SEW-EURODRIVE K87AD3ZR Gear Reducer 7.21 To 1 Ratio

SEW‑EURODRIVE K87AD3ZR is a three‑stage explosion‑proof (ATEX II2GD) helical‑bevel gear reducer from the K series, offering a 7.21:1 reduction in a compact footprint for hazardous‑environment applications. This size 87 unit is part of SEW‑EURODRIVE’s K series, which covers sizes from 37 to 187 and provides gear ratios from 3.98 to 197.37; the 7.21:1 configuration aligns with the model code. The modular family supports foot‑ or flange‑mounted configurations (B5 or B14 flanges) and both solid and hollow shaft options; hollow shafts can be configured with keyed connections, shrink disks, splined shafts, or TorqLOC for secure coupling. Typical uses include pallet conveyors, belt conveyors, chain conveyors, hoists and lifting stations, freight elevators, and travel and lifting drives in stacker cranes. The gear unit emphasizes high efficiency gearing, robust seals, and high fatigue‑strength gearing for long service life in demanding environments, with variant options including reduced‑backlash versions to improve precision in positioning tasks.