{"id":932,"date":"2026-06-18T05:33:46","date_gmt":"2026-06-18T05:33:46","guid":{"rendered":"https:\/\/planetary-gearboxes.com\/?post_type=product&p=932"},"modified":"2026-06-18T05:33:46","modified_gmt":"2026-06-18T05:33:46","slug":"403w2-winch-drive-planetary-gearbox","status":"publish","type":"product","link":"https:\/\/planetary-gearboxes.com\/es\/producto\/403w2-winch-drive-planetary-gearbox\/","title":{"rendered":"Reductor de engranajes planetarios para cabrestante 403W2 \u2014 2 etapas"},"content":{"rendered":"
<\/p>\n Read the 402W2 page. Now read this one. The two products share the same housing diameter, the same two-stage planetary architecture, the same 3,500 rpm input ceiling, the same 4,000 Nm output rating, and the same FEM M5 duty classification. The difference is 5 kg and a set of friction discs.<\/p>\n The 403W2 adds a 270 Nm spring-applied, hydraulically released multi-disc negative brake inside the rotating housing. This brake engages the moment hydraulic pressure drops \u2014 whether by deliberate operator action, emergency shutdown, hose failure, or total system power loss. It holds the drum, the cable, and whatever is hanging on the cable in position, independently of any external component. No motor brake needed. No counterbalance valve needed. The Caja de engranajes planetarios de accionamiento del cabrestante<\/a> itself is the safety system.<\/p>\n <\/p>\n <\/p>\n A brake inside a wheel drive housing sits still. A brake inside a winch drive housing rotates with the drum at up to 25 rpm. This rotating environment creates engineering challenges that a stationary-housing brake never faces.<\/p>\n Centrifugal Oil Management<\/strong><\/p>\n Rotation creates centrifugal force that pushes oil outward toward the housing wall. The brake discs, located near the centre of rotation, must remain adequately lubricated for cooling during dynamic braking but not flooded with oil during static hold \u2014 oil between the discs during static hold would reduce the friction coefficient and degrade the holding torque. The 403W2 uses grooved separator plates that channel oil radially outward during rotation, keeping the disc faces drained during static engagement while allowing oil to reach the discs during dynamic deceleration when cooling is needed.<\/p>\n<\/div>\n Spring Pack Orientation<\/strong><\/p>\n The spring pack that applies the brake must function identically regardless of the drum rotational position. In a stationary housing, gravity always acts in the same direction relative to the springs. In a rotating housing, the spring orientation with respect to gravity changes continuously. The 403W2 uses a Belleville disc spring stack arranged concentrically around the input shaft \u2014 the axial clamping force is symmetric and unaffected by the rotational position. Coil springs, which can shift laterally under centrifugal load, are not used.<\/p>\n<\/div>\n Hydraulic Release in a Rotating Frame<\/strong><\/p>\n The brake release oil must travel from the stationary hydraulic supply line into the rotating housing through a rotary union (swivel joint) at the shaft centre. This rotary union is a wear item \u2014 it seals high-pressure oil (25-40 bar release pressure) against a rotating surface. The 403W2 rotary union uses carbon-graphite sealing rings against hardened steel races, providing 10,000+ hour service life at up to 25 rpm continuous rotation. Inspect the rotary union for external leakage at every 2,500-hour service interval.<\/p>\n<\/div>\n<\/div>\n<\/div>\n <\/p>\n403W2 \u2014 The Braked Twin: 4,000 Nm with 270 Nm Inside the Drum<\/h2>\n
\n270 Nm Brake<\/span>
\nRatios 15.4-40<\/span>
\n3,500 RPM<\/span>
\n120 kg<\/span>
\nFEM M5<\/span><\/div>\n<\/div>\n
<\/div>\n<\/div>\n<\/section>\n403W2 Winch Drive Gearbox \u2014 Technical Parameters<\/h2>\n
\n\n
\n Par de salida nominal<\/td>\n 4,000 Nm<\/td>\n<\/tr>\n \n Rango de relaci\u00f3n de transmisi\u00f3n<\/td>\n 15.4 to 40 (two-stage planetary)<\/td>\n<\/tr>\n \n Velocidad m\u00e1xima de entrada<\/td>\n 3.500 rpm<\/td>\n<\/tr>\n \n Velocidad de salida m\u00e1xima<\/td>\n 25 rpm (FEM M5 de servicio continuo)<\/td>\n<\/tr>\n \n Eficiencia mec\u00e1nica<\/td>\n \u2265 95%<\/td>\n<\/tr>\n \n Integrated parking brake<\/td>\n 270 Nm, multi-disc, spring-applied, hydraulic release<\/td>\n<\/tr>\n \n Brake holding at drum (via ratio)<\/td>\n 4,158 – 10,800 Nm (ratio dependent)<\/td>\n<\/tr>\n \n Montaje<\/td>\n Rotating housing flanges (direct drum integration)<\/td>\n<\/tr>\n \n Peso seco<\/td>\n Approx. 120 kg<\/td>\n<\/tr>\n \n Lubricaci\u00f3n<\/td>\n Oil bath splash, premium EP gear oil<\/td>\n<\/tr>\n \n Temperatura de funcionamiento<\/td>\n -20 to +85 deg C (extreme climate seal kits available)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/section>\n A Brake That Spins \u2014 Multi-Disc Negative Brake Engineering Inside a Rotating Drum<\/h2>\n
<\/div>\n<\/div>\n<\/section>\n402W2 or 403W2 \u2014 What the Brake Costs You and What It Gives Back<\/h2>\n