‘New generation’ extrusion equipment unveiled
A new generation of extrusion equipment for the snacks industry was showcased by Baker Perkins at the recent Snackex trade show in Austria.
The SBX Master twin-screw extruder range for snacks has been redesigned and a new preconditioner added to the range to increase flexibility.
The company also highlighted its MPF24 small batch extruder for development work and low production runs; the new sheet and cut process for extruding baked snacks; and its co-extrusion capability.
The flexibility of the modular SBX Master extruder has been improved by increasing power, torque and speed. This, along with a range of barrel lengths, increases the variety of end products that can be made while barrel diameters between 50mm and 125mm give an output range from 500 to 2,300kg per hour.
Improved barrel cooling also contributes to expanding the range of products that can be made and also helps to improve quality and consistency. The new design features water distribution channels located closer to the internal surface of the barrel to improve responsiveness and the rate of heat transfer. Flow rate is increased and cooling can be controlled and adjusted to individual product profiles.
The arrangements for mounting the die and cutter have been simplified to make changeover, cleaning and maintenance faster and safer. The die is supported on a hinged arm that enables it to be moved quickly and safely, especially when hot, while the cutter slides in and out of position on rails. This is a pneumatically-operated, pushbutton-operated system that automatically puts the cutter directly in front of the die as soon as the extruder is ready, leaving only fine adjustment to the operator. This, the company says, minimises time and waste generated during set-up, changeover or if a blade change is required during a run.
A gearbox condition monitoring system that reduces unexpected downtime is available on all new SBX extruders and can also be fitted to existing machines.
The preconditioner, meanwhile, adds flexibility to snack production when applied to denser and/or shear sensitive materials, according to Baker Perkins. It is suitable when processing pellets for half products formed in the extruder and expanded elsewhere such as multigrain chips. It is also ideal for protein products, where energy input in the preconditioner replaces mechanical shear energy in the extruder in order to avoid protein damage.
It comprises two processing chambers, each fitted with a mixing shaft, which provide a first-in, first-out process flow. In the first chamber, high intensity mixing of the dry and liquid ingredients takes place while steam is injected to heat and hydrate the ingredients. The second chamber allows the energy and moisture to equilibrate throughout the preconditioned mass, minimising clump formation and achieving an optimised mix profile for subsequent processing by the extruder.