Descripción
WPEKA Hollow Shaft Double Speed Worm Gear Reducer — Coupling-Free Ultra-High Ratio Drive for Heavy Mixers, Agitators & Slow-Speed Feeders
Large industrial mixing vessels, heavy-duty agitator equipment, and slow-speed bulk material feeders often require both a very high reduction ratio AND coupling-free output shaft connection. A single-stage hollow shaft gearbox (WPKA) can deliver coupling-free mounting but only to 1/60 ratio — far short of the ultra-slow speeds many heavy process applications demand. The WPEKA hollow shaft double speed worm gear reducer bridges this gap by combining the coupling-free convenience of an H7 precision hollow output bore with the extreme ratio capability (1/200–1/900) of the two-stage WPE design.
The WPEKA allows the driven shaft (mixer impeller shaft, feeder screw, agitator paddle shaft) to slide directly into the output bore without any coupling — eliminating the coupling alignment complexity while achieving the ultra-low output speeds required for heavy viscous mixing, crystallisation, and slow-rotation process equipment. Available in 9 size groups (40-70 through 155-250 mm), bore diameters 30–110 mm, ratios 1/200–1/900. About Ever-power | Request a Bore Size Consultation
Technical Specifications
Full dimensional data for all WPEKA sizes. S = hollow bore diameter (H7); W×Y = bore keyway. B = housing width at output bore face. HH = lateral height offset. All dimensions in mm; reference speed 1500 r/min.
| Size | Ratio | A | AA | AB | B | BE | HH | HL | LL | H | M | N | E | F | G | Z | HS | U | T×V | S(bore) | W×Y(keyway) | Wt(kg) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 40-70 | 1/200–1/900 | 286 | 195 | 153 | 130 | 87 | 35 | 215 | 105 | 238 | 150 | 190 | 115 | 150 | 20 | 15 | 25 | 12 | 4×2.5 | 30 | 8×33.3 | 20 |
| 50-80 | 297 | 197 | 144 | 150 | 108 | 35 | 250 | 120 | 273 | 170 | 220 | 135 | 180 | 20 | 15 | 30 | 12 | 4×2.5 | 35 | 10×38.3 | 27 | |
| 60-100 | 363 | 231 | 175 | 160 | 120 | 42 | 310 | 150 | 334 | 190 | 270 | 155 | 220 | 25 | 15 | 40 | 15 | 5×3 | 40 | 12×43.3 | 44 | |
| 70-120 | 408 | 256 | 193 | 175 | 140 | 55 | 370 | 180 | 430 | 230 | 320 | 180 | 260 | 30 | 18 | 40 | 18 | 5×3 | 45 | 14×48.8 | 73 | |
| 80-135 | 471 | 298 | 226 | 210 | 160 | 65 | 430 | 215 | 480 | 250 | 350 | 200 | 290 | 30 | 18 | 50 | 22 | 7×4 | 60 | 18×64.4 | 101 | |
| 100-155 | 555 | 354 | 269 | 256 | 190 | 80 | 490 | 235 | 531 | 275 | 390 | 220 | 320 | 35 | 21 | 50 | 25 | 7×4 | 70 | 20×74.9 | 144 | |
| 120-175 | 598 | 379 | 287 | 282 | 219 | 95 | 555 | 260 | 600 | 310 | 430 | 250 | 350 | 40 | 21 | 65 | 30 | 7×4 | 80 | 22×85.4 | 201 | |
| 135-200 | 662 | 425 | 318 | 320 | 256 | 105 | 625 | 290 | 666 | 360 | 480 | 290 | 390 | 40 | 24 | 75 | 35 | 10×4.5 | 85 | 22×90.4 | 293 | |
| 155-250 | 795 | 510 | 380 | 400 | 295 | 103 | 755 | 350 | 800 | 460 | 560 | 380 | 480 | 45 | 28 | 85 | 40 | 12×5 | 110 | 28×116.4 | 462 |
* S = hollow bore diameter (H7 tolerance). Driven shaft must be ground to h6/js6 for correct fit. W×Y = bore keyway dimensions. B = bore-face housing width. HH = lateral housing height offset. HS/U/T×V = standard solid input shaft dimensions.
Product Structure — Two-Stage Cascade with H7 Hollow Output Bore
The WPEKA replaces the solid output shaft of the WPEA with a precision-bored through-bore in the second-stage worm wheel shaft. The bore is ground to H7 tolerance and fitted with an internal keyway. The driven shaft slides directly into the bore from the housing face — located radially by the bore and rotationally by the keyway — creating a direct, compact, coupling-free connection to the process equipment shaft.
| Drive Stages | Two worm-and-wheel pairs in series; ratio 1/200–1/900 |
| Output Bore | H7 precision hollow bore with keyway; 30 mm (size 40-70) to 110 mm (size 155-250) |
| Bore Tolerance | H7 — mates with shaft ground to h6/js6 for precise radial location |
| Input Shaft | Standard solid shaft with keyway; 5 direction positions (A–E) |
| Housing | FC25 cast iron; same footprint as WPEA with bore-face housing width extension |
| Axial Retention | Set screw standard; shrink disc optional for heavy reversing loads |
✅ Key Features & Benefits
Coupling-Free Output at 1/200–1/900 Ratios
The WPEKA is the only product that simultaneously delivers coupling-free hollow bore output AND two-stage 1/200–1/900 reduction. Where the single-stage WPKA can provide hollow shaft mounting to 1/60 and the solid-shaft WPEA can provide two-stage ratios, the WPEKA delivers both in one unit. Keywords: hollow shaft double speed worm gearbox, two-stage hollow bore worm reducer 1/900.
Direct-to-Shaft Integration for Complex Process Equipment
For large crystallisation vessels, heavy viscous material mixers, and slow-rotation reactor agitators where the impeller shaft is long and the coupling attachment point is difficult to access, the WPEKA’s direct bore-mount eliminates the coupling without requiring accessible shaft end clearance for coupling assembly.
FC25 Cast Iron for Heavy-Duty Service
The two-stage FC25 grey cast iron housing provides the impact resistance and vibration damping needed for heavy mixing and agitation applications where cyclic loads, material consistency changes, and start-stop duty create challenging mechanical environments.
Precision Bore H7 — No Field Reaming
The hollow bore is machined and ground to H7 tolerance in our facility — driven shafts ground to h6/js6 mate directly without field reaming or fitting. This is important for large mixer installations where on-site machining is impractical.
Five Input Shaft Direction Options
Standard positions A through E maintain full installation flexibility for the WPEKA, allowing integration into heavy mixer and agitator drives from any input shaft direction to suit the motor position and machine layout.
Wide Bore Size Range for Heavy Process Shafts
Bore diameters from 30 mm (size 40-70) to 110 mm (size 155-250) cover the full range of impeller shaft, agitator shaft, and screw shaft diameters used in heavy process equipment applications — from small laboratory reactors to large industrial mixing vessels.
Industry Applications
The WPEKA is the solution for heavy process applications requiring both coupling-free shaft mounting and ultra-high reduction ratios:
Large Chemical & Crystallisation VesselsHeavy crystallisation reactor agitators, large industrial mixer vessels, and specialty chemical blending tanks requiring ultra-slow impeller speeds (1/400–1/900 of motor speed) with coupling-free shaft engagement.
Heavy-Duty Agricultural & Feed MixersLarge animal feed mixer drum drives, industrial grain blending vessel drives, and fertiliser mixing plant drives requiring very low-speed high-torque hollow shaft coupling-free direct mounting.
Mining & Mineral ProcessingThickener raking slow drives, heavy flotation cell agitators, and mineral leaching tank mixing drives where the WPEKA mounts directly onto the agitator shaft without coupling hardware.
Industrial Food & BrewingLarge brewing vessel agitator drives, industrial food blending drum drives, and commercial sauce/condiment mixing vessel slow-speed drives requiring coupling-free compact hollow shaft mounting.
Specialty Chemical ProcessesPolymer dissolution vessel drives, textile dye vessel agitators, and industrial adhesive mixing vessel drives requiring very low impeller speed from compact, coupling-free two-stage hollow shaft units.
Waste & Environmental TreatmentIndustrial sludge mixer drives, heavy compost turning drum drives, and organic waste bioreactor agitator drives requiring ultra-slow rotation with direct hollow shaft coupling-free mounting.
Quality Control & Certification
ISO 9001:2015 & CE
Full ISO 9001:2015 QMS. CE Declaration of Conformity per shipment. WPEKA hollow bore verified to H7 tolerance by calibrated plug gauge, and bore-to-second-stage-shaft concentricity checked (≤0.05 mm TIR) on every unit before shipment.
Two-Stage Bore Run Test
Each WPEKA undergoes the standard two-stage run test (noise ≤75 dB(A); oil seal integrity; torque within ±5% of rated) PLUS bore H7 plug gauge measurement and bore concentricity check. Both gear stages and the hollow bore are verified before shipment.
Material Standards
Housing: FC25 cast iron (≥250 MPa). Both worm shafts: 20CrMnTi (≥58 HRC). Wheel rims: ZCuSn10Pb1 tin-bronze. Custom bore diameters for non-standard shaft sizes available with material certification on request.
Why Choose Ever-power for WPEKA Gearboxes
We supply WPEKA hollow shaft two-stage gearboxes to industrial mixer OEMs, heavy agitator equipment manufacturers, and mineral processing equipment builders in Italy, Mexico, Korea, Australia, and over 60 countries. Our in-house internal grinding capability ensures WPEKA hollow bores are machined to H7 tolerance in a single clamped operation — maintaining concentricity with the second-stage worm wheel shaft centreline for correct driven shaft alignment without field adjustment.
- ✅ In-house internal grinding — H7 bore to ≤0.05 mm TIR concentricity
- ✅ Two-stage bore run test — gear set AND bore verified every unit
- ✅ Custom bore diameters for non-standard heavy process shaft sizes
- ✅ Shrink disc option for heavy reversing or high-torque agitator applications
- ✅ 20+ years export record — Italy, Mexico, Korea, Australia and beyond
⭐ Customer Reviews
“We use WPEKA units on our large crystallisation vessel mixer drives. The hollow bore direct-to-shaft mounting eliminated the coupling arrangement that was our most common maintenance call-out on this mixer type. At 1/600 ratio, the impeller turns at exactly the ultra-slow speed our crystal growth process requires. H7 bore dimensions are consistently correct. Excellent product.”
Tony B., Process Engineer
Industrial Mixing Equipment OEM, Victoria, Australia
“We integrate WPEKA gearboxes into our heavy agitator vessel drives. The two-stage hollow shaft solution is unique in the market — nothing else delivers 1/900 ratio WITH coupling-free hollow bore output in a single compact unit. Build quality is excellent and bore dimensions are consistently within H7 tolerance. Highly recommended.”
Marco B., Machine Design Engineer
Chemical Vessel Equipment, Turin, Italy
“We use WPEKA-100/155 on our large industrial animal feed mixer drives. The 1/800 ratio achieves the very slow drum rotation our mixing process requires, and the hollow bore mounts directly onto our drum shaft without any coupling. The two-stage hollow shaft combination is the right specification for heavy feed mixing applications.”
Park S., Senior Engineer
Feed Equipment Manufacturer, Gyeonggi, South Korea
“Good quality WPEKA units for our mining thickener rake drives. The hollow bore at 1/600 ratio handles the ultra-slow rake rotation with direct shaft engagement. H7 bore is correct. One delivery was slightly delayed but Ever-power communicated well and resolved the issue. Would recommend for heavy process mixer applications.”
Jorge H., Technical Manager
Mining Equipment Supplier, Monterrey, Mexico
❓ Frequently Asked Questions
What is the difference between WPEKA and WPKA?
The WPKA (single-stage) achieves ratios 1/5–1/60 with an H7 hollow output bore. The WPEKA (two-stage) achieves 1/200–1/900 — far higher ratios — also with an H7 hollow output bore. Both eliminate the output coupling. The WPEKA is longer and heavier due to the two-stage housing, but delivers the extreme reduction ratios that heavy process applications require beyond the single-stage limit.
How do I specify the correct hollow bore size for my driven shaft?
The bore diameter S must match your driven shaft diameter exactly. The WPEKA bore is H7 tolerance — your shaft should be h6 or js6. If your shaft falls between standard bore sizes, custom bore diameters are available for OEM orders. Contact us with your shaft diameter: we can provide custom bores from our minimum to maximum sizes within each frame group.
What is the maximum hollow bore diameter available for WPEKA?
The largest standard WPEKA bore is 110 mm for size 155-250. For size 135-200, the standard bore is 85 mm. Custom bores up to the maximum for each size group can be specified on request. Contact us with your required bore diameter for availability and pricing.
Can the WPEKA handle reversing rotation and stop-start duty?
Yes — the two-stage worm gear arrangement handles bidirectional rotation, and the hollow bore keyway transmits torque equally in both directions. For heavy reversing duty (e.g. mixer drives with frequent directional reversals), we recommend the optional shrink disc axial retention rather than the standard set screw, to prevent shaft walking under the higher transient axial forces during reversal.
What is the two-stage transmission efficiency of the WPEKA?
The WPEKA transmission efficiency is the product of the two individual stage efficiencies. For a 1/200 ratio combination (e.g. two 1/14 stages), combined efficiency may reach 45–55%. For 1/900 ratio combinations, combined efficiency is typically 30–40%. This lower efficiency compared to single-stage units means the WPEKA generates more heat per unit of output power — for continuous applications at high combined ratios, consider the WPEKS finned variant.
Coupling-Free Ultra-High Ratio Drive — Get WPEKA Quote Today
Whether your heavy mixer needs 1/400 or your reactor agitator requires 1/900, the WPEKA delivers coupling-free hollow shaft mounting at ratios no single-stage product can achieve. Our engineers will confirm bore size and provide a free selection calculation.
