Special Report: Companies push array of hot-runner technologies
At the K show, companies introduced hot-runner components that have been configured to increase the efficiency of high-speed, multicavity molding for packaging, medical, automotive and consumer product applications.
SLIM NOZZLES FOR TIGHT SPACES
Incoe International Europe, Rödermark, Germany, extended its DF line of nozzles with several new slim models for use in tight spaces that have gates placed deep in the mold. DF nozzles are used with Incoe's Direct-Flo hot-runner system. The nozzles are geometrically balanced, and are screwed directly into the manifold to create a compact module with minimal distances between cavities. The DF series is suited for use with multicavity molds or for difficult-to-reach gating points, marketing manager Reinhard Kabus said.
A new, slimmer DF 12 nozzle, launched at the K show, is long, yet maintains uniform temperatures. It can be combined with Incoe's MultiPower heater to provide thermal control over the entire length of the nozzle. Just two heating zones are required to handle a DF nozzle almost 2 feet long. Minimizing the number of heating zones cuts costs, yet optimizes process conditions, Kabus said. The MultiPower heater features fully integrated heating wires, easily interchangeable thermocouples and a central cable outlet at the nozzle head for ease of use and maintenance.
In addition, the DF 12 nozzle, together with the MultiPower heater, can also be combined with its compact HEM hydraulic valve-gate cylinder. Such an arrangement protects against heat loss between the cylinder and the manifold, and offers easier access for maintenance. In this arrangement, the nozzle can work as the adjustable shut-off valve pin. The combination delivers pinpoint injection in a tight space, the company said.
Incoe said other developments include the combination of its slim DF 5 nozzle with its Slim Body Heater for tighter cavity spacing within multicavity tools. With the new heater, the outer diameter of the nozzle was reduced by nearly 25 percent and the minimum distance between two nozzles dropped from 22mm spacing to 18mm. The spacing was further reduced, to 16mm, by adapting a nozzle shank to the equipment.
According to Incoe, users can take advantage of the screwed-in nozzle design — which creates a pre-assembled, all-in-one system — while also setting minimal cavity distances to promote more efficient molding with multicavity tools, Kabus said.
ARRAY OF NOZZLES FROM THERMOPLAY
Thermoplay SpA, Pont St. Martin, Italy, a division of Barnes Group Inc., Bristol, Conn., introduced special nozzle designs for packaging, medical products and small parts.
Thermoplay launched a new shut-off nozzle for thin-wall packaging applications that require fast molding speeds, high pressures and rapid cooling cycles. A larger internal bore accommodates faster melt injection rates.
The thermal exchange between the pin and cavity plate has been improved, so it can more rapidly cool the gate area.
The new shut-off nozzle features an improved seal between the nozzle head and the manifold, which has been optimized to compensate for the greater injection pressure generated during fast molding cycles. The improved seal and nozzle prevent leaks even when the system is not fully thermally expanded, such as during cold startup, marketing manager Maria Teresa Pomesano said.
Thermoplay also has developed special nozzles for edge gating. The DL-8B nozzle is suited for parts where the area where the resin is injected is a critical point on the part, or when the shape of the part requires the use of a small tip. The design of the DL-8B keeps the heated part of the nozzle away from the surface of the molded part to avoid spots and part defects.
The DL-8B nozzle can be used for edge-gate or internal molding of parts like caps and small parts. Thermoplay said it is possible to customize the distance from the injection point to the nozzle axis with the new nozzle.
Thermoplay also unveiled the DL-1B nozzle with an extended tip, also for use when the injection point is in a critical position on the part or when the application requires the use of a very small tip.
The DL-1B comes in diameters of 18mm, 22mm, 30mm and 44mm. The tip can be tilted as much as 55 degrees. This allows the nozzle to be used for gating to the interior or exterior of a small part. The nozzle is suited for use with polyolefins and styrenes, such as PP, PE, thermoplastic elastomers, PS and ABS.
Thermoplay also developed a nozzle for medical parts that are traditionally molded with a tunnel sprue. The new nozzle eliminates tunnel sprues, used to make parts, such as syringes, that have long lengths in proportion to their diameters.
The injection points are near the open end of the tube at a sidewall. This minimizes mold core movement and surface imperfections at the injection point, improving part quality. It also enhances part-extraction operations, Thermoplay said.
Thermoplay expanded its line of mini gate nozzles for small parts with the launch of the F011 valve-gate nozzle. The F011 is designed for special applications in packaging, medical cosmetics and electronics. It has a compact profile and is ideal for tight spaces, allowing for injection on an inside surface of a part. The nozzle features a minimum pitch distance of 1mm.
The nozzle and tip arrangement of the F011 generates low thermal dispersion, which in turn allows flexibility in the design of the cooling system. Thermoplay heaters uniformly distribute heat along the length of the nozzle and keep energy consumption low, at a maximum of 100 watts per nozzle.
The F011 can be actuated pneumatically or hydraulically, individually or through plate actuation, and can be adjusted in increments of 0.05mm. The valve-gate nozzles are offered in standard lengths from 56mm to 106mm. Conical or cylindrical pin designs are available and are designed to minimize witness marks and gate vestige, providing a high-quality finish.
In the U.S., Synventive Molding Solutions, Peabody, Mass., also a business of the Barnes Group, represents Thermoplay.
NOZZLE FOR PET PREFORMS
MHT Mold & Hotrunner Technology AG, Hochheim, Germany, introduced a new generation of its Vulcan nozzle line for PET preforms.
The new Vulcan II nozzle has an improved valve bushing and new piston for optimized part production, reduced energy consumption and
maintenance, and extended life.
A new design, including a one-piece cylinder, two-piece piston, new actuator and pneumatic cylinder, makes it easier for operators to access and assemble. The nozzle tip features a new inlay that provides direct heat transfer to the nozzle tip, while a new insulation ring reduces heat losses. The design prevents overstretching of the sealing ring.
The upgraded Vulcan II prevents leakage and keeps dust from collecting inside the piston. Pump performance is better, while air consumption is reduced, sales manager Michael Werner said.
The nozzle tip is accessed by removing the cavity plate in the machine. Disassembly of the thermocouple and heater is simple. Also, service frequency is reduced due to the updated design and ease of access for maintenance.
MULTITIP NOZZLES A FOCUS AT GÜNTHER
Günther Heisskanaltechnik GmbH, Frankenberg, Germany, highlighted the development of its OktaFlow line of multitip hot-runner nozzles, for direct side gating of small parts.
The OktaFlow Type OMT multitip nozzle can have as many as eight tips per nozzle, and can be used in conjunction with a heated adapter or with a manifold for multicavity injection molding. OktaFlow can be used as a single nozzle if it incorporates a heated adapter, said Horst-Werner Bremmer, head of sales and technical consulting.
The pins can be arranged radially, with a center-to-center distance of 45mm or 65mm. They also can be arranged linearly, installed in a mini manifold supported by floating bearings. Both designs optimize the temperature profile for uniform heating. The nozzle design minimizes the effect of thermal expansion.
VALVE-GATE NOZZLE HAS NEW PISTON TECHNOLOGY
Witosa GmbH Heisskanalsysteme, Frankenberg, which makes hot-runner systems, nozzles, valve-gate systems, hot halves and temperature controllers, introduced its NI valve-gate nozzle at the K show.
The nozzle's new piston technology offers a number of benefits. For example, the needle drive can operate without cooling or lubrication, and the needle position can be adjusted directly from the parting plane without dismantling the hot runner. Also, a piston drive in the axis direction of the needle achieves optimal force transmission, sales manager Ravan Graubner said.
The valve-gate nozzle screws into the manifold for complete protection against leaks. The design eliminates dead spots that can hinder melt flow, and the nozzle is compact, so that it takes up less space.
The NI line comes in diameters of 14mm, 16mm or 20mm, which accommodate nozzle lengths from 71.5mm to 171.5mm.
The NI can be used as a single or system nozzle, and works in either a horizontal or vertical injection molding application. The valve is actuated pneumatically and does not require standard polytetrafluoroethylene (PTFE) seals. Made for easy maintenance, it can be used in a range of applications without regard to temperature.
MULTICAVITY MICRO-MANIFOLD FROM EWIKON TARGETS SMALL PARTS
Ewikon Heisskanalsysteme GmbH, Frankenberg, introduced a micro-manifold for making small parts in high-cavitation molds, such as medical devices and closures. Molds with the manifold are more compact than conventional multicavity molds.
The micro manifold is composed of 16-drop clusters. The line includes four styles of micro-manifolds, available in three versions each with different lengths of the rigid part of the electrical connection. Ewikon offers the micro-manifold in configurations with 16, 32, 64, 96, 128 and 192 drops. Complete hot halves with micro-manifolds for 16 to 192 drops are available.
Each drop in the main level of the manifold feeds a balanced micro-manifold on a second level. Micro-manifolds have four screwed-in, heat-conductive tip inserts with flow channel diameters of 3mm and a melt seal at the gate. The screw-in tip inserts can be changed without dismantling the manifold.
Ewikon achieves a fully balanced flow channel layout by placing a main manifold on a second level. Four gates in the micro-manifold system are served by one heating circuit. This approach simplifies wiring and the complexity of the control technology, and minimizes space requirements in the manifold for cabling.
The overall compact design reduces total flow length, pressure drop and residence time. The micro-manifold can be designed with a distance of 30mm between each cavity.
NOZZLE WEAR RESISTANCE IMPROVED WITH UPGRADED COMPONENTS
Mastip Technology Ltd., Auckland, New Zealand, developed new grades of its G5 tips and H5 nuts, which add wear resistance to its MX, BX and SX lines of hot-runner nozzles, marketing manager Cath Sinclair said.
G5 tips are constructed from a highly conductive hard metal, while the H5 nuts are machined from a hard, wear-resistant powdered steel. Designed for use with its X ranges of nozzles, the combination of the tips and nuts offers high performance and reliability under demanding conditions, such as the processing of glass-, mineral- or talc-filled polymers. The combination also improves the corrosion resistance of the nozzle. The G5 tips are available in both torpedo and open-flow versions, with thermal and valve-gate configurations. The H5 nuts are available in bush and sprue versions, and in thermal and valve-gate designs.
EDGE GATE NOZZLE HANDLES WIDER RESIN RANGE
Otto Männer GmbH, Bahlingen, Germany, extended the capabilities of its Edgeline valve-gate nozzles to handle hard-to-process resins. The company optimized the temperature profile of the nozzle to allow the nozzle to be used with temperature- and shear-sensitive materials, said Uwe Reinwand, area sales manager for hot-runner systems. Männer said the newest iteration of Edgeline incorporates a patent-pending temperature-control element.
The first generation of Edgeline was suited to processing only PP, Reinwand said. The second generation of the nozzle was updated to handle demanding materials like cyclic olefin copolymer (COC) and cyclic olefin polymer (COP). The latest generation processes a greater range of sensitive resins, including COC/COP, polymethyl metha-crylate (PMMA), polyamide, PC and thermoplastic elastomers, as well as commodity resin grades, without imparting stress to the resins.
Edgeline nozzles feature pins that move at a right angle to the opening and closing of the mold. With the valve gate, the user can enjoy the benefits of a cylindrical valve-gate hot-runner system while performing applications that require side injection. Features include patent-pending heater elements for the nozzle body, tip and base, and heat-conducting materials that optimize the temperature profile along the entire flow path.
Männer offers Edgeline in two- and four-drop configurations. The two-drop arrangement has axis spacing of 60mm, while the four-point style has axis spacing of 30mm by 60mm.
HUSKY EXPANDS NOZZLE LINE WITH NEW SIZE
Husky Injection Molding Systems Ltd., Bolton, Ontario, highlighted its Ultra Helix 350 from its Ultra Helix line, which is used for direct gating while coming as close as possible to having zero gate vestige.
The Ultra Helix 350 valve gate is designed to resist mechanical wear at the gate. It uses an integrated heater that can be replaced as easily as a removable unit.
The valve gate and heater provide a consistent thermal profile and outstanding cavity balance, allowing a wide processing window. In addition, because of the design of the Ultra Helix 350, heater replacement is easy and requires little calibration.
Mikell Knights, senior staff reporter
Contact:
Ewikon Molding Technologies Inc., 815-874-7270, www.ewikon.com/en
Gunther Hot Runner Systems Inc., 630-293-4650, www.guenther-hotrunner.com
Husky Injection Molding Systems Ltd., 905-951-5000, www.husky.ca
Incoe Corp., 248-616-0220, www.incoe.com
Manner USA Inc., 770-449-1820, www.maenner-group.com
Mastip Inc., 262-644-9400, www.mastip.com
MHT USA LLC., 404-835-1140, www.mht-ag.com
Synventive Molding Solutions, 978-750-8065, www.synventive.com
Witosa GmbH Heisskanalsysteme, 49 6451 230 987-0, www.witosa.de
