Precision Processing Requires Precision Equipment

It’s a given that precision plastics processing requires precision equipment. But, the ability to deliver precision equipment that actually provides real solutions can be a challenge. In injection molding, for example, the trend towards miniaturization in medical, electronic and micromechanical devices is driving the demand for micromolding, where, in some cases, only a handful of pellets are needed to produce a part. Similar trends are ongoing in extrusion, particularly in ultra-tight tolerance, thin-wall tubing for medical and other similar applications, where in some cases the part can be only as thick as a strand of hair.

A great example of this approach is in the micromolding market where assessing the need requires a holistic approach toward equipment selection. Ideally, the molder should look beyond the shot size and output capabilities of the injection press and extruder, and also beyond the capabilities of the tooling itself. Auxiliary equipment for these applications must be selected based on the specific end-use needs of the application.

In North America this may require a shift in the way processors evaluate their equipment needs. Many molders and extrusion processors will admit that they often purchase equipment — auxiliary units in particular — sized above their current needs in anticipation of what they might require in the future. In applications such as micromolding and precision extruders, where less than 15 pounds per hour is being fed into the systems (sometimes much less), this could result in material waste and inefficiency. This can be especially problematic in these types of demanding markets, as resin tends to be expensive and cost efficiencies and cost savings are always part of the production equation. Equipment footprint is a critical factor that must be considered as well, as more processors are moving their production systems to cells to help maximize usable space efficiently.

Moretto offers a broad suite of auxiliary solutions targeted specifically for precision processing. Whether as a standalone piece of equipment, or combined in a linear process system, across the board these devices are compact yet robust, durable yet maintenance-friendly, powerful yet energy efficient and provide the accuracy that these applications require.

Moretto’s Auxiliary Equipment Solutions

Conveying Solutions: Single-Phase Hopper Loaders and Receivers

Take conveying, for starters. An ideal resin-conveying system should maximize uptime by ensuring that waste is minimized, and maintenance is less frequent. Moretto’s KASKO single-phase hopper loaders meet these requirements in a compact and functional package.

The rugged, all-stainless-steel hoppers resist rust and corrosion. They fit easily atop processing machines, dryers and blenders. A spring-assist feature permits the lid to be opened easily, allowing safe and easy access for cleaning and maintenance. And, while filter cleaning is overlooked in many processing plants, KASKO is automatically cleaned to keep the vacuum motor and the overall loader up and running. A discharge access door provides easy inspection of discharge valve; there is no need to pull the receiver out of the blender or drying hopper. The unit is also quiet, registering less than 76 db(A). KASKO is equipped with the soft-start system and air inlet with vortex effect that significantly increases the filter’s autonomy.

CASE IN POINT: Utilizing stainless steel on loader, dryers, blenders and non-ferrous contact point in the mold temperature, you never have to worry about paint or carbon steel in your final product.

You won’t have to worry about external cables either, an important feature in molding cells, where they can be trip hazards. The control electronics are integrated in the machine through a metal profile to be protected against shocks and dust.

Moretto’s KASKO single-phase compact hopper loader.

For operations with multiple processing machines, using a centralized conveying system with low maintenance 3-phase conveying power and vacuum receivers in place of self-contained vacuum motors makes the most sense. Moretto has designed the KASKO series of receivers, powerful yet quiet 3-phase vacuum pumps and centralized dust collectors integrated with their One Wire 3 central vacuum controls, the first self-adaptive conveying system on the market based on the plant’s effective needs including the conveying distance to the receivers, the feeding time and the line cleaning time.

One Wire 3 can manage up to 80 devices including receivers, vacuum units and automated resin routing systems, called “Dolphin.” The intuitive 10-inch, object-oriented touchscreen interface is designed for the overall control of these processes inside the plant.

Drying Solutions: Efficiency, Precision in a Small Package

Micromolding applications often require use of hygroscopic materials that need to be precisely and meticulously dried. Under-drying a material will lead to splay, among other processing issues. Over-drying will tend to make parts brittle and prone to fail. Moretto has several solutions for these demanding applications, notably around its XD Mini and X Comb technologies.

The Moretto line of XD Mini Dryers has become a solution for processors around the world, with more than 15,000 units in operation at plants globally. Thanks to compact dimensions, the XD Mini Dryers can be installed directly onto the processing machine. They are suitable for drying a range of engineering resins such as nylon 6, PBT, PEEK and several materials commonly used in medical, optical, electronics and telephony. These materials are, in fact, in continuous evolution and development and require extensive treatment to ensure that the finished product meets the strict standards required.

Moretto’s Mini-Dryer range: on the left, the XD Mini TX and on the right the XD Mini XM.

The XD Mini line of twin, self-regenerating dessicant towers is based on Zeolite technology that provides a constant -62°F (-52°C) dew point. Available exclusively from Moretto, Zeolite is one of the world’s most efficient moisture absorbers. It thoroughly dries the regulated compressed air flow sent to the hopper. The airflow adjustment is automatic in the XD Mini series. Once operators set just two parameters on an advanced color touchscreen control – material type and hourly throughput – the dryer automatically manages and adjusts airflow to treat the resin with a significant energy efficiency.

Another standard feature, adaptive airflow is an antistress feature that prevents over-drying the polymer. The use of the OTX (Original Thermal eXchanger) hopper significantly enhances the performance of the drying unit, making the drying process extremely energy efficient. The OTX is a patented unit fabricated in durable stainless steel with Moretto’s elegant Spyro finish.

Moretto’s XD Mini XM series is ideal for medical and optical applications. In this design, the OTX hopper is made of clear Pyrex, so its contents are clearly visible.

CASE IN POINT: Airflow management compared to temperature setback: Moretto dryers are constantly monitoring process conditions and automatically adjusting airflow (not temperature) for that specific application giving you consistent temperature into the machine throat.

Multiple connection possibilities via USB and MODBUS serial ports enable these products to be seamlessly integrated in Moretto’s supervision and management system (MOWIS), as well as connectable to individual instruments for process data collection. Multiple versions are available for connection to a Master 300 palmtop device for improved ergonomics in multihopper applications, or in the case of on-machine installations.

Moretto is well-known around the world for its innovative approach to R&D and product development. New products and solutions are designed to simplify the production of plastic products. This makes Moretto a preferred strategic partner for high-technology applications in the medical, electronics and packaging fields. The overriding concern in these markets is for products that improve human life and enhance company competitiveness, always with the goal of achieving smart and sustainable energy use.

Another solution-oriented example is in polymers used for producing high-tech products in small dimensions and high volumes that require special care during the transformation process, beginning with the very first steps of the production cycle. External factors such as ambient temperature and moisture greatly affect the result. Therefore, a system that ensures consistency and stability is crucial to generate high quality products, while at the same time maintaining consistent product characteristics. This is where Moretto’s X Comb range dryers have found a home.

Moretto X Comb dryers are a range of super-compact dehumidifying systems that guarantee excellent resin drying performance, regardless of external ambient conditions. The all-electric dryers are ideal for advanced polymers requiring high levels of dehumidification for the technical product being produced. Outstanding performance is achieved by a honeycomb desiccant rotor with molecular sieve made of Zeolite that provides a constant -76°F (-60°C) dewpoint.

Moretto’s X COMB dryer.

Similar to the XD Mini Dryer line of mini dryers, the X Comb line also features the adaptive antistress feature that ensures a constant temperature of the polymer by avoiding thermal stress or over-drying and contributing to an intelligent use of energy, all while maintaining production performance at the highest level. The result is tailored drying performance, perfectly aligned with the needs of the resin. And most important, the X Comb series (like all Moretto dryers) align their operation with changes in consumption, so it is the polymer itself that drives the process by modifying their air volume, never changing their drying temperature.

How Variable-Flow Turbo Compressors Make a Difference

The secret to the X Comb’s precise control of drying parameters is two Moretto-developed, variable-flow turbo compressors designed to supply only the required airflow needed to optimize drying performance and keep energy consumption in check.

Comparison between a conventional hopper and OTX.

X Comb drying systems are combination hopper and dryer units, mounted to a common throat, ready to be mounted to a processing machine throat. Located adjacent to the drying hopper window is a quick reference readout of the actual process temperature within the drying hopper, plus a row of indicator lights that provide an instant recognition of normal drying operation.

The side of the dryer includes a full-color, compact touchscreen control panel where dryer settings are made and process details are displayed along with explanatory graphics. An onboard library of 100 resin parameters is provided and stored within the control, allowing users to instantly access parameters for easy programming of the dryer for operation. User-customized programs can be easily stored in the dryer for future use, as well. Dryer start-up requires operator input on a color screen only of the resin to be dried and the expected throughput. All other aspects of operation are performed automatically upon start-up, modulating dryer performance accordingly and minimizing energy consumption.

Each X Comb dryer includes a Moretto OTX drying hopper matched to the throughput and resin type. The unique design of the OTX is the result of literally years of development by Moretto in search of reliable, high-level dehumidification of resins with minimum energy usage. Each hopper is encased in Moretto’s exclusive Spyro stainless steel finish, providing optimum insulation and durability. Inside, a unique internal cylinder aligns resin into a uniform mass flow while assuring dehumidified air reaches every pellet. The result is a compact hopper, typically 33% smaller in size than competitive models, and providing a higher level of energy reduction up to 66%. Easy, tool-free access complements the design for cleaning and material changes.

CASE IN POINT: Perfect mass flowing in the drying hopper.
Developed thanks to the mathematical simulations of the supercomputer, Leonardo, our drying hopper creates uniform mass flow from the top to the bottom, so customer material sees the correct time at temperature. Because of this design users will see a 33% reduction on drying time.

X Comb dryers are available in seven models ranging from 5.3 to 52 lbs. per hour of drying capacity and may be enhanced by a series of additional accessories that can create even more drying efficiency.

Blending Solution: Elevating Precision in Microdosing

In micromolding and precision extrusion applications, expensive polymers and additives must be dosed judiciously to avoid waste. Moretto’s recently launched DGM 20 Gravix is the latest addition to its acclaimed DGM multicomponent gravimetric blender series. The DGM 20 Gravix has been specifically designed for the production of small components where high blending accuracy is paramount.

Moretto DGM 20 Gravix blender.

The DGM 20 Gravix embodies Moretto’s commitment to innovation, featuring the exclusive double eyelid shutter valves — a hallmark of precision that sets Moretto apart from competitors. This design ensures the accurate dispensing of resin, regrind, or additives with unparalleled blending accuracy.

Designed to meet the unique demands of low throughput applications with a capacity of up to 44 pounds per hour, the DGM 20 Gravix incorporates Moretto’s proprietary Rotopulse technology that allows control and dose batch up to 0.00017 lb (0.08 grams).

CASE IN POINT: Utilizing the Rotor Pulse Discharge for those critical minor ingredients, you can discharge a couple pellets at a time, which is critical for a precise blends for micromolders.

This innovative solution ensures precise blending, eliminating wasting of expensive additives and mitigating mistakes. The mixing chamber is hemispherical, eliminating dead spots in the mixing chamber so that every pellet is discharged into the machine throat.

Double eyelid shutter valve on Moretto DGM 20 Gravix machines.

Along with its compact footprint, the DGM 20 Gravix is engineered for easy accessibility, easy cleaning, rapid material changes and tool-free maintenance. Its design emphasizes efficiency, from the dust-tight sealed front door to the tool-free removable weigh bin and mixing chamber, ensuring a clean, efficient blending process with no residual cross-contamination.

The stainless-steel supply chambers are equipped with sight glasses and can be easily swapped out for production changes and cleaning. This attention to detail ensures that the DGM 20 Gravix is not only a perfect fit for molding machines or extruders but also meets the stringent precision requirements of high value manufacturing processes.

Heat Transfer Solutions: Optimizing Defined Temperatures and Energy Savings

Precisely controlling mold temperature is crucial to ensure the quality of the final product.

The use of temperature control units (TCU) responds to processors’ needs to bring the fluids of the production lines to very high temperatures in a defined time range. Keeping these temperatures stable for certain periods of time is therefore of key importance and allows optimization of the production cycle and energy consumption.

TE-KO ZERO is a high-performance/ low energy consumption temperature control. It is equipped with a heat exchanger that enables it to work up to 203°F (95°C) and a vibration pump, suitable for working on small molds with narrow passages, guaranteeing constant performance and extreme silence. Made of stainless steel, and suitable for microinjection or extrusion, the TE-KO ZERO is compact and reliable with a heating power of 0.6 kW and offers a simple user interface thanks to the LED control panel.

Moretto TE KO Zero temperature controller.

Connectivity Solution: Tying it All Together

MOWIS is the advanced supervisory control for all Moretto automation that simplifies the management of complex systems and enables connectivity between machines, processes, departments, plants and factories. The platform was entirely developed and designed by Moretto.

Through MOWIS the user controls the status of each piece of equipment and each operation of the system. It manages material usage and production batches, sets and/or modifies process parameters, creates a history, schedules workflow and creates real-time process reports and statistics. MOWIS provides information on the status of machines and identifies their maintenance needs from a predictive perspective and, using historical data, enables forecasting through statistical algorithms and machine learning techniques. Via the OPC UA protocol, Moretto’s MOWIS communicates bidirectionally with MES (Manufacturing Execution System).

The ability to deliver precision equipment that provides real solutions when processing precision, ultra-tight tolerances can be a challenge. But this is where Moretto shines, whether it be auxiliaries for material handling/conveying, drying, blending, temperature control units and more.

Processors producing tiny, high-precision parts need to think holistically when it comes to evaluating and specifying machinery for production. You might be tempted to think the job is done once you’ve selected the properly sized molding press/extruder and tooling packaging. But the role the right auxiliaries play in keeping part quality and consistency in check can’t be overstated.