{"id":937,"date":"2026-06-18T05:42:57","date_gmt":"2026-06-18T05:42:57","guid":{"rendered":"https:\/\/planetary-gearboxes.com\/?post_type=product&p=937"},"modified":"2026-06-18T05:42:57","modified_gmt":"2026-06-18T05:42:57","slug":"406bw3-winch-drive-planetary-gearbox","status":"publish","type":"product","link":"https:\/\/planetary-gearboxes.com\/hi\/product\/406bw3-winch-drive-planetary-gearbox\/","title":{"rendered":"406BW3 Winch Drive Planetary Gearbox Reducer"},"content":{"rendered":"
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<\/p>\n

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406BW3 \u2014 The 406 Family Heavy-Duty Specialist<\/h2>\n
\n
\n

The 406AW covers every speed. The 406W serves production volume. The EP-406BW3 handles the loads that break the other two. At 17,500 Nm \u2014 40% more torque than the 406W and 4,500 Nm beyond what the 406AW can deliver \u2014 the 406BW3 is the winch drive planetary gearbox<\/a> for machines where the hoist duty is violent: grab cranes slamming clamshells into bulk piles, scrap magnets jerking ferrous debris off stockpiles, dredger buckets tearing through river sediment.<\/p>\n

The three-stage architecture provides the torque headroom that two stages geometrically cannot achieve within the 406 housing diameter. The price is weight (270 kg versus 240 for the 406W) and a narrower ratio window (63-136 versus 28-140). But for grab crane applications, the narrow ratio range is irrelevant \u2014 the grab cycle operates within a fixed speed envelope that 63-136 covers entirely, and the additional 4,500 Nm of torque is the difference between a gearbox that survives the shock loads and one that doesn’t.<\/p>\n<\/div>\n

\n

\"406BW3<\/p>\n

\n
\n
17,500<\/div>\n
Nm Torque<\/div>\n<\/div>\n
\n
430<\/div>\n
Nm Brake<\/div>\n<\/div>\n
\n
63-136<\/div>\n
\u0905\u0928\u0941\u092a\u093e\u0924<\/div>\n<\/div>\n
\n
270 kg<\/div>\n
3-\u0938\u094d\u091f\u0947\u091c<\/div>\n<\/div>\n<\/div>\n
FEM M5<\/span>
\n3,500 RPM<\/span>
\n95% Eff.<\/span><\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\n

406BW3 Winch Drive Planetary Gearbox \u2014 Technical Parameters<\/h2>\n
\n\n\n\n\n\n\n\n\n\n\n\n\n\n
\u0930\u0947\u091f\u0947\u0921 \u0906\u0909\u091f\u092a\u0941\u091f \u091f\u0949\u0930\u094d\u0915<\/td>\n17,500 Nm<\/td>\n<\/tr>\n
Gear ratio range<\/td>\n63 to 136 (three-stage planetary)<\/td>\n<\/tr>\n
Maximum input speed<\/td>\n3,500 rpm<\/td>\n<\/tr>\n
Maximum output speed<\/td>\n25 rpm (FEM M5 continuous duty)<\/td>\n<\/tr>\n
Mechanical efficiency<\/td>\n\u2265 95%<\/td>\n<\/tr>\n
Parking brake<\/td>\n430 Nm, multi-disc, spring-applied, hydraulic release<\/td>\n<\/tr>\n
Brake at drum (ratio-dependent)<\/td>\n27,090 Nm (r=63) to 58,480 Nm (r=136)<\/td>\n<\/tr>\n
Mounting<\/td>\nRotating housing flanges<\/td>\n<\/tr>\n
Dry weight<\/td>\nApprox. 270 kg<\/td>\n<\/tr>\n
\u0938\u094d\u0928\u0947\u0939\u0928<\/td>\nOil bath splash, EP gear oil<\/td>\n<\/tr>\n
\u092a\u0930\u093f\u091a\u093e\u0932\u0928 \u0924\u093e\u092a\u092e\u093e\u0928<\/td>\n-20 to +85 deg C<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/section>\n

<\/p>\n

\n

How the Third Stage Delivers 40% More Torque Within the Same Housing Diameter<\/h2>\n

The 406W two-stage design delivers 13,000 Nm. The 406BW3 three-stage design delivers 17,500 Nm. Both use the same housing diameter class. The third stage does not simply multiply more \u2014 it redistributes the internal loading in a way that unlocks torque capacity the two-stage geometry cannot reach.<\/p>\n

\"406BW3<\/p>\n

\n
\n

Lower per-stage torque<\/strong><\/p>\n

In a two-stage design at ratio 100, the first stage carries approximately ratio 10 and the second carries ratio 10 \u2014 the first stage sees the full 13,000 Nm divided by 10 = 1,300 Nm at the sun gear. In a three-stage design at the same total ratio 100, each stage contributes approximately ratio 4.6 \u2014 the first stage sees 17,500 \/ 4.6 = 3,804 Nm spread across a wider gear face at lower tooth stress. The three-stage distribution allows higher total torque without exceeding the tooth bending limit of any individual stage.<\/p>\n<\/div>\n

\n

Lower bearing radial loads<\/strong><\/p>\n

Each planetary stage generates radial loads on the output bearing proportional to the tangential gear forces. With three stages distributing the total ratio, the tangential forces per stage are lower \u2014 reducing the radial bearing loads by approximately 25-35% compared to a two-stage design at the same total torque. This extends bearing L10 life and allows the 406BW3 to sustain the repeated shock loads of grab crane duty without premature bearing fatigue.<\/p>\n<\/div>\n

\n

Greater thermal mass<\/strong><\/p>\n

The three-stage gear train contains 50% more steel mass than the two-stage equivalent \u2014 9 planet gears instead of 6, 3 sun gears instead of 2, 3 carriers instead of 2. This additional mass absorbs and distributes heat during high-duty-cycle operation, slowing the oil temperature rise during sustained grab crane cycling. The 270 kg total weight is not wasted \u2014 it is thermal capacity that keeps the oil below the 85 deg C limit during the most demanding operations the 406 housing can support.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\n

The Grab Crane Duty Cycle \u2014 Why 17,500 Nm Is the Right Number<\/h2>\n

Grab cranes do not lift and lower \u2014 they slam, tear, grab, and jerk. The torque profile of a grab crane hoist cycle is fundamentally different from a general cargo crane, and the 406BW3 exists because the 406W cannot survive this profile at production duty rates.<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n
Cycle Phase<\/th>\n\u0905\u0935\u0927\u093f<\/th>\nTorque Character<\/th>\nPeak \/ Rated<\/th>\n<\/tr>\n<\/thead>\n
Free-fall drop<\/td>\n3-5 sec<\/td>\nZero (gravity-driven)<\/td>\n0%<\/td>\n<\/tr>\n
Grab impact and closure<\/td>\n1-3 sec<\/td>\nExtreme shock spike<\/td>\n180-250%<\/td>\n<\/tr>\n
Loaded hoist<\/td>\n10-25 sec<\/td>\nSustained high load<\/td>\n80-100%<\/td>\n<\/tr>\n
Slew to discharge<\/td>\n5-10 sec<\/td>\nModerate (holding)<\/td>\n40-60%<\/td>\n<\/tr>\n
Open and dump<\/td>\n2-4 sec<\/td>\nReversal spike<\/td>\n50-80%<\/td>\n<\/tr>\n
Return swing + lower<\/td>\n8-15 sec<\/td>\nLight (empty grab weight)<\/td>\n15-25%<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
The critical moment: <\/span>
\nWhen the grab strikes the bulk pile and begins closing, the hoist cable goes from slack to maximum tension in under one second. This produces a torque spike of 180-250% of rated continuous load. The 406W at 13,000 Nm would see spikes of 23,400-32,500 Nm \u2014 well beyond its 2x peak capacity of 26,000 Nm. The 406BW3 at 17,500 Nm absorbs the same grab impact within its 2x peak capacity of 35,000 Nm, keeping the transient within the safe operating envelope.<\/span><\/div>\n<\/section>\n

<\/p>\n

\n

17,500 Nm \u2014 The Winch Drive for Machines That Slam, Tear, and Grab<\/h2>\n

\"406BW3<\/p>\n

\n
\n

Hydraulic Grab and Clamshell Cranes<\/h3>\n

Harbour cranes handling coal, iron ore, grain, and woodchips with 5-12 m\u00b3 hydraulic grabs at cycle rates of 15-30 per hour. The 406BW3 at ratio 80-110 provides the torque to hoist a loaded grab (8-15 tonnes including grab weight) at 10-18 m\/min while absorbing the 250% shock spikes during grab impact. The slewing drive<\/a> rotates the crane between the ship hold and the hopper, and the wheel drive<\/a> repositions the crane along the quay.<\/p>\n<\/div>\n

\n

Scrap Yard Magnet and Grapple Cranes<\/h3>\n

Overhead cranes and mobile cranes handling ferrous scrap with electromagnets or hydraulic grapples at 20-40 cycles per hour. The scrap handling duty produces torque reversals (magnet engages, load jerks off the pile, cable snaps taut) that are more violent than grab crane impacts because the load engagement is less predictable \u2014 a tangled steel beam separating from a scrap pile generates shock loads that defy calculation. The 406BW3 17,500 Nm with 2x peak headroom provides the margin these unpredictable loads demand.<\/p>\n<\/div>\n

\n

Dredger Bucket Hoists<\/h3>\n

Clamshell and grab dredgers excavating river silt, harbour mud, and marine sediment with 3-8 m\u00b3 buckets. The dredging cycle is slower than harbour crane grab work (8-15 cycles per hour) but the individual shock loads are more severe because the bucket penetrates the seabed under gravity and then tears material loose during closure. The 406BW3 at ratio 100-136 provides both the torque for loaded hoist through water and the shock absorption for bucket impact at the excavation interface<\/a>.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\n

The 406 Family and Beyond<\/h2>\n
\n
\n

\"Winch<\/p>\n

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Full Winch Drive Range \u2192<\/a><\/h3>\n

407AW (18,000 Nm) and 407W3 (26,000 Nm) for applications exceeding the 406BW3 torque capacity.<\/p>\n<\/div>\n<\/div>\n

\n

\"Slewing<\/p>\n

\n

Slewing Drive Planetary Gearbox \u2192<\/a><\/h3>\n

ZR series for grab crane and harbour crane rotation on the same bulk handling platforms.<\/p>\n<\/div>\n<\/div>\n

\n

\"Wheel<\/p>\n

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Wheel Drive Planetary Gearbox \u2192<\/a><\/h3>\n

EP 6xx series for harbour crane gantry travel and mobile grab crane carrier propulsion.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\n

Winch Drive Planetary Gearbox \u2014 Heavy-Duty Grab Crane FAQ<\/h2>\n
\n
\n

Why not use the 407AW (18,000 Nm) instead of the 406BW3 (17,500 Nm)?<\/h3>\n

The 407AW delivers 500 Nm more torque but uses a larger housing frame \u2014 which may not fit inside the existing drum design. The 406BW3 achieves 17,500 Nm within the 406 housing diameter, making it a direct upgrade path for crane OEMs who already have drums and frames designed around the 406 family dimensions. If the drum housing can accommodate the larger 407 frame, the 407AW at 18,000 Nm provides slightly more headroom. If the drum is fixed, the 406BW3 delivers the maximum available torque from the 406 housing.<\/p>\n<\/div>\n

\n

How does the 406BW3 handle the free-fall phase of the grab cycle?<\/h3>\n

During free-fall, the brake is released and the motor is decoupled (or set to free-wheel through a check valve). The grab descends under gravity and the drum accelerates. The gearbox input shaft is driven by the drum through the gear train in reverse (back-driving). At ratio 100, the input shaft reaches approximately 2,500 rpm during free-fall \u2014 within the 3,500 rpm input limit. The motor must be capable of sustaining this over-speed without damage. At the bottom of the free-fall, the brake re-engages to stop the drum before the grab strikes the pile \u2014 or the counterbalance valve catches the motor to control the final approach speed.<\/p>\n<\/div>\n

\n

What overhaul interval applies to a grab crane at 25 cycles per hour?<\/h3>\n

At 25 cycles\/hour, 16 hours\/day, 300 days\/year: approximately 120,000 cycles per year. At FEM M5, the 406BW3 is rated for approximately 1,000,000 total cycles. At this rate, the design life is reached in approximately 8.3 years (approximately 40,000 operating hours). Target first overhaul at 15,000-18,000 hours with oil sampling every 500 hours and brake inspection every 2,000 hours. For higher cycle rates, derate to FEM M6 and reduce the overhaul interval accordingly.<\/p>\n<\/div>\n

\n

Does the 430 Nm brake wear faster on a grab crane than on a general cargo crane?<\/h3>\n

Significantly faster. A general cargo crane engages the brake 50-200 times per day with the drum nearly stationary (parking brake function). A grab crane may engage the brake 200-400 times per day with the drum rotating at speed (free-fall arrest). Each dynamic engagement produces friction heat and disc wear that a static engagement does not. Reduce the brake disc inspection interval to 1,500 hours for grab crane duty (versus 2,500 hours for general cargo). Expect brake disc replacement at 8,000-12,000 hours versus 15,000-25,000 hours on general cargo duty.<\/p>\n<\/div>\n

\n

Can the 406BW3 share brake components with the 406AW and 406W?<\/h3>\n

Yes. All three 406 models use the same 430 Nm brake assembly \u2014 identical disc stack, identical Belleville spring pack, identical piston and rotary union. This is a deliberate design decision: a grab crane fleet operator running both 406BW3 (hoist) and 406W (auxiliary hoist) on the same crane can stock one brake parts kit for both winch drives. The gear sets are model-specific, but the brake, seals, and rotary union are interchangeable across the entire 406 family.<\/p>\n<\/div>\n

\n

What oil change interval applies to the 406BW3 in grab crane service?<\/h3>\n

Every 1,500 hours \u2014 reduced from the 2,000-hour interval for general cargo duty. Grab crane operation generates higher peak oil temperatures due to the frequent shock loading, and the free-fall phase aerates the oil as the drum accelerates and decelerates rapidly. Aerated oil loses lubricity and thermal capacity. Use API GL-5 SAE 80W-90 with anti-foam additives. Oil sampling every 500 hours is mandatory for grab crane duty \u2014 monitor iron particle counts, water content, and viscosity. Contact \u0915\u094b\u0930\u093f\u092f\u093e \u090f\u0935\u0930-\u092a\u093e\u0935\u0930<\/a> for the grab-specific oil recommendation.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\n

Field Reports<\/h2>\n
\n
\n
\n
\u091f\u0940<\/div>\n
\n
Tomasz W. \u2014 Bulk Terminal Crane Engineer<\/div>\n
Verified Purchase \u00b7 Gdansk, Poland \u00b7 April 2026<\/div>\n<\/div>\n
\u2605\u2605\u2605\u2605\u2605<\/div>\n<\/div>\n

Coal handling grab crane, 10 t grab capacity, 22 cycles per hour, 16 hours per day. The 406BW3 at ratio 85 replaced a 406W that was showing bearing distress at 9,000 hours \u2014 the shock loading during grab closure was exceeding the 406W peak capacity 6-8 times per hour. The 406BW3 has completed 7,500 hours of identical duty with oil analysis trending clean and no vibration increase. The 40% torque headroom turned a survival situation into a comfortable operating margin. Brake disc replacement at 10,500 hours \u2014 slightly ahead of the 12,000-hour target, consistent with our cycle rate. Same brake kit as the 406W units on our auxiliary hoists.<\/p>\n<\/div>\n

\n
\n
\u0915\u094d\u092f\u0942<\/div>\n
\n
Qiang Z. \u2014 Scrap Yard Operations Manager<\/div>\n
Verified Purchase<\/div>\n<\/div>\n
\u2605\u2605\u2605\u2605\u2605<\/div>\n<\/div>\n

Overhead magnet crane in a ferrous scrap processing yard. The 406BW3 at ratio 100 handles a 4-tonne electromagnet lifting unpredictable loads \u2014 sometimes a single 3-tonne beam tears free, sometimes a tangled mass of 800 kg separates in stages. The torque spikes from beam separation are brutal and unmeasurable in advance. After 11 months of 3-shift operation, the gearbox has not complained. Our previous supplier drive (rated at 14,000 Nm) lasted 7 months before the first-stage sun gear failed from repeated overload. The 17,500 Nm of the 406BW3 absorbs what the scrap pile throws at it.<\/p>\n<\/div>\n

\n
\n
G<\/div>\n
\n
Gerard M. \u2014 Dredging Fleet Superintendent<\/div>\n
Verified Purchase \u00b7 May 2026<\/div>\n<\/div>\n
\u2605\u2605\u2605\u2605\u2606<\/div>\n<\/div>\n

Clamshell dredger, 6 m\u00b3 bucket, 12 cycles per hour. The 406BW3 at ratio 120 handles the bucket impact and loaded hoist through 8 metres of water at 6 m\/min. Performance is solid and the three-stage gear noise is acceptable in the dredger engine room environment. The 4-star is a thermal observation: during sustained summer operation (35 deg C ambient, 12-hour shifts), the oil temperature reaches 78 deg C \u2014 close to the 85 deg C limit. We installed an external oil cooler with a thermostat bypass, which capped the temperature at 65 deg C. For grab and dredger applications in hot climates, the 406BW3 product specification should include a thermal power derating chart or a recommendation for external cooling above 30 deg C ambient.<\/p>\n<\/div>\n<\/div>\n<\/section>\n<\/div>","protected":false},"excerpt":{"rendered":"

The EP-406BW3 is the three-stage heavy-duty variant that pushes the 406 winch drive planetary gearbox family from 13,000 Nm to 17,500 Nm \u2014 enough for the brutal duty cycles that grab cranes, clamshell dredgers, and scrap yard magnets impose on their hoist mechanisms. The narrow 63-136 ratio range is not a limitation: it is a declaration that this gearbox serves machines whose operating speed is defined by the grab cycle, not by a general cargo handling specification. Every ratio point in the 406BW3 window produces the slow-to-moderate hoist speeds (8-20 m\/min) that grab crane operations demand \u2014 fast enough for productive cycle rates, slow enough for controlled grab closure and load stabilisation.<\/div>","protected":false},"featured_media":948,"comment_status":"open","ping_status":"closed","template":"","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":""},"product_brand":[],"product_cat":[969],"product_tag":[],"class_list":["post-937","product","type-product","status-publish","has-post-thumbnail","product_cat-winch-drive-planetary-gearbox","first","instock","shipping-taxable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/planetary-gearboxes.com\/hi\/wp-json\/wp\/v2\/product\/937","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/planetary-gearboxes.com\/hi\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/planetary-gearboxes.com\/hi\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/hi\/wp-json\/wp\/v2\/comments?post=937"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/hi\/wp-json\/wp\/v2\/media\/948"}],"wp:attachment":[{"href":"https:\/\/planetary-gearboxes.com\/hi\/wp-json\/wp\/v2\/media?parent=937"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/hi\/wp-json\/wp\/v2\/product_brand?post=937"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/hi\/wp-json\/wp\/v2\/product_cat?post=937"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/hi\/wp-json\/wp\/v2\/product_tag?post=937"}],"curies":[{"name":"\u0921\u092c\u094d\u0932\u094d\u092f\u0942\u092a\u0940","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}