Double Screw Volumetric and Gravimetric Dosers DUALFEEDER
series DFH, DFHW, DFHY
Double screw volumetric dosers series DFH

Double screw gravimetric dosers on single point load cell platform series DFHW

Double screw gravimetric dosers installed hanging on load cells series DFHY

The dosing tool for the DUALFEEDER dosers consists in a couple of twin and co-rotating horizontal screws.
They are machines used to dose good flowing products.
The two DUALFEEDER dosing screws have different dimension and they are not compenetrating and are operated indipendently of each other in order to make them rotate also with different speed.
The DUALFEEDER is a double doser which can cover a wide capacity range because it can make high throughputs using both the dosing screws at the same time but also obtain very low capacities working only with the smaller one.
The geometry of the body of the dosers DFH, DFHW e DFHY it is similar to the twin screw one BH, BHW e BHY. The dosing screws and the agitator available on the entire range DUALFEEDER have the same shape and geometry of the ones used for single screw dosers CH, CHW e CHY. So for the constructive modes and the materials used.
The transmission groups that move the dosing screws and the horizontal agitator are constituted by worm type gearboxes and three-phase electric motors. For the dosing screws, brushless type motors can be used that allow to obtain very slow speed to and consequently very low capacities.
The shaft mechanical seals are made with shielded bearings and dust tight rings available in various materials such as NBR, SILICONE, PTFE and VITON. Air flushed sealing groups are also available for the hardest cases.
Atex certified motors are available eventually equipped with a temperature probe and a anti-condensation heating devices when it is requested.
The dosing screws motor can be controlled by a frequency converter, and can be eventually servoventilated. The brushless type motors are controlled by their specific digital servo-drive . Using these controlling devices it is possible to regulate the rotation speed of the dosing screw in order to obtain the wanted capacity in a predefined minimum and maximum range. The real achievable capacity range depends also on the characteristics of the product to dose. Generally it can be covered a range from 1 to 50 between minimum and maximum.
The transmission groups can be equipped with a device for detecting the direction of rotation of the dosing screws and of the horizontal agitator. The device is made of a inductive sensor and a flap keyed on the slow shaft of the gear motor. Everything is protected by an aluminum restraint box with a transparent polycarbonate sight glass.
The entire range of dosers DFH, DFHW e DFHY is constituted by 12 standard sizes that allow to cover a capacity range from a minimum of 0,1 kg/h to a maximum of 10.000 kg/h.
The most indicated use for DUALFEEDER dosers is the dosing of a big batch accurately and in a short time.
In batch processes the dosing time depends on the total production cycle. Normally high production capacities correspond to short cycle time, it involves the use of dosers dimensioned to make high ranges but at the same time capable to ensure good accuracy.
In this case the doser is necessarily gravimetric equipped with proper weigh controller. With DUALFEEDER dosers it is possible to obtain very high accuracy by operating only the smaller dosing screw in proximity of achieving the pre-set weight (fine dosing). So the DUALFEEDER allows to cover high rates, operating with both the dosing screws, also granting a very high accuracy working only with the smaller one.
In the gravimetric version, the doser can be installed on a proper platform scale (DFHW) or hung to load cells with its hopper (DFHY). The load cells are off-center or flexion type, made in aluminium or in stainless steel with protection grade up to IP67, available also with Atex certification when requested.
Both volumetric DFH and gravimetric DFHW and DFHY dosers can be Atex 21/22 and Atex 21/21 certified, if required.
The hoppers available for this type of machine are the same, relatively to the shape and accessories supplied, as the ones of the dosers CH and BH. Also the vertical spouts are the same with or without automatic closing devices.
Electrical control panels can also be supplied including software specifically designed accordingly to the requested functionality.
The geometry of the body of the dosers DFH, DFHW e DFHY it is similar to the twin screw one BH, BHW e BHY. The dosing screws and the agitator available on the entire range DUALFEEDER have the same shape and geometry of the ones used for single screw dosers CH, CHW e CHY. So for the constructive modes and the materials used.
The transmission groups that move the dosing screws and the horizontal agitator are constituted by worm type gearboxes and three-phase electric motors. For the dosing screws, brushless type motors can be used that allow to obtain very slow speed to and consequently very low capacities.
The shaft mechanical seals are made with shielded bearings and dust tight rings available in various materials such as NBR, SILICONE, PTFE and VITON. Air flushed sealing groups are also available for the hardest cases.
Atex certified motors are available eventually equipped with a temperature probe and a anti-condensation heating devices when it is requested.
The dosing screws motor can be controlled by a frequency converter, and can be eventually servoventilated. The brushless type motors are controlled by their specific digital servo-drive . Using these controlling devices it is possible to regulate the rotation speed of the dosing screw in order to obtain the wanted capacity in a predefined minimum and maximum range. The real achievable capacity range depends also on the characteristics of the product to dose. Generally it can be covered a range from 1 to 50 between minimum and maximum.
The transmission groups can be equipped with a device for detecting the direction of rotation of the dosing screws and of the horizontal agitator. The device is made of a inductive sensor and a flap keyed on the slow shaft of the gear motor. Everything is protected by an aluminum restraint box with a transparent polycarbonate sight glass.
The entire range of dosers DFH, DFHW e DFHY is constituted by 12 standard sizes that allow to cover a capacity range from a minimum of 0,1 kg/h to a maximum of 10.000 kg/h.
The most indicated use for DUALFEEDER dosers is the dosing of a big batch accurately and in a short time.
In batch processes the dosing time depends on the total production cycle. Normally high production capacities correspond to short cycle time, it involves the use of dosers dimensioned to make high ranges but at the same time capable to ensure good accuracy.
In this case the doser is necessarily gravimetric equipped with proper weigh controller. With DUALFEEDER dosers it is possible to obtain very high accuracy by operating only the smaller dosing screw in proximity of achieving the pre-set weight (fine dosing). So the DUALFEEDER allows to cover high rates, operating with both the dosing screws, also granting a very high accuracy working only with the smaller one.
In the gravimetric version, the doser can be installed on a proper platform scale (DFHW) or hung to load cells with its hopper (DFHY). The load cells are off-center or flexion type, made in aluminium or in stainless steel with protection grade up to IP67, available also with Atex certification when requested.
Both volumetric DFH and gravimetric DFHW and DFHY dosers can be Atex 21/22 and Atex 21/21 certified, if required.
The hoppers available for this type of machine are the same, relatively to the shape and accessories supplied, as the ones of the dosers CH and BH. Also the vertical spouts are the same with or without automatic closing devices.
Electrical control panels can also be supplied including software specifically designed accordingly to the requested functionality.