By the very nature of their business, contract machining shops are constantly looking for ways to sharpen their capabilities and reduce costs to quote jobs more competitively. Price, along with quality and delivery, can contribute to a winning recipe.
Southern California’s Fontal Controls is one example of a shop that constantly searches for new ways to maintain a competitive advantage in a crowded field. With this mindset, the shop set an agenda calling for the capability to cut steel as hard as 47/48 Rc quicker and more effectively. In addition, the company says it wanted to rough aluminum faster to make detailed cuts on contoured parts without stalling the tool. Also, running at higher feed rates without breaking tools would enable fewer passes, thereby further reducing part costs. Other goals included improving surface finishes, reducing tool changes and eliminating clean-up operations, all of which would require less machine vibration. A new machine would need to be rigid enough to reduce vibration and cost-effective enough to justify the shop’s investment.
With these objectives in mind, Fontal Controls acquired a VMC designed with a rigid boxway construction and equipped with an 8,000-rpm spindle. The machine, a VMC 3016FX, was designed and built by Chatsworth, California-based Fadal Machining Centers. Fontal now says its revenues have increased because of this machine’s fast cycle times.
Oscar Fontal founded the company in the early 1980s with just one machine. The company grew quickly by focusing on precision CNC machining and turning of components for the die and mold, machine tool and aerospace industries. In addition to these operations, the shop also performs grinding and other finishing work. Dimensional inspection and surface-finish inspection are carried out in-house.
In 1994, Fontal moved to a 14,000-square-foot facility in Sylmar, California, which is near Los Angeles. Today, the founder’s sons run the company as partners. Seven of the company’s 16 CNC machines are VMCs that can accommodate workpieces measuring as large as 24 by 48 inches. Of those seven VMCs, six were designed and built by Fadal.
Although the machining programs and cycle times vary, Fontal says the new VMC has increased parts-per-hour productivity by more than 40 percent compared to the previous machine. On one large, complex aluminum aerospace part, for example, spindle speed on deep profiling jumped from 5,500 rpm to 7,000 rpm. The feed rate also increased to 100 inches per minute—nearly triple the rate on the older machine.
To machine these aluminum aerospace parts, the company takes 1.260-inch-deep rough-cut passes with a 1-inch-diameter, coarse-tooth rougher. The cycle time on the rough, deep-cut operation was reduced from more than 9 minutes to approximately 6 minutes. Cutting Tool Carbide Inserts Total machining time dropped from 79 to 54 minutes. In fact, revenues on the new machine alone increased by more than 46 percent per day.
Recently, the company ran a batch of 147 of these parts without any cutter compensation. Fontal programmer and machinist Art Martinez says this is a testament to the machine’s rigidity, and he estimates that repeat batches throughout the year will yield substantial cumulative savings for the customer. Another benefit is that this capability will “open the doors” for the company to gain larger-part work.
Mr. Martinez says that Fontal has also achieved faster drilling and milling cycles on 15-5 heat-treated, 42-Rc steel, as evidenced by a recent job machining an adaptor part.
Spindle speed and rigidity are the two biggest attributes that persuaded Fontal to purchase the 3016FX. Carbide Drilling Inserts The machine’s cast iron, boxway construction is designed to provide large surface-area contact on the integral, flame-hardened ways. This helps maintain rigidity by damping vibration during heavy cuts. According to the manufacturer, accuracies stay high and predictable on circular features, and reversal error is virtually eliminated.
The machine features XYZ axis travels of 30 by 16 by 20 inches (762 by 407 by 508 mm). The VMC is part of a family of three Fadal models. These include the 2216FX, which features a smaller envelope, and the 4020FX, which has axis travels of 40 by 20 by 20 inches (1,106 by 508 by 508 mm).
A maximum deviation of 0.000232-inch roundness has been verified with a standard ballbar test (ASME B5.54), the company says. Accuracy is also enhanced by increased stiffness resulting in part from the Steinmeyer ETA+ dual-mounted ballscrews. Fontal says its part programmers and machinists are receptive to the Fadal GE Fanuc Oi-MC control because they are already familiar with the Fanuc controls on other machines in the shop. The company also cites an intuitive interface and expanded functions as factors in simplifying part setups. In addition, the machine is equipped with a 21-tool ATC, which is suited to Fontal’s type of work.
“The rigidity of the Fadal machine is important to our part finishes,” says Cristian Fontal, managing partner and controller. “The ballscrews are fast and offer accuracy. The machine affords us the versatility to cut both steel and aluminum quickly and accurately.”
Manufactured by Kaiser Tool Company, Thinbit’s Groove ‘N Turn inserts are designed to both groove and turn using narrow insert widths. They are useful for manufacturing medical components such as stents, bone screws, implants and surgical gun drilling insertsgun drilling inserts tools. Geometries and grade can be tailored for titanium, plastics and BTA deep hole drilling inserts stainless steel.
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The company’s offset insert design allows grooving or turning up to a shoulder. Insert geometries are available for grooving, threading, face grooving, parting and special configurations. The inserts are available in groove width sizes ranging from 0.004" to 0.150" in 0.001" increments with either sharp corners or 0.007" radius. The come in two sub-micron grain carbide grades: DM-2 for steel and interrupted cutting and DM-5 for aluminum and other non-ferrous alloys. High speed steel as well as TiN, TiCN, TiAlN and diamond coatings also are available.
While machining 2,000 bushings for a hydraulic pump used in the aerospace industry, Kyle Hawley, owner of L.A.Y. Precision Machine, recognized that the CCMT-type carbide cutting tool insert that the shop was using to bore the hole was causing three specific problems:
Mr. Hawley’s cutting tool supplier put him in touch with an application and sales engineer at Horn USA, who recommended the Supermini 105 tool system with an HS36-grade boring bar insert. The inserts BTA deep hole drilling inserts have a carbide substrate, a high-temperature-resistant coating and an adapted cutting-edge geometry specifically designed for hard turning materials ranging to 66 HRC, eliminating the need for cubic boron nitride.
According to Mr. Hawley, the results achieved with the new cutting Carbide Milling Inserts tool exceeded his expectations. Cycle time was reduced from 8 minutes, 5 seconds to 1 minute, 23 seconds, and each boring bar now can be used for 75 parts. In addition, surface finish Ra improved to 20 microinches. Mr. Hawley says that the boring bar can be changed out quickly, which is an additional benefit. All of this adds up to a 78 percent reduction in manufacturing cost.
1. The contradictory characteristics of traditional uniform carbideCemented carbide is a typical brittle material. The traditional uniform carbide one, the material of the various parts of the uniform composition and organization, the alloy is homogeneous throughout, its performance is consistent. The main components of cemented carbide include various hard phases and binding phases. Hard phases such as phases and solid solutions play an important role in the hardness and wear resistance of alloys. Bonding has an important influence on the strength and toughness of alloys.In general, increasing the WC grain size or increasing the Co content will increase the bond phase thickness of the alloy and improve the alloy plasticity. In alloys with good ductility, local concentrated stresses can relax the alloys with poor plasticity due to deformation. Crack initiation and propagation are induced by stress relaxation, resulting in cracking of the alloy.Therefore, the traditional method is to increase the alloy. The content and increasing the grain size serve as a direction to increase the toughness of the hard alloy. However, at the same time, the hardness and wear resistance are reduced. Conversely, hardness and wear resistance can be increased without sacrificing flexural strength and impact toughness. Therefore, there is a sharp contradiction between the hardness and toughness of cemented carbide materials, and it is not easy to obtain a conventional uniform cemented carbide with high hardness and toughness at the same time. In many service conditions, the application of traditional uniform hard alloys will have certain limitations. For example, when the rock drill ball and the cobalt head are working, they are not only subjected to impact load and torsional load, but also have to be seriously worn by the rock.This requires that the cobalt teeth not only have sufficient impact toughness, but also have high The wear resistance can complete its work. When used in synthetic diamond synthesis, carbide top hammers are subjected to high temperature and high pressure, some parts are subjected to compressive stress, and some parts are subjected to tensile stress or shear stress. Different parts have requirements.Different performance and features. In this way, the conflict between the hardness and toughness of the traditional uniform structure hard alloy restricts the further expansion of its application field, it is difficult to meet the "double high" high hardness and high toughness requirements for the development of modern society, so explore The new type of hard alloy material makes it particularly important that different parts of the tool have different functional requirements.2. New advances in cemented carbideThe materials scientists of various countries in the world are trying to solve the above-mentioned contradictions in the traditional uniform hard alloy through various effective ways, reduce production and use costs, and improve their comprehensive performance. At present, there are mainly ultra-fine and nano-hard alloys (so-called ultra-fine cemented carbide is an alloy with a tungsten carbide grain size of 0.2-0.5 μm, and nano-hard alloy is an alloy with a tungsten carbide grain size of less than 0.2 μm. ), platelet toughened carbide, coated carbide and functional gradient carbide, and other directions can effectively solve this contradiction. For example, when the cobalt content of the nano-size hard alloy is high, not only has good fracture performance, but also has a high hardness, reaching the best combination of alloy toughness and hardness functional gradient carbide by making the binder phase or hard phase along One direction is increasing or decreasing to give the different parts of the alloy different properties, so that the combination of toughness and wear resistance can be fully achieved in the use of the carbide. The following is a brief introduction to the new progress of gradient cemented carbide.Functionally Graded Cemented Carbide3. Gradient carbide proposedAbrupt changes in material composition and properties in the component often lead to significant local stress concentrations, whether the stress is internal or external. If the transition from one material to another is performed gradually, these stress concentrations will greatly increase. reduce.These considerations form the basic logical element of most functionally graded materials. Japanese scientists first proposed functionally graded materials, which are characterized by the introduction of gradual changes in the microstructure and/or composition of a component, the gradual change of its microstructure and/or composition in space, and the physical, chemical and mechanical properties of the material.The performance exhibits a corresponding gradient change in space, so that it meets different performance requirements at different locations in the component, thereby making the component as a whole achieve the best results.This design idea was introduced in the field of cemented carbide in the mid-to-late 1980s, and a gradient cemented carbide was proposed, and rapid development was quickly achieved. In the actual use of cemented carbide, different working sites often have different performance requirements. For example, the cemented carbide cobalt head requires high surface wear resistance and overall impact resistance.It is conceivable that if a new type of cemented carbide material can be developed, the structural feature of this material is that the surface layer is a structure with a low binder phase and the binder phase content of the core is an average value, between the surface layer and the core. It is a transition layer with a high binding content and a continuous distribution. In this kind of structure, due to the different distribution of bonding phase in each part, the content of the bonding layer in the alloy surface is lower than the average value in each part, with high hardness and good wear resistance, and the binding layer content in the transition layer. High, can meet good toughness and impact resistance.4. Properties of gradient cemented carbideIn the two-phase structure, the cobalt content of the surface layer is lower than the nominal cobalt content of the alloy, the cobalt content of the intermediate layer is higher than the nominal cobalt content of the alloy, and the cobalt content of the core containing the η phase is the nominal cobalt content of the alloy. As the cobalt content of the alloy shows a gradient change, the hardness of the different parts of the alloy also reflects the corresponding laws. Moreover, the gradient distribution of cobalt content makes the sintering shrinkage in different parts of the cross section non-uniform, resulting in residual stress in the alloy. Due to the low content of cobalt in the surface layer of the alloy and the high content of WC+Co+η, the surface of the alloy has very high hardness and very good wear resistance. In the middle layer of the alloy, the cobalt content is higher than the nominal content of the alloy, and thus The layer has good toughness and plasticity, so that the alloy can withstand higher loads. The η phase structure inside the alloy has good rigidity. The experimental results show that the wear resistance and toughness of DP alloy are obviously better than that of the traditional uniform hard alloy. The adoption of DP alloy can obviously improve the efficiency of rock drilling and reduce the mining cost.According to the current research status of gradient materials in various countries, there are mainly three types of gradient cemented carbide bonded phase composition carbides such as alloys, hard phase composition gradient cemented carbide (such as the β-layer used as a coating matrix. Gradient cemented carbide) and hard phase grain size gradient cemented carbide (such as grain-gradient cemented carbide top hammer).5. Gradient formation mechanismThe viewpoint of the formation mechanism of the gradient distribution of the cobalt phase caused by the directional migration of the liquid binder phase in the alloy after carburizing has not yet been unified. According to current research reports, the directional migration of liquid phase mainly includes mass migration caused by three different Carbide Milling Inserts types of liquid phases, orientational migration of binder phase caused by different WC particle sizes, and liquid phase migration caused by different carbon content. For example, two YG alloys with the same WC carbon content, uniform particle size, and different binder cobalt content are overlapped and held at the liquid phase temperature for a certain period of time. As a result, the bound cobalt phase shifts from a high cobalt content to a low cobalt content. One side of the migration,.For example, one of different particle sizes is fine particles, and the other is coarse particles added with the same cobalt to form two kinds of mixture, and pressed into a double-layer alloy for vacuum sintering. The liquid binding phase appears to be fine from one side to the other. The grain side migrates. While the high carbon cemented gravity turning inserts carbide is decarburized in the decarburizing atmosphere, the liquid binding phase will migrate from the inside to the surface of the sample, while the low carbon alloy will migrate to the center after the carburizing treatment liquid binding phase.The phenomenon of migration caused by the difference in carbon content is caused by the difference in the amount of liquid phase in the different parts of the alloy. This type of decarburized or carburized alloy has an unequal internal carbon content, and the carbon content is relatively high in regions with high carbon content. In regions with lower carbon content, the liquid phase migrates from areas with high carbon content to areas with low carbon content. Taken together, the main mechanisms of liquid phase migration are:The binder phase migrates from the coarse-grained carbide region to the fine-grained carbide region, and the driving force for the migration is the capillary pressure difference, that is, the action of the capillary force. The binding phase migrates from the high liquid phase region to the low liquid phase region and migrates. The driving force is the pressure difference in the liquid phase, that is, the role of volume expansion or contraction to generate pressure when the state of the substance in the liquid phase volume difference changes.6. Application of Gradient Cemented CarbideGradient cemented carbide successfully solves the contradiction between hardness and toughness existing in conventional homogeneous cemented carbide. The development of this new material is considered to be the most important one in the history of cemented carbide since the 1950s. Innovation." Due to the unique microstructure and properties of gradient cemented carbide, it has become an important research content in the field of gradient functional materials and hard alloys. Currently, it has been widely used in coating substrates, carbide cutting tools, mining and rock drilling tools, stretching dies and punching tools, and its application fields are constantly expanding.(1) Used as a coating substrateDue to the different thermal expansion coefficients of different materials, coating tool materials may crack due to thermal stress during cooling. Gradient structure cemented carbide is used as the matrix, that is, the gradient-sintered coating matrix forms a ductile region lacking cubic carbides and carbonitrides in the surface region, which can effectively prevent cracks formed in the coating from expanding into the interior of the alloy. , improve the interface bonding strength and reduce interface stress concentration, thereby improving the performance of carbide cutting tools.(2) Used as a carbide toolChange the traditional cemented carbide. The constant proportion model is used to make a graded structure hard alloy with low surface content and high core content, so that the surface layer has high hardness and good wear resistance, while the core has high strength and good impact toughness, which makes the strength and toughness of the alloy. It is well coordinated and can therefore be used to produce cutting tools with both wear resistance and toughness.(3) Mining and rock drilling tools Mining and rock drilling toolsThe use of ball teeth requires greater wear and impact during operation, which requires the alloy to have high surface wear resistance and high strength. Conventional uniform alloys are difficult to meet this requirement. Both wear resistance and toughness are significantly better than conventional uniform carbides.(4) Used as a punching toolSheet metal is usually prepared by punching or punching. With this method, the material is broken between working edges that face each other. During punching, the punch moves through the die in a direction perpendicular to the metal plate and punches the metal plate. The failure mode of the punch is usually due to the wear of the working edge and eventually leads to the cutting edge of the punch becoming conical, thereby increasing the frictional force during punching and eventually leading to a decrease in punching quality. In order to increase the life of the gradient carbide cutting tool as much as possible, a graded cemented carbide with a central η-phase region should be used, surrounded by a nucleus-free surrounding region, and with an exposed working surface of the η-phase. Using cemented carbide as the punch, the grain size of WC is 2-3μm, the number of punching times for standard cemented carbide is only 15 times, and the number of punching and shearing of cemented carbide for gradient structure is up to 64,000 times, while that of steel die punching The number is about 7231 times. It can be seen that gradient cemented carbide as a punching tool can greatly improve the service life of the tool.The study of gradient cemented carbide consists of three parts: material design, material preparation, and property evaluation. These three parts complement each other and are indispensable. Material preparation is the core of the gradient cemented carbide research. The material design provides the best composition and gradient distribution of the structure. To judge whether the designed and prepared material meets the predetermined function, performance evaluation must be performed.7. Gradient Cemented Carbide DesignGradient cemented carbide design, generally should go through the following several links First according to the structural shape of the components and the actual conditions of use, draw the thermodynamic boundary conditions from the existing material synthesis and performance database, select the possible synthesis of metal-ceramics Material combination system and preparation method Assume the combination ratio and distribution rule of the binder phase and the hard phase, and use the material microstructure mixing law to derive the equivalent physical parameters of the material structure using the thermoelastic theory and the calculation mathematics method. The distribution function of the gradient components of the material structure is simulated by temperature distribution and simulated by thermal stress, and the optimal composition distribution and material system are designed. The core work of gradient cemented carbide design consists of the following three parts:(1) Establish an appropriate gradient component distribution model so that the gradient functional material designed meets the performance requirements(2) Estimating physical properties of gradient materials(3) Calculation of temperature field and thermal stress of functionally graded materialsSee our tungsten carbide mining button bits here Source: Meeyou Carbide
Root form slots found in turbine rotors are characterized by complex contours and precise dimensions. “Christmas tree” form tools used to cut those intricate slots must be precisely ground so no portion of their profile pushes through their tight tolerance band. Consequently, setting up grinding machines to repeatedly deliver Carbide Milling Inserts quality root form tools is often challenging and time-consuming.
These setups typically involve grinding a trial tool, measuring the tool to identify the portions of the profile that are out of tolerance, and manually tweaking the machine and/or part program to compensate for grinding discrepancies. Depending on the application, this setup procedure can take hours.
The automated Form Tool Compensation (FTC) system developed by Walter (a United Grinding company) offers a more streamlined way to set up these jobs while ensuring ground profile accuracy to as little as 2 microns. By shortening, simplifying and automating the setup process, this technology minimizes turnaround time for manufacturers currently producing such complex root form tools and opens up opportunities for those hoping to enter this market.
The gravity turning inserts FTC system is available for use with the company’s Helitronic grinding machines and supports three tool grinding methods: faceted relief, cam relief and cylindrical grinding. The heart of the system is measurement/program compensation software that links the grinding machine and a tool measuring device. Tool measurement can be performed using one of the company’s standalone Helicheck scanning machines or a portable, on-machine scanning unit Walter recently introduced.
After a preliminary tool is ground to its upper tolerance, the measuring device (either a Helicheck or the on-machine scanning unit) scans the tool’s entire profile without any operator involvement. (It takes 5 minutes to scan a 60-mm profile.) The FTC software then compares the measured profile to the CAD model and automatically creates and sends compensation corrections to the grinding machine’s control. At this point, the grinding machine is ready for a production run.
When a Helicheck is used as the accompanying measuring device, FTC can deliver a ground profile accuracy within 2 microns. When the on-machine scanning unit is used, FTC is only minimally less accurate at 3 microns. However, the on-machine scanning unit can be used on multiple Helitronic machines and costs less than standalone equipment. The on-machine measuring unit consists of a high speed CCD camera coupled with a collimated LED backlight. The backlight allows the camera to reliably distinguish a tool’s cutting edge regardless of tool material or surface finish. The unit installs in the grinding machine’s head in less than one minute without calibration thanks to a self-centering interface. It uses air nozzles to automatically clean tools before performing its scanning routines. After the unit measures a tool, it is removed to allow grinding to be performed.
The on-machine FTC version is offered as an option on new Helitronic machines. It currently can’t be adapted for use with older Helitronic machines because a different grinding head design is needed to allow the head to accept the scanning unit.
