GRANULATORS | TECHNOLOGY
is collected at the moulding machine and brought in for grinding. Each conveyor belt is colour-coded with the various scrap colours – black plus four other colours. Scrap is vacuum conveyed out of the granulator catch bins and then ‘air washed’ to remove the dust and fines. The regrind discharges from the fines separation system, through a metal separator that removes any tramp metal particu- lates, and into a surge bin before it is reintroduced into the process. The granulators are also equipped with optional side chutes for feeding long, thin parts that cannot be fed into the front of the unit. Other custom configurations frequently request- ed by customers include units with low-profile hoppers for easy integration with a moulder’s runner separation system. In fact, almost any hopper configuration imaginable can be delivered. For handling heavy, thick-walled scrap, or espe- cially high volumes, granulators can be paired with shredders, with automatic custom conveyors and evacuation systems that are fully integrated both mechanically and electrically for a seamless operation.
On the controls side, PLC controls allow users to
remotely monitor the function of the granulator or size-reduction system and/or tie individual granula- tors to a central control system for plant-wide moni- toring and automatic start/stop. Wittmann has developed the S-Max 3 screen-
less granulator with an optionally available built-in feeding shaft that can help avoid bridging, espe- cially in case of grinding long runners and flat
www.plasticsrecyclingworld.com
parts. The company adds that compared to conventional blade granulators, screenless granu- lators provide a number of benefits such as energy efficiency, less noise, clean and uniform regrind from hard, brittle plastics such as ABS, PC, ABS+PC, PA and reinforced plastics. The granulator motors have high torque, the units run smoothly at a low speed (27 upm at 50 Hz) without stalling, and they are suited for cutting thicker sprues and/or parts to a pellet size from 4-10 mm. An additional feeding shaft – offered as an option for the Wittmann S-Max 3 granulator – keeps large parts in motion, and pre-breaks them, helping to avoid bridging or nesting of parts. The shaft also helps to avoid downtime eventually caused by material backing-up or material overflow, and keeps the production process running smoothly. The optional Wittmann feeding shaft is indepen- dently driven and has elongated hooks to pre-cut the parts and push them into the cutting chamber for regular grinding, after the shaft has reduced the dimensions of the parts – and this may allow the use of an altogether smaller type of granulator, possibly saving capital expenditure.
CLICK ON THE LINKS FOR MORE INFORMATION: �
www.cmg.it �
www.hellweg-granulators.com �
www.rapidgranulator.com �
www.weima.com �
www.neue-herbold.com �
www.conairgroup.com �
www.wittmann-group.com
Left: The opened material hopper of Wittmann’s S-Max 3
Above: In this custom granulator installation by Conair, the conveyor belts feeding the grinders are colour coded to match the colour of the scrap. Regrind is automatically ‘air-washed’ to remove dust and fines and conveyed to surge bins
September 2021 | PLASTICS RECYCLING WORLD 65
IMAGE: WITTMANN IMAGE: CONAIR
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72
