The core unit is the MFJ-420: 0.8-1.5 t/h from a 7.5-11 kW (15 HP) motor at 2,600 r/min. A Ø424 mm cutter head carries 4 alloy blades (90×60×8 mm) and 12 hammers. Material up to 15 cm in diameter enters a double feed inlet — a wood hopper for logs and boards plus a straw chute for crop stalks — and leaves as uniform 0.2-3 cm chips. Screens from 2 to 20 mm set the fineness (16 mm standard). The machine weighs 150 kg on a 4.5 mm channel-steel frame with a 2.7 mm manganese shell, and every rotor is balanced to within 15 g.
Here is where the MFJ-420 differs from a standard grinder: it is built in four drive versions. The basic motor version is a compact 1,200 × 550 × 750 mm unit for a 380V workshop. The wheeled motor version adds ground wheels for easy one-person movement around a yard. The diesel version is a self-contained trailer, 2,550 × 1,300 × 1,750 mm, running anywhere without mains power — ideal for forestry and roadside work. The PTO version runs from a tractor's PTO shaft. Capacity, voltage, colour and logo are also customized.
Output serves energy and farming alike: 3-8 mm chips for biomass pellets, sawdust for mushroom bags, bedding for livestock sheds, and coarse chips for compost, MDF and paper mills. Zhengzhou Weiwei Machinery has built agricultural machinery since 1980, holds EU CE and ISO9001 certification and runs the WEIWEI / Xingyida brands; units ship in export wooden crates, 48 per 20GP container. Send your material and output — admin@weiweimachinery.com or WhatsApp +8619838691608.
