Since Reifenhäuser launched its first commercial gearless extruder at NPE 2003, about 200 extruders with gearless motors have been on the market over the past year or so. Although the main manufacturers and users are located in the European market, the United States has only a few production and use, but the continuous expansion of the application field is showing a spurt.
Extruder manufacturers enthusiastically develop
Gearless extruders have the advantages of low vibration, low noise, maintenance-free, water-cooled, dust-proof, almost no need of lubricating oil, convenient screw disassembly and overhaul, stable torque over the entire speed range, and the compact structure of the motor. Particularly suitable for co-extrusion processing. In order to seize market opportunities, various extruder manufacturers have gradually invested in development. This not only rapidly expands the market, but also expands the application area.
On the K2001, Reifenh?user introduced the prototype of a gearless extruder based on Reitorque technology for the first time, causing a huge stir. The machine uses a gearless motor from Swiss Etel Motion Technologies. Since then, on the NPE 2003, Reifenh?user introduced the first gearless extruder for pipe processing and for the first time commercialized it. This equipment uses permanent magnet synchronous motors from Siemens, Germany.
In K2004, a number of extruder manufacturers launched a newly developed gearless extruder. Reifenhäuser launched a three-component film-free co-extrusion line. Two of the three extruders use 60 screws and the other uses 80 screws to produce a 1.7-m wide composite film. The German company esde has developed a two-layer cast film production line using Oswald's 500Nm MF motor with a screw diameter of 50mm. Cincinnati Extrusion also purchased a TF motor for its new Proton extruder but equipped with a pair of reduction gears. Battenfeld has sold more than 20 gearless BEX extruders to the market within eight months of the launch of the first machine. Davis Standard was the first American company to use a synchronous torque motor. The company's first gearless extruder used a 1FW2 synchronous torque motor from Siemens.
After more than a year of market development, the gearless extruder has been extruded from the first small-size pipe, and has gradually developed into processing fields such as sheet, film, casting, and co-extrusion. From the point of view of the type of equipment, more and more applications have been obtained in injection machines and various auxiliary equipment.
Motor suppliers are optimistic about market potential
Three motor manufacturers, Siemens, Baumuller, and ABB, who are optimistic about the broad prospects of gearless motors in the field of plastics processing, participated in the professional exhibition NPE2003 for the plastic industry for the first time last year. The gearless motors currently used for extrusion processing in the market are mainly permanent-magnet synchronous motors. Because they have the characteristics of constant torque at low speeds, they are particularly suitable for extruders.
Permanent magnet synchronous motors have been on the market for nearly 20 years, but due to their large size and high value, they were initially used mainly in military fields such as radar telescopes and cruise missiles. They were gradually expanded to elevators, machine tools, Printing and other fields. The progress in the application of extrusion processing has benefited from Siemens' development of a small, gearless, high-torque, low-inertia hollow shaft motor that is different from the past. The product introduced by Siemens was originally used in the injection machine of Krauss-Maffei. After continuous development and improvement, the torque of the motor has been increased to 11,000 Nm at a speed of 20 to 500 rpm. At present, 11,000 Nm permanent magnet synchronous motors are being tested by the Reifenhäuser R&D department.
Motor manufacturers are not satisfied with this and are actively developing permanent magnet synchronous motors with higher torque. The 11,000 Nm torque is only suitable for the 100 mm model for the extruder, and the 120 mm to 150 mm models commonly used in the field of blown film and cast film do not provide sufficient power. Oswald Motor Company stated: "In 1 to 2 years, we will introduce permanent magnet synchronous motors of 20,000Nm~30,000Nm." Siemens is also working on a similar project with a target of 32,000Nm of torque and 1000 rpm. Meet the power requirements of 120mm blown film units or 150mm cast film units.
New technology gains market recognition
The acceptance of gearless extruders by processors is undoubtedly the biggest development driver for extruder manufacturers and motor suppliers.
The Empur company in Buchholz-Mendt, Germany, was the first tube mill to use a gearless extruder. In May 2003, Reifenhäuser's Reitorque extruder was used to produce small geothermal PE hot water pipes. Empur thinks that the energy-saving effect is very significant, enough to buy five more devices of the same type. The extruder is equipped with a very small motor with a torque of only 750 Nm. Its competitor, Aquatherm in Attendorn, Germany, also installed a 50mm Reitorque extruder last month with a torque of 7000Nm.
Nordfolien of Steinfeld, Germany, started using Reifenhäuser's Reitorque extruder in July. The company believes that the new extruder has no problems in its use, but the time is too short to evaluate the energy-saving effect. The Oldroyd AS company in Sannidal, Norway, started using the Reitorque extruder in June with a torque of 7000 Nm for the production of vacuum thermoformed sheets. In addition, according to information, there are currently more than 50 film factories in the world using extrusion equipment equipped with gearless motors, including three US factories.
The recognition of the market has also greatly stimulated the confidence of equipment and motor developers. Reifenhäuser plans to use its gearless extruder below 100mm as a standard configuration, and the next step is to target models below 150mm. Siemens also believes that in the coming year, gearless extruders will expand from 5 to 6 new applications.
Gearless extruders not only have new technology advantages, but also have cost advantages. Although the gearless motor is more expensive than the ordinary motor, the overall cost is equivalent to the usual configuration due to the simplified structure of the entire machine. In addition, the gearless extruder also has the advantages of energy saving, space saving, maintenance-free, and easy disassembly and assembly. The market application in the past year has shown great potential.