{"id":1938,"date":"2026-10-08T06:35:46","date_gmt":"2026-10-08T06:35:46","guid":{"rendered":"https:\/\/metalite.net\/?p=1938"},"modified":"2026-10-08T06:46:21","modified_gmt":"2026-10-08T06:46:21","slug":"wp-series-worm-gearbox-model-codes-frame-sizes-torque-ratings","status":"publish","type":"post","link":"https:\/\/metalite.net\/hi\/application\/wp-series-worm-gearbox-model-codes-frame-sizes-torque-ratings\/","title":{"rendered":"WP Series Worm Gearbox: Model Codes, Frame Sizes & Torque Ratings"},"content":{"rendered":"
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The WP Series worm gearbox is EPG Canada’s heavy-duty cast iron worm reducer line \u2014 built for sustained high-torque operation in demanding plant environments where duty cycles are long, shock loads are common, and replacement downtime is expensive. Unlike compact aluminum-housing reducers optimized for light-to-medium duty, the WP Series is engineered to absorb vibration, handle overloads, and run continuously across a full range of frame sizes from 40 to 250.<\/p>\n

This page covers WP Series model codes, frame sizes, torque and power ratings, standard gear ratios, material specifications, and mounting configurations. For application-specific guidance on conveyors, mining equipment, and industrial drives, see our WP Worm Gearbox Industrial Applications guide<\/a>.<\/p>\n

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WP Series Model Codes: Understanding the Designation System<\/h2>\n
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\"WP<\/p>\n

WP Series cast iron worm gearbox \u2014 multiple sub-models cover every mounting and shaft configuration<\/p>\n<\/div>\n

The WP designation covers a matrix of sub-models, each engineered for a specific mounting geometry or shaft configuration. Understanding the model code structure allows procurement teams to specify the exact unit needed without ambiguity:<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n\n
Model Code<\/th>\nFull Name<\/th>\nMounting \/ Shaft Configuration<\/th>\nTypical Use<\/th>\n<\/tr>\n<\/thead>\n
WPA<\/td>\nWP Standard \u2014 Foot Mounted<\/td>\nFoot (base-plate) mounted; single solid output shaft; hollow input for motor coupling<\/td>\nFloor-mounted drives; most common WP variant<\/td>\n<\/tr>\n
WPS<\/td>\nWP Solid Input Shaft<\/td>\nFoot mounted; solid projecting input shaft for chain, belt, or direct coupling<\/td>\nBelt-input and chain-drive arrangements; non-motor inputs<\/td>\n<\/tr>\n
WPDA<\/td>\nWP Double Output Shaft<\/td>\nFoot mounted; output shafts on both sides of the housing; hollow motor input<\/td>\nDriving two separate loads from one gearbox; symmetrical conveyor drives<\/td>\n<\/tr>\n
WPDS<\/td>\nWP Double Shaft \u2014 Solid Input<\/td>\nFoot mounted; double output shafts; solid projecting input shaft<\/td>\nTwin-output drives with non-standard motor input (e.g., hydraulic motor)<\/td>\n<\/tr>\n
WPO<\/td>\nWP Hollow Output Bore<\/td>\nFoot mounted; hollow bore on the output for direct shaft mounting; eliminates coupling<\/td>\nShaft-mounted conveyor and agitator drives; space-saving installations<\/td>\n<\/tr>\n
WPWKO<\/td>\nWP Overhead \/ Suspended<\/td>\nFlange or bracket mounting for overhead \/ suspended installation; hollow output<\/td>\nOverhead conveyor drives; elevated agitator drives; crane auxiliary drives<\/td>\n<\/tr>\n
WPX<\/td>\nWP Extended Housing<\/td>\nExtended housing to accommodate longer shaft or wider bearing span for high overhung loads<\/td>\nHigh overhung-load applications; screw and auger drives with extended shaft<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
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Model code example:<\/strong> WPDA-80-40:1<\/em> denotes a WP Series, double-output-shaft gearbox (WPDA), frame size 80, ratio 40:1. When ordering, also specify the motor frame size and mounting orientation so the correct motor adapter and oil-fill position are confirmed before shipment.<\/p>\n<\/div>\n

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WP Series Frame Sizes, Torque and Power Ratings<\/h2>\n

The frame size number indicates the worm center distance in millimetres. The WP Series spans 12 frame sizes from 40 to 250, covering input powers from 0.12 kW to 35 kW and output torques up to 4,500 Nm \u2014 one of the broadest single-series worm gearbox ranges available from a single source.<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Frame Size<\/th>\nCentre Distance (mm)<\/th>\nMax Output Torque (Nm)<\/th>\nInput Power Range (kW)<\/th>\nOutput Shaft Dia. (mm)<\/th>\n<\/tr>\n<\/thead>\n
40<\/td>\n40<\/td>\n30<\/td>\n0.12 \u2013 0.55<\/td>\n20<\/td>\n<\/tr>\n
50<\/td>\n50<\/td>\n60<\/td>\n0.18 \u2013 0.75<\/td>\n25<\/td>\n<\/tr>\n
60<\/td>\n60<\/td>\n105<\/td>\n0.37 \u2013 1.1<\/td>\n30<\/td>\n<\/tr>\n
70<\/td>\n70<\/td>\n170<\/td>\n0.55 \u2013 1.5<\/td>\n35<\/td>\n<\/tr>\n
80<\/td>\n80<\/td>\n260<\/td>\n0.75 \u2013 2.2<\/td>\n40<\/td>\n<\/tr>\n
100<\/td>\n100<\/td>\n460<\/td>\n1.5 \u2013 4.0<\/td>\n50<\/td>\n<\/tr>\n
120<\/td>\n120<\/td>\n760<\/td>\n2.2 \u2013 7.5<\/td>\n60<\/td>\n<\/tr>\n
135<\/td>\n135<\/td>\n1,050<\/td>\n3.0 \u2013 11<\/td>\n70<\/td>\n<\/tr>\n
155<\/td>\n155<\/td>\n1,580<\/td>\n4.0 \u2013 15<\/td>\n80<\/td>\n<\/tr>\n
175<\/td>\n175<\/td>\n2,150<\/td>\n5.5 \u2013 22<\/td>\n90<\/td>\n<\/tr>\n
200<\/td>\n200<\/td>\n2,850<\/td>\n7.5 \u2013 30<\/td>\n100<\/td>\n<\/tr>\n
250<\/td>\n250<\/td>\n4,500<\/td>\n11 \u2013 35+<\/td>\n120<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

* Max output torque values are at lowest efficiency. Always apply a service factor (SF) before selecting frame size \u2014 typical SF: 1.25 for moderate shock, 1.5\u20132.0 for heavy shock or 24\/7 duty. Contact our team for thermal power ratings on continuous-duty applications.<\/p>\n

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Standard Gear Ratios: Single Stage and Double Stage<\/h2>\n
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Single Stage \u2014 Ratios 5:1 to 100:1<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Ratio<\/th>\nOutput RPM (1,450 in)<\/th>\nEfficiency (approx.)<\/th>\n<\/tr>\n<\/thead>\n
5:1<\/td>\n290<\/td>\n~85\u201390%<\/td>\n<\/tr>\n
10:1<\/td>\n145<\/td>\n~80\u201385%<\/td>\n<\/tr>\n
15:1<\/td>\n97<\/td>\n~77\u201382%<\/td>\n<\/tr>\n
20:1<\/td>\n72<\/td>\n~74\u201380%<\/td>\n<\/tr>\n
30:1<\/td>\n48<\/td>\n~70\u201376%<\/td>\n<\/tr>\n
40:1<\/td>\n36<\/td>\n~68\u201374%<\/td>\n<\/tr>\n
50:1<\/td>\n29<\/td>\n~66\u201372%<\/td>\n<\/tr>\n
60:1<\/td>\n24<\/td>\n~64\u201370%<\/td>\n<\/tr>\n
80:1<\/td>\n18<\/td>\n~62\u201368%<\/td>\n<\/tr>\n
100:1<\/td>\n14.5<\/td>\n~60\u201366%<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
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Double Stage \u2014 Ratios 200:1 to 900:1<\/p>\n\n\n\n\n\n\n\n\n\n
Combined Ratio<\/th>\nStage 1 \u00d7 Stage 2<\/th>\nOutput RPM (1,450 in)<\/th>\n<\/tr>\n<\/thead>\n
200:1<\/td>\n20 \u00d7 10<\/td>\n7.3<\/td>\n<\/tr>\n
300:1<\/td>\n30 \u00d7 10<\/td>\n4.8<\/td>\n<\/tr>\n
400:1<\/td>\n20 \u00d7 20<\/td>\n3.6<\/td>\n<\/tr>\n
600:1<\/td>\n30 \u00d7 20<\/td>\n2.4<\/td>\n<\/tr>\n
900:1<\/td>\n30 \u00d7 30<\/td>\n1.6<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
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Important:<\/strong> Dual-stage WP efficiency is the product of both stages \u2014 at 30\u00d730 (900:1), overall efficiency may be as low as 42\u201349%. Always size the motor for thermal power loss, not just mechanical output torque, when using double-stage configurations.<\/p>\n<\/div>\n<\/div>\n<\/div>\n

* Available ratio steps may vary by frame size. Confirm exact ratio availability for your frame size before ordering. Custom ratios are available through the Non-Standard program.<\/p>\n

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Why Cast Iron Housing: The Technical Case for Heavy-Duty Applications<\/h2>\n
\"WP<\/div>\n

The WP Series uses heavy-duty cast iron (grey iron GG25 \/ HT250 grade) throughout all frame sizes \u2014 not just on larger units. This is a deliberate engineering decision driven by the application profile the WP Series is designed for, not a cost default. Cast iron delivers four specific advantages in sustained high-torque industrial service:<\/p>\n

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Superior Structural Rigidity<\/p>\n

Cast iron’s higher elastic modulus maintains housing geometry under large worm reaction forces, preventing bearing misalignment and premature gear wear on heavily loaded drives.<\/p>\n<\/div>\n

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High Vibration Damping<\/p>\n

Cast iron absorbs vibration energy far more effectively than aluminum. On applications with repeated shock loads \u2014 conveyors starting under load, stone crushers, material handling \u2014 this damping capacity directly extends gear pair and bearing service life.<\/p>\n<\/div>\n

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Thermal Mass for Sustained Duty<\/p>\n

Cast iron’s high thermal mass acts as a heat buffer during sustained continuous operation, smoothing out temperature spikes from load surges before they affect lubricant viscosity and film strength.<\/p>\n<\/div>\n

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Breather Plug & Oil Mirror<\/p>\n

All WP Series units include a breather plug to equalize internal pressure during thermal cycling, and an oil sight glass to allow visual oil level inspection without draining \u2014 reducing maintenance time and the risk of running under-oiled.<\/p>\n<\/div>\n<\/div>\n

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Worm Shaft and Worm Wheel Material Specifications<\/h2>\n
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Worm Shaft (Input)<\/p>\n