The introduction of precision and high-performance moulds has led to ever-increasing demands on mould manufacturers in recent years. Since the precision of the shape is determined by the dimensional accuracy of the electrode, it is essential to carry out accurate measurements of the size and shape of the electrode before processing the shape. Article by WENZEL.
The LHF 2517 is a large portal measuring instrument of gantry and bridge construction for medium and large workpieces. (Courtesy of WENZEL)
Changyuan Technology (Tianjin) Co. Ltd (CHYUAN) specialises in the development and manufacture of automotive injection moulds. With a planned production capacity of 450 million moulds, the company aims to develop into one of the largest single manufacturers of automotive injection moulds in northern China.
For increased efficient production of precision moulds, CHYUAN has commissioned an automated production line for electrodes and mould inserts, which enables the integration of electrode disassembly, processing, inspection, repair and offline processes. Since the measuring system used is the key to quality assurance, CHYUAN prefers the use of coordinate measuring machines (CMMs).
A CMM provides one of the most effective solutions for measuring and collecting dimension data. First, it can replace a variety of surface-to-surface measurement tools and expensive combined gauges. Secondly, the CMM can reduce the time required for complex measurements from hours to minutes. Thirdly, it guarantees both the efficiency and accuracy of measurement of size, shape and positional tolerance of the electrode.
Automated Measurements in the Direct Production Environment
CHYUAN relies on the WENZEL coordinate measuring devices XOrbit77 and LHF 2517. The figures represent the measuring volume in the X and Z axes of 700 mm x 700 mm and 2500 mm x 1700 mm, respectively. The XOrbit was seamlessly integrated into the production line for electrodes and mould inserts for automated 3D coordinate measurement in 2019. The CNC measuring device is ideally suited for the shopfloor environment and can be equipped with switching measuring and optical sensors. The XOrbit offers excellent value for money with high mechanical precision and low operating costs.
Meanwhile, the LHF 2517 is a large measuring instrument in gantry and bridge construction for medium and large workpieces. The floor-level design of the LHF allows easy assembly with large parts with high freedom of movement for the user. The double drive in the Y-axis of the LHF ensures high measuring speeds and excellent stability of the guides.
Here’s how to bring out the best of a machine in any machining scenario while efficiently meeting workpiece accuracy requirements. Article by Heidenhain.
The Dynamic Precision package of functions for the TNC controls perfectly combines a high level of accuracy with dynamic motions.
In tool and mould making, dimensional and contour errors need to be so low as to be barely measurable and must certainly never be visible. These requirements are increasingly at odds with demands for higher productivity and lower costs.
Here are some common user questions when it comes to getting the most out of a milling machine, and how Heidenhain’s TNC technology can help solve those issues.
How can I optimally tune my machine to the given machining conditions?
In Cycle 32 Tolerance, the TNC user can precisely tune the machine setup by adapting the contouring deviation T to the task at hand, thus individually specifying the path width that is available to the control. The user can so directly influence the maximum attainable contouring feed rate, and therefore also the machining time, in particular for contour elements with numerous changes in direction—a common characteristic of free-form surfaces.
Some machine tool builders also offer their own cycles based on Cycle 32. These are often designated Cycle 332. In addition to the contouring deviation T that the TNC user enters, these cycles make further modifications to the machine setup that the OEM had programmed for specific machining operations, such as roughing, finishing, or pre-finishing.
The Advanced Dynamic Prediction (ADP) function offers another possibility for optimizing the machining process. It starts with the data quality of the NC program and enables optimized motion control for feed axes in three- and five-axis milling. An insufficient quality of data frequently causes poor motion control, leading to inferior surface quality of the milled workpieces.
With ADP, the TNC control can dynamically calculate the contour in advance and adapt the axis speeds in time for contour transitions using acceleration-limited and jerk-smoothing motion control. As a result, clean surfaces can be milled in short machining times even for contours with highly irregular point distributions in neighbouring tool paths. The strengths of ADP are apparent, for example, in the resulting symmetrical feed behaviour on forward and reverse paths during bidirectional finish milling and in the form of particularly smooth feed-rate curves on parallel milling paths.
KinematicsOpt and 3D-ToolComp make it possible to efficiently create a highly accurate workpiece using the true accuracy of the machine and tool.
How can I take full advantage of a milling machine’s dynamics?
The Dynamic Precision package of functions for the TNC controls is a collection of functions that combine high accuracies with dynamic motions. These functions minimize not only forces that affect the mechanics of a machine tool during operation, but also the resulting deviations at the tool center point.
The Cross Talk Compensation (CTC) function compensates for forces that are introduced by dynamic acceleration processes and that briefly deform parts of the machine, leading to deviations at the tool center point. Regardless of the actual acceleration, CTC makes either more precise production with better surfaces possible, or it significantly reduces the machining times by increasing the jerk.
Active Vibration Damping (AVD) suppresses dominant low-frequency vibrations and permits fast, vibration-free milling. This makes it possible to set high jerk values. Machining times can be reduced without compromising surface quality. In particular, the combination of CTC and AVD helps reconcile the contradictory requirements of accuracy and speed. In practice, this functionality provides greater efficiency during the milling of high-quality, free-form contours.
The Load Adaptive Control (LAC) function continuously determines the current mass for linear axes, or the mass moment of inertia for rotary axes, and adapts the feed-rate control to the values measured at any given time. This improves the dynamic accuracy of the axis for every situation under load, enabling the use of optimized jerk values for the feed axes on the workpiece side. The result is a shorter machining time, since the feed axes reach the desired positions sooner. In addition, LAC compensates for all changed friction values and therefore ensures higher contour accuracy.
Batch Process Manager and StateMonitor from HEIDENHAIN make process monitoring and automation easy.
How can I implement the accuracy requirements of a workpiece efficiently?
Accuracy requirements are becoming ever more stringent, particularly in the realm of 5-axis machining. Complex parts must be manufactured with both precision and reproducible accuracy, including over extended periods of time. During machining, however, machine components are subjected to relatively high temperature fluctuations. The kinematic transformation chain should therefore be adapted correspondingly. The KinematicsOpt software option not only handles the recalibration, but also saves all data regarding modifications to the kinematic configuration.
A triggering 3-D touch probe is used to measure the position of a precise calibration sphere at various rotary axis settings. The result is a report providing the current actual accuracy during tilting. If desired, KinematicsOpt also automatically optimizes the measured axes simultaneously, and requisite modifications to the machine data are also automatically implemented. The user needs no detailed knowledge about the kinematic configuration of the machine and can recalibrate his milling machine in just a few minutes. If the calibration sphere is permanently mounted on the machine table, then this procedure can even be performed as an automated step between the individual machining processes.
Radius cutters whose geometry deviates from the ideal circular shape also negatively affect the machining result, since the contact point of the cutter radius with the workpiece as calculated by the control does not match the value for that of the actual radius.
The 3D-ToolComp option and touch probe Cycle 444 together are a powerful method for three-dimensional tool radius compensation. A compensation table enables the specification of angle-dependent delta values that describe this deviation. The TNC control uses this data to compensate for the radius value defined at the current tool contact point on the workpiece.
For the contact point to be determined with precision, the NC program must be generated with surface-normal blocks (LN blocks) by the CAM system. These surface-normal blocks define the tool position and the contact point on the workpiece, and optionally specify the tool orientation relative to the workpiece surface.
How can I plan and monitor automated production with ease?
If the machine tool provides perfect machining results, then the associated processes should also run in an optimized manner. Intelligently networked systems for job planning, job management, and job monitoring should provide a comprehensive view of job lists, running processes, work progress, and any necessary interventions.
Batch Process Manager organizes pending jobs clearly and in a logical manner. To accomplish this, the user creates a lineup of jobs directly on the Heidenhain control. These might be jobs for the approaching night shift, for an entire day, or for the upcoming weekend. Batch Process Manager checks this job list and provides important information prior to machining, such as when manual interventions will be necessary and how long the machine will be utilized. Batch Process Manager thereby allows for precise planning of the machining sequence and facilitates the smooth execution of pending jobs.
The StateMonitor software gives a fast, real-time overview of the current machine and job statuses for all connected machines. This monitoring software enables machine data acquisition (MDA) and provides information about machine messages. The user thereby maintains an overview of his machine tools and jobs at all times. The user can access StateMonitor from any device featuring an up-to-date web browser, meaning not only PCs, smartphones, and tablets but also, of course, controls from Heidenhain and Extended Workspace.
Many powerful TNC functions of Heidenhain controls offer possible solutions to the key questions that arise between the conflicting demands of a production process that is highly precise and at the same time highly efficient. The user can take advantage of these functions that bring out the best of a machine in any machining scenario while efficiently meeting workpiece accuracy requirements.
There are plenty of potential benefits in making good use of standardisation concepts when sourcing a mould base. Article by Lung Kee Group (LKM).
Injection moulding is one of the key processes in today’s manufacturing industry, enabling manufacturers to achieve economy of scale in production of high-volume plastic or metal parts. The quality of the mould, usually defined by its precision and overall reliability, plays a critical role in determining the success of the final product.
In very simple terms, a mould base is a semi-finished mould. The basic structure of a mould base consists of several drilled or machined mould plates assembled together with mould components. Modern mould makers tend to purchase mould bases from specialist mould base suppliers, in order to reduce overall manufacturing time and the costs associated with machinery and raw material investments. Perhaps most importantly, using a mould base enables the mould maker to focus on the high value-adding portions of the mould manufacturing process, such as design, polishing and final production tests.
Just like many industrial processes, there are plenty of potential benefits in making good use of standardisation concepts when sourcing a mould base. The most obvious one is cost, as standard mould bases can be ordered from catalogue, offering good price transparency. The leading suppliers in Japan, Europe and Asia all have highly engineered production lines to achieve a high level of machining precision on a consistent basis—so, by making use of their standard products, mould makers can also enjoy the economy of scale in terms of competitive pricing. Standardisation also helps mould makers’ internal workflow by speeding up the design process. In fact, many CAD packages contain libraries of common mould base standards.
A good standard mould base has three defining qualities: reliable material, reliable precision, and reliable availability. The importance of raw materials should not be underestimated, as moulds made with poor materials risk plate deformation or even fracture due to metal fatigue. Reliable precision is quite often easier said than done, as the quality from small scale manufacturer tends to highly depend on individual workmanship.
And of course, good quality products mean nothing if one cannot buy them easily. Leading mould base suppliers tend to have superior financial strength to invest in good material procurement capabilities, strong CNC machine portfolio and large inventory, and above all, they tend to have a commitment to high quality.
LKM Discusses Benefits of Standard Mould Bases for Vietnam Manufacturers
Established in 1975, Lung Kee Group (LKM) is one of the leading mould base manufacturers worldwide. The company is headquartered in Hong Kong, with product lines ranging from standard and custom-made mould bases, to precision machining and mould components. LKM is also a distributor of quality tool steel brands such as Japanese Daido, Assab Uddeholm, Arcelormittal, Bao Steel, and its own brand ‘LKM Special Steel’.
For the past 40 years, LKM is instrumental in the growth of the mould making industry in Asia. Through commitments to quality and integrity, and a relentless drive to excellence, LKM has developed from its modest beginning into an industry leading powerhouse in mould base manufacturing. In fact, LKM was the first Hong Kong company to introduce CNC machining centres for mould base manufacturing. LKM’s reputation as an industry leader in the mould base industry was further solidified through its listing on the Hong Kong Stock Exchange in 1993.
At present, LKM manufactures over 55,000 complete sets of mould bases per month. In term of custom-made mould base, the company has world-class machining capacity, powered by a team of engineers and machine operators with over 30 years of combined experience in making complex custom-made mould base for the automotive industry and precision machinery.
In an interview with Asia Pacific Metalworking Equipment News (APMEN), Cyrus Lau, assistant manager of Lung Kee Metal Japan Co. Ltd (HCMC Office)—LKM’s Vietnam office—talks about Vietnam’s mould & die industry and what’s driving growth in the market.
Q: How would you describe Vietnam’s mould and die industry?
Cyrus Lau: Vietnam is one of the biggest centres of manufacturing industry in Southeast Asia. Its mould & die market is comprehensive, ranging from sheet metal dies, die casting dies, and forging dies, to jigs, fixtures, gauges, and more. Key factors driving the market include the growing support from Japanese moulding companies. Overall, there is a large number of local manufacturers, suppliers, and distributors operating in Vietnam’s mould and die industry.
Q: How does LKM position itself in the Vietnam mould & die market?
CL: We are a mould base manufacturer and machinery specialist. We don’t think any company in our industry can claim to produce over 100 tonnes of metal chips like we do! But most importantly, our LKM standard is known to be very reliable, and is one of the most popular mould base brand in the world. When customers buy LKM, they know they get good and reliable quality. We have a large number of Japan-made machining centres, and we can cut over 100 tons of steel materials a day. In addition, we work with customers and provide them with materials and processing advice.
Q: How are you helping your customers address their manufacturing challenges?
CL: For Vietnamese mould makers, reliable quality and speed are very important—and the easiest way to improve this is by adopting standardisation in mould bases. This will improve lead time, quality, and make mould designs easier. Of course, standard products also tend to be cost efficient, which is clearly beneficial for mould makers.
At the EMO 2019 Agathon will highlight new developments in the field of machinery and services, as well as solutions and innovations for guiding, centering and quick-change, especially for tool and mould making.
Agathon will be presenting its broad portfolio for tool and machine construction to visitors at the EMO 2019. The company highlights their top products such as the roller guide systems, in particular, for tool and mould making, but also for mechanical engineering and automation.
This porfolio also includes the Mini Fine Centering, which has gained an excellent reputation since its market introduction in the spring of 2018. With the static application of the Mini Fine Centering tool and mould inserts can be backlash-free, easy rolling and thus highly precise centered and they can also be changed extremely fast, without expert knowledge and without tilting.
Mechanical engineers are increasingly enjoying the opportunities for quick change, which is offered by the mini-fine centering. A popular field of application is the quick exchange of clamping tools. Other areas of application for the Mini Fine Centering include precision automation, for example, when gripper tools are positioned. There, the Mini Fine Centering ensures maximum process reliability, it eliminates vibrations and guarantees gentle and precise part removal.
The Mini Fine Centering can now also be used for dynamic applications. In particular, the centering of floating cavities in multi-cavity tools and moulds should offer a broad field of application for the Mini Fine Centering. Thanks to its small footprint, the number of cavities can be increased by up to 30 percent. Since the Mini Fine Centering is not paired, additional bushings of the standard 7989 can be used – in particular for turning tools or automation solutions, this offers new application possibilities.
Furthermore, the new maintenance-free sliding bushing is Agathon’s third spring innovation. It distinguishes itself especially for dry running, whereby the small backlash enables a very precise guidance. The sliding surface of the bushing is designed and structured to achieve a very high performance together with the surface of the pillars, the counter partner from the Agathon range.
Tungaloy Boosts Deep Hole Drilling Productivity has expanded its Tungaloy DeepTriDrill line of indexable gun drills to include new drill diameters ranging from ø12mm to ø13.5mm. With new drill sizes in the lineup, Tungaloy DeepTriDrill can now address the diverse deep hole drilling needs of automotive and mould set parts for maximum efficiency and stability.
In addition, the drill diameter can easily be altered in increments of 0.01mm to the required hole sizes simply by placing dedicated adjusting shims beneath the guide pads, allowing an overall reduction of cycle time and manufacturing costs in diverse deep drilling applications. The H-class insert features unique cutting edge configuration that provides hole accuracy at greater feed rates, while also ensuring smooth chip evacuation.
The expanded line includes 12 drill bodies and one insert.