DEEP HOLE DRILLING INSERTS,LATHE MACHINE CUTTING TOOLS,CARBIDE INSERTS

The last factor is to have some magnetic material for this field with which to interact. In this case, it is a row of permanent magnets. Depending on the coils location relative to the magnet, the current can be adjusted in terms of its strength and polarity, creating a push/pull force on the magnets. The resulting force is capable of moving an object without making physical contact. This force generates a linear motion when using a flatbed track of magnets and a rotary motion when using a curled-up ring of magnets (Figure 3). The applications may be different but the technology is exactly the same.

It was mentioned before that to get the desired motion, the coils (each called a pole) need to change their polarity and strength relative to the magnets to maximize the force delivered. The standard nowadays is for there to be three different coil behaviors, called phases, acting upon the magnets at the same time (Figure 4). For this reason, the type of motors using this method are called 3-phase synchronous motors. All that a motor has as an input when it comes to performance are three wires for current and, for this reason, motors do not have any compatibility issues with different controllers.

Once the working principal is understood, it is easier to see the benefits of this technology. One of the advantages is the large force density it brings. With the motor having only two parts — the magnets and coils, they are incredibly compact for the power they deliver. The small moving carriage of a linear motor and the large hallow shaft of a torque motor allow the payload to be mounted directly to the motor, ensuring making the most of the space within the machine. This also delivers a high mechanical stiffness and allows for a greater dynamic range of motion since the forces are not being transferred through multiple parts, which also eliminates backlash and inertia mismatch.

This result is a force transmission method that can perform over a wide range of force and speed without having to make mechanical adjustments, and whose performance and precision is only limited by the feedback device to which it is attached. With these types of benefits, one may wonder why it is not more widely adopted. The reason mostly revolves around upfront price and complexity of integration. Because of cost of material, mostly the permanent magnets, there is a hesitation towards making the investment to switch over.

Along with that, when someone is already familiar with a gearbox or ball screw solution, its familiarity can be comforting. Dealing with those two factors at the beginning can look very intimidating but what needs to be understood is that a lot of the value from direct drive comes from its long term use. If a machine maker is able to make the most of its performance, they are able to greatly increase the throughput of the machine and not have the cycle interrupted with a machine down due to maintenance and part failures. When properly integrated, the user has has a motor that could be operating 10 years down the line and will perform just as well as one that is newly installed.

Every year, more machine makers are seeing the benefits of direct drive but to get the most out of them, it is important to understand their limitations as well. The concept of the force transmission being coupled directly to the payload is similar to the concept of semi-closed loop when it comes to encoders. The idea being that the less “degrees of separation” between the part, the greater will be the overall performance. If the reader imagines the different components as parts of the human body: the controller as the brain, encoders as the nervous system and the motor as the muscle. You can have one of the strongest muscles out there but if the signal to it is muddled or cut off, then you are not going to get the proper movements. Like the human body, if you are not careful, the user can run the risk of overexerting and damaging a motor.

Most of the time, a motor’s performance is limited by how much force/torque a motor can output without overheating. The better this is controlled, the more performance is available from a particular model.

Take a look at the continuous value of the motor (Continuous Force with linear and Torque with rotary); this is an average value a motor can run at 24/7. This value is the most malleable since it is very dependent of how the motor is able to dissipate heat. If the motor has some type of heat sink or is liquid cooled, there is a noticeable increase in performance, sometimes even doubled with liquid cooling due to how much heat is dissipated. Getting the exact values are realistically a matter of trial and error but pay attention to any guidelines given on a datasheet for what is being taken into account.

A motor is able to perform well above the continuous value up until the peak value. The motor is physically unable to go higher than this value typically because it is the point where so much current is added to the coils, the user runs the risk of demagnetizing the magnets. Although not as flexible as the continuous value, the time a motor can reach the peak varies from as long as two seconds to tens of milliseconds so be sure to get an idea of the length of time if it is a point hoped to reach. If heat generation is thought of as the integral of the force value, this should give you an idea of how it all comes together.

Speed is one more value that can vary the performance. Going back to the basic concept of magnets and coils, when the magnets move past the copper coils, a current is created within the copper and creates a Back-Electromotive force (or back-EMF) Voltage. To compensate, the controller has to input more current to counteract this current normally used to give the motor its power. The result is that the greater the speed at which the motor operates, the more difficulty it will have reaching similar Cemented Carbide Inserts force values than if it were operating at lower speeds. The greater the surface area between the magnets and coils, the greater the Back-EMF which is why a motor has lower speed capabilities as it gets larger or has more poles. Although this is not the only property that affects this (Eddie currents can occur and heat up parts of the motor), it is what affects it the most. Figure 5 shows how all these factors affect speed in a TMB+ torque motor (0210-07-TA2SP).

Direct drive is a very advanced piece of technology, to the point where each one of the concepts mentioned previously can be developed into its own article. The point here is to understand what this technology is, what the benefits are that machine makers can take advantage of, and the meaning behind the most important parameters.

From there one can expand their knowledge of key direct drive principles to VCMT Insert be as efficient as possible but, at the very least, one could start with a framework to develop an understanding. From there, it is a matter of deciding the value of investment that direct drive can offer for a new machine design. Different companies have different levels of investment into direct drive technology and, in the case of ETEL, it has been the focus since the inception. From Machine Tool, to Aerospace to Semiconductor Manufacturing, direct drive has increased the quality of manufactured products in many industries. As the standard of quality increases, the machines will need to adapt to the newest and best technology and direct drive is a prime example of how this can be achieved with a method that promises to be here for years to come.

American National Carbide has improved its grades designed for machining steels across the ISO P classification, from finishing to heavy roughing. All three negative-rake turning inserts in the P series have been reformulated to improve cutting characteristics and performance.

Grade AN3015 for finishing applications features a hard alloyed gradient substrate along with a multi-layered aluminum oxide CVD coating, enabling machining at higher speeds with resistance to flank wear and plastic deformation.

Cermet Inserts General-purpose grade AN3025 for machining alloy steels features a multi-layered oxide coating over a cobalt-enriched substrate for wear resistance Cemented Carbide Inserts and toughness at higher speeds.

Grade AN3035 for roughing is now more robust with a higher binder content and cobalt-enriched alloyed substrate. A multi-layered aluminum oxide coating provides toughness required for machining in unfavorable conditions, such as scale and interruptions, and with heavy depths of cut.

Walter introduces the TC388 and TC389 Supreme solid-carbide taps for threading hardened steel. According to Walter, the tools are designed to solve problems in blind-hole machining in particular, because reversing the tap during this process can cause torque peaks when the root of the chip is sheared off, resulting in tool failures.

Walter aims to solve this problem with the TC388 Supreme (50-58 RC) and TC389 Supreme (55-65 RC) with its new patent-pending cutting geometries that fully shear off the root of the chip when reversing, thus minimizing torque peaks. This prevents fractures, prolongs the tool life and increases process reliability. Furthermore, the new taps are coated using Walter’s new HiPMS Shoulder Milling Inserts coating technology, which is said to create a better surface finish and improve thread form quality. Lubrication with oil, which was often necessary until now, is no longer required; instead, standard water-based emulsions can be used, optimizing handling and saving additional machining Cutting Tool Carbide Inserts costs. The TC388 and TC389 can be used for tapping both blind-hole and through-hole threads up to 2 × DN.

The Star NTG-4L tool and cutter grinder from Star SU is a five-axis CNC grinder for manufacturing, sharpening and reconditioning a variety of cutting tools. Equipped with a four-station wheel-pack changer and Numroto software, the machine is designed for high productivity and precision. A mineral cast base provides Cutting Carbide Inserts increased vibration damping and Thread Cutting Insert thermal stability performance, and all three axes are driven by linear motors to avoid elasticity, backlash, friction effects and drive-chain vibration. Both of the machine’s rotary axes feature integrated torque motors for high and precise torques at optimal speeds, the company says. The tool and cutter grinder can be optionally equipped with an automation package including a FANUC LR Mate robot. According to Star SU, the machine’s quick setup and stability make it well-suited for high-mix, low-volume jobs.

One of the most thrilling aspects of my job has been that as I walk into our plant each day, I have no idea what problem or challenge will be put before me. Some are mundane, some are impossibly difficult. There are often many different solutions to every problem — some are better than others, but in most cases there is no absolutely correct answer. In thinking about this idea, I wanted to share a situation in which Indexable Threading Insert we were faced with a challenge and needed to think outside the box to come up with the best solution.

A good customer came to us with a new opportunity: We needed to drill and countersink four holes in a custom-shaped aluminum extrusion. The extrusions would be supplied to us cut to 6-, 8- and 11-inch lengths, having been deburred on both ends. Annual quantity would be approximately 500,000 pieces. Staub Precision Machine may be a high-end production manufacturer with some of the latest automation equipment, multi-axis lathes, four-axis HMCs and five-axis machines processing sophisticated parts; but initially, we could not find a way to meet the output requirements while meeting cost requirements.

We are excellent with aluminum, and our HMCs would eat this job up. Our normal plan of attack would DNMG Insert be to put as many parts as possible on a tombstone and drill away. A tombstone with 64 parts would be done in a flash — we estimated 8 ½ minutes. The load/unload cycle time of each tombstone would be 12 minutes. That is fast, but even with two tombstones, the machine would sit for at least 3 ½ minutes between cycles, and it would require 31 cycles to reach our goal of 2,000 pieces per day.

We would need to be flexible. It was clear to me that our normal approach wasn’t going to work. Because our roots are as a production machine shop, we tend first to look at parts from an automated CNC machining standpoint. Flexible manufacturing systems, pallets, tombstones and robots are typical tools that we pair with our CNC mills and lathes, but they wouldn’t help us with this problem. We decided that this challenge needed a custom solution, and we went down a path that was different from our typical processes.

Our team decided to design and build a special drilling machine. We mounted four electrically driven spindles on a moving slide and drove them with a servo motor. We used a variety of air cylinders to locate and securely clamp the part, paying particular attention to the datums. We used a programmable logic controller (PLC) to control the clamps and the drilling process. We used minimum-quantity lubrication (MQL) on combined drill and countersink tools. Using this method, we were able to bring our cycle time down to 6 seconds per part, and over time we were able to reach 4,000 pieces per day (twice our requirement). That put us in control of our schedule, freed up a horizontal machining center and eliminated the need for pallets, tombstones and machine time. 

In addition to drilling, the customer asked us to look at cutting and deburring the blanks. The only way it made sense for us was to cut, deburr and present the blanks automatically to the drilling operator. Our approach was to marry a cold saw and an automatic deburring station to the drilling machine. We purchased a high-end automatic cold saw and developed an automatic deburring station. After a precise saw cut, we use a conveyor to transport the extrusions to the deburring station. The part is clamped in non-marring jaws as it is moved back and forth past a set of cup-type brushes filled with highly abrasive nylon. The part is then released onto another conveyor where it is picked up by an operator and placed in the drilling operation. Cutting, deburring and delivery happen during the drilling cycle, so the operator has enough time to drill, inspect and box the hinges.

A simple challenge led us to a very unique manufacturing process. One takeaway is that not every job needs sophisticated and expensive CNC equipment. If we tried to apply our typical tools and processes to every problem, we would be missing plenty of viable opportunities with good customers. This project reminded us that we can be most successful by thinking about our problems with an open mind. We really tried to put this job on an HMC, but were more successful taking a different approach. We know how valuable our CNC machines are and how we have come to depend on them daily. But we were again reminded that they are not always the answer to our challenges.