The hoppers series MXV are slow vertical mixers generally aimed to homogenize various kinds of powder products, even if they are poorly flowing and with an aggregation tendency. They can be used also for granular or flakes products.

The hoppers MXV are mostly installed on the compound extrusion lines in the plastic industry. They are the receiving point of the raw materials that are dosed upstream and then transferred on the line with proper conveying systems. The function of the hoppers MXV is to mix and reaggregate various products that segregated during the transport so the feeding line is made with a homogeneous blend.

The transport systems can be mechanic, for example with screw conveyor, or pneumatic type with vacuum loaders series ATS, AJS, ATSY and AJSY with relative vacuum units series UATC, UATV and UAVL.

There is also a gravimetric version ( MXVY ) where the mixing hopper is equipped with outer supporting brackets that allow the installation on load cells. This setup is adopted when the dosage upstream is in batch mode. With the hopper MXVY it is possible to manage the transport system in order that the batch is completely transferred; otherwise there is the risk to feed the extruder with a partial composition and allegedly wrong of the recipe. The load cells used are off-center, flexion or shear beam type, aluminum or stainless steel, available also in the Atex version when it is requested.

More in general the vertical mixers MXV and MXVY can be used to homogenize the dosed products with Multiple Dosing Stations series MDA, MDAL, WB, VDOS and WDOS because of the risk of separation of the products in consequence of their eventual transport, or simply when they descend by gravity from a storage hopper.

The mixing hoppers MXV and MXVY have a cilindrical shape with a conical bottom equipped with a discharging valve. The conicity can vary according to the angle of descent of the products and consequently according to the permanence time in the hopper needed. A correct mixing time, together with the rotation speed of the mixing device is fundamental to obtain a good homogenisation.

The unloading valve can be manual or automatic electro-pneumatically controlled.

For the granular products it is used a particular double blade gate valve with dovetail profile to prevent the gripping.

The mixing device is constituted by a vertical agitator. Are available different types of agitators to use according to the products characteristics to mix, and also their relative percentages, in order to obtain the best result. Specifically the vertical agitators are constituted by a main shaft to whom different shaped carpentry arms are welded. The most used shapes are blades, ploughshare, spiral, helical sections or also a combination of them.

The mixing device is installed on the hopper lid. The lid is bolted to the hopper body in order to extract totally the mixing device to accomplish the ordinary cleaning and maintenance operations. On the lid there are also a loading inlet with a vent socket in case of automatic filling, or an openable drop-down door, with protection grid underneath, and eventual safety microswitch in case of manual filling.

The transmission group that drives the mixing device is constituted by worm type gearboxes and three-phase electric motors dimensioned to be controlled by a frequency converter and equipped with servo-ventilation when needed. In this way it is possible to adjust the rotation speed of the mixing device in order to obtain a better result.

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 an anti-condensation heating device when it is requested.

The transmission groups can be equipped with a device for detecting the direction of rotation of the mixing device. The device is made of an 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.

Eventual minimum and maximum level sensors complete the setup of the mixing hoppers MXV to manage the automatic load and unload phase.The most used sensors are capacitive types, rotary level sensors, vibrating level switches to choose according to the product characteristics.

The most used construction materials are stainless steel Aisi 304 and 316L, but it is also possible to provide carbon steel on request.

The surfaces in contact with the product can be easily pickled or mirror polished to ease the cleaning. It is possible to have certifications of the contact materials on request.

The external surfaces are satin finished 180 mesh. It is possible to have them glass bead blasted or electro-polished on request.

The gaskets are made in dust-tight rubber , such as SBR or NBR. They are available also with FDA certification on request.

The mixing hoppers MXV and MXVY can be Atex 21/22 and Atex 21/21 certified 

Electrical control panels can also be supplied including software specifically designed accordingly to the requested functionality.