that combining a certain percentage of Ceramic grain with fused Aluminum Oxide in the manufacturing of abrasives resulted in grinding wheels with extremely high material removal rates and increased tool life. Due to the self-sharpening properties of Ceramic grain both exceptional stock removal rates and cooler grinds are achieved, making it perfectly suited to materials that are hard to grind.

In the pursuit of developing material technology in order to produce materials with better mechanical properties, such as parts manufactured from wear-resistant materials, requires precision abrasive products that produces closer tolerances with extended product life.

As these wear-resistant parts are generally harder to grind, it is essential to minimise heat input, as exposure to heat will harden these parts even more, potentially causing it to crack.
Although a cooler grind is required, industry also requires to grind these particular parts at a faster rate to reduce overall production costs such as labour, electricity and machine operating costs.

Development in the abrasive industry is continually ongoing, not just on the manufacturing side with a lot more variations in grain combinations to create the ideal grinding wheel for with the “defined cutting edge”, but also with significant development by machine producers to save on production times.

With our Research and Development Team, we are able to locally produce Andor bonded precision grinding wheels with the latest technology in Sintered Aluminum Oxide and Ceramic grain, to support the ever-changing market conditions.

Partnering with Grinding Techniques, will put your business at the forefront of cutting-edge technology, cutting down on unnecessary production time, load on machine and making your company more competitive in the Global market.

Contact our Precision Business Development team today for more information on how we can assist in proving a solution for your application.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

At Grinding Techniques, the safety of our customers is our priority. As a preferred partner to the Construction and Mining industry we are determined to ensure only the best suitable products, manufactured to the highest safety standards, available at the best value for money price-point. Being a Company of the TYROLIT Group, and internationally OSA-and-ISO accredited, we meet all the EN standards, giving our customers peace of mind that we always put safety first.

Tyrolit is a leading European brand of products with a manufacturing facility in Africa for Africa.

Certified abrasive products carry a safety rating that can only be applied after fulfilling a series of strict measures as set out by the Organization for the Safety of Abrasives. The OSA Trademark not only ensures safety during cutting-and-grinding operations but also indicates that products are tested to the highest safety standards giving peace of mind to all users of the products and each product carrying this symbol, can be traced back to its manufacturer.

Specialising in abrasives since 1981 our solution-driven strategy allows you to choose the right tool for the job whilst maximising both your production output and long-term profits.
With our range of cutting and grinding solutions it is an easy decision to obtain the right tool for the job, with all our products boasting longevity, durability and dependability.
When you need a cost-effective cutting-tool for everyday operations, look no further than the 2-in-1 slimline range from Tyrolit.

The Standard two star 2-in-1 disc is perfectly designed for optimum cutting performances on both stainless steel and mild steel. This slimline disc is suitable for use on stainless steel without the risk of contaminating the material. Not only does it offer a cost-efficient solution for your everyday work, but also the safety standards customers have come to expect from Tyrolit products. It puts the power and stability in your hands, designed to cut metal sheets, profiles, pipes, rods and solid bars and rods. The product comes at a great value for money price-point and based on application can save a company on labour and consumable cost.

Tyrolit Standard two star 2-in-1 flap discs offer consistent stock removal throughout its lifetime and is the perfect tool for effortless machining of welding seams as well as edge grinding and surface grinding. Made from a natural fibre core free from fibre glass, this disc is also environmentally friendly. Specifically manufactured for use on both steel-and-stainless steel, it will not contaminate, discolour or burn the workpiece. If your application requires a finishing application with a lower grinding angle, the Type 28A will be the best choice, whereas the Type 27A is best suited to a more aggressive stock removal grinding application.

At Grinding Techniques, we are able to customise solutions for all abrasive cutting-and- grinding operations, whatever your application. Apart from this, our Research & Development Team continually test and evaluate all products to ensure they achieve optimum results safely during application, whilst increasing your productivity and profits.

For more information contact us: 011 271 6400 | info@grindtech.com | www.grindtech.com.

With an estimated 3800 kilometres of petroleum pipeline in South Africa it is safe to say that that the Pipeline Industry is an essential part of the country’s economy.

Numerous manufacturing concerns are involved in this industry, supplying both up and down stream products and services to Government and Private entities in the Petro-chemical and Power-generation markets.

Maintenance of all pipelines are of utmost importance as any breakdown may cause massive disruptions to various sectors including but not limited to Aviation, Industrial, Hospitality and Medical sectors, not to mention the massive impact that it will have on the already fragile business environment.

Repairs and refurbishing of these pipelines and components are an ongoing process and require specialist products to ensure the job is done correctly, thereby shortening the repair time and ensuring better longevity of the pipelines.

A critical area on a pipeline is the joint. When two parts are joined together, it is essential to create a solid joint. In most cases joints are welded together and it is essential that the weld area is without flaws, cracks or defects. In preparation for the welding process a piece of material is bevelled in order to provide better access to the root or inside edge of the material, this bevel area should be finished off with a product that will effectively prepare the surface for welding, while not contaminating it. Some welding procedures will require finishing the bevel with a 120-grit flap disc to best prepare the surface – Grinding Techniques Superflex Flap Discs are perfectly suited to this application and is available in both a flat type 27 and angled type 29 configuration. Once this is done, the welding procedure can commence.

A root run is laid down in the root channel, which will need to be back ground to remove any potential defects like porosity and or poor fusion of the materials. Back grinding is therefore the process of removing the outer part of the weld to ensure that any impurities that floats to the top of the weld is removed before a final weld or cap is added on to “seal” the weld-joint.
Grinding Techniques manufactures various products specifically for this purpose, depending on the thickness of the material and size of the root channel a Superflex 230×4.1×22.23mm AS30T disc is ideal for root channels of approximately 3mm, and a Superflex 230×5.2×22.23mm AS30T disc will suit the requirement for channels wider than 3mm. In the past, most operators would use a 230mm cutting disc for this purpose – the disc would be placed in the section and then twisted to clean and grind the weld out. This is a very dangerous practice and this should be avoided at all cost as cutting discs are not designed to handle this type of side load pressures that they will be placed under. The Superflex back grinding products’ construction allows for much safer work to be carried out.

After completing the welds, the pipe or section will be x-ray inspected for flaws or defects. If the above process is followed correctly, the weld can be passed. If a defect is identified on x-ray, a thinner disc may be required to cut or grind out the material in order to lay down another weld. One such disc is the range of Dual Purpose Cutting and Grinding discs from Grinding Techniques – available in 115×2.2×22.23mm, 125×2.2×22.23mm and 150×3.0x22.23mm, these discs are ideally suited to both cutting and grinding applications. The emphasis here being on the fact that these discs are constructed to be safe when cutting and grinding with the same product. Conventional cutting discs can and probably will break if used in this manner.

The final area that needs to be checked on the joint will be the area between the top of the bevel and the filler cap of the weld. If the weld forms a sharp corner, this may be rejected as it might cause a failure in the weld. The Superflex 115×2.2×22.23 A36S CG (Cut and Grind) is ideal for blending of these areas to ensure a smoother finish and a pass on the inspection.

Conventional thickness grinding discs tend to remove too much material, making the thinner disc ideal for the finer work required. The thinner disc also produces less heat, which is essential for heat sensitive materials that may crack.

One often over looked area of any abrasives is the safety factor. When the incorrect product is used for any application, the potential for disaster is enormous. Grinding Techniques designs, manufactures and tests all products to international standards to ensure that the operator is kept safe, when products are utilised for their intended purpose. The capability also exists for products to be designed for a specific application where no such product currently exists. The products mentioned above all have that focus in mind – create a product that will get the job done quickly, effectively and with the maximum amount of safety possible.