Magnabloc – a new series of vacuum extruders
The Monobloc line developed in 1967 combined significant improvements with regard to accessibility and ease of maintenance. Key features were low running costs and reduced energy consumption. The line of extruders has been progressively developed over the years, but has remained faithful to its core operating principle; a compact and efficient design featuring a single reducer for the mixing and extrusion process.
The new range of Magnabloc extruders concentrates Verdés’ extensive experience in extrusion, while at the same time retaining the hallmark original design:
three main shafts driven by a single reducer
feeding paddles synchronized with main auger
self-supporting structure for quick and easy set-up
By maintaining its mixing and extrusion efficiency and few mechanical parts, the Magnabloc series achieves maximum performance at reduced power consumption and minimum operating costs, thus providing a fast return on investment.
The most important improvements this line of products brings include the following:
Mixing zone
One of the highlights of this extruder is the system of individually adjustable mixing knives that ensures perfect adaptability to the different mixtures and wetting needs, as well as the “knife-on-knife” effect, unique to Verdés mixers, which enhances homogenization and blending in of additives. The new shape of mixing knives favours a deeper penetration into the clay, reducing wear and energy consumption. Moreover, the shaft and trough protectors are easily replaceable and deliver great functionality and a longer service life.
Vacuum chamber
The large-volume vacuum chamber ensures perfect de-airing of the clay and excellent filling of the rear extrusion auger. The internal walls are lined with replaceable liners to form a highly tapered profile preventing formation of layers of dry material. These liners can be supplied in wear-resistant or non-stick plates. This area is where the feeding knives are housed, which are synchronously driven to the main shaft and physically penetrate into the perimeter of the extrusion auger to improve filling and efficiency.
Reducer
Designed according to proprietary Verdés brand concepts, it aims at achieving maximum load availability and efficiency for a wide range of production applications and operational pressures. As a parallel shaft reducer with case-hardened and ground helicoidal gears, it ensures a progressive load transmission and quiet operation. This system is more compact in the new range and has been redesigned to allow for traditional belt drive, with or without clutch.
Control and safety
The extruder offers several options for axial pressure control which constantly measure shaft load, protecting the machine when the pressure reaches a predetermined limit. These control systems make it possible to detect pressure increase prior to an accurate reading of the plastometer.
Basic: Safety system based on the monitoring and control of power consumption and extrusion hardness
Hydraulic: A pressure reading is obtained from a hydraulic chamber, on which the thrust bearing is supported
Load Cells: The reading comes from three load cells, arranged at 120° to each other
Augers
Available configurations include cylindrical, conical and extra-conical augers, to offer suitable solutions for any product – hollow, solid or large-format – for specific working conditions. The Verdés range includes highly wear-resistant chromium alloy augers and various solutions coated with chromium and tungsten carbides.
All parts in contact with the mixture are protected with replaceable anti-wear elements. The auger’s body has also been upgraded with a screw-free protector-fastening system that ensures sealing.
Summary
The Magnabloc series features many innovations, but it goes one step further as a compact and efficient extrusion concept that makes it simple and quick to perform maintenance tasks and – most importantly – guarantees top performance under any conditions.
Talleres Felipe Verdés, S.A.
www.verdes.com