{"id":586,"date":"2026-05-28T03:31:46","date_gmt":"2026-05-28T03:31:46","guid":{"rendered":"https:\/\/planetary-gearboxes.com\/?post_type=product&p=586"},"modified":"2026-05-28T03:42:15","modified_gmt":"2026-05-28T03:42:15","slug":"ep-ad-round-flange-inline-planetary-gearbox","status":"publish","type":"product","link":"https:\/\/planetary-gearboxes.com\/nl\/product\/ep-ad-round-flange-inline-planetary-gearbox\/","title":{"rendered":"EP-AD-serie ronde, cirkelvormige flens, uiterst nauwkeurige inline planetaire tandwielkast (EP-AD047 tot EP-AD255)"},"content":{"rendered":"

<\/main><\/p>\n
\n

EP-AD Series \u2014 Round Circular Flange High-Precision Inline Planetary Gearbox<\/h2>\n
\n
\n

\"EP-AD<\/p>\n

\n
\n
Round
\nFlange<\/div>\n
Self-Centring Install<\/div>\n<\/div>\n
\n
\u22641′<\/div>\n
Backlash P0 (arcmin)<\/div>\n<\/div>\n
\n
\u226597%<\/div>\n
Single-Stage Efficiency<\/div>\n<\/div>\n
\n
21\u00b731
\n61\u00b791<\/div>\n
Unique Ratios Available<\/div>\n<\/div>\n<\/div>\n

\n\u2190 Browse All Planetary Gearbox Series
\n<\/a><\/div>\n<\/div>\n
\n

The EP-AD series high-precision planetary gearbox<\/strong> is Korea Ever-Power’s round circular-flange precision variant, addressing the specific installation requirements of rotary tables, hollow-shaft actuators, and circular bearing housings where a square flange introduces eccentric offset and misalignment risk. The circular output flange outer diameter acts as a precision machined datum<\/strong> \u2014 the flange pilots directly into the mating bore, centring the gearbox output shaft concentrically without dial indicator measurement or shimming. This self-centring property reduces installation time and eliminates the most common source of positioning drift in rotary table and turret applications: flange-interface eccentricity.<\/p>\n

Beyond the flange geometry, EP-AD offers a gear ratio set that is unique in the Korea Ever-Power inline range<\/strong>: two-stage configurations include 21, 31, 61, and 91 \u2014 intermediate ratio values not available in the EP-AB square-flange series. These ratios allow engineers to reach specific output speeds from standard 1,450 rpm and 1,500 rpm 4-pole induction motor speeds without requiring a VFD, or to achieve precise speed matching in synchronised multi-axis systems where output RPM must match a defined process rate exactly. Performance of this high-precision planetary gearbox \u2014 P0 \u22641 arcmin backlash, \u226597% single-stage efficiency, \u221210 \u00b0C to +90 \u00b0C, IP65 \u2014 is identical to the EP-AB series.<\/p>\n

\n
\n
\u2b55 Circular Datum Flange<\/div>\n
Pilots into bore \u2014 self-centres without alignment tools.<\/div>\n<\/div>\n
\n
\ud83d\udd22 Unique Ratios 21\/31\/61\/91<\/div>\n
Intermediate two-stage ratios not in any other EP inline series.<\/div>\n<\/div>\n
\n
\ud83d\udd04 Any Install Angle<\/div>\n
Circular flange rotates to any bolt-circle angle \u2014 not limited to 90\u00b0 steps.<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\n

Round vs Square Flange \u2014 The Engineering Case for EP-AD<\/h2>\n
\n

<\/p>\n

\n
\n

SQUARE FLANGE (EP-AB)<\/p>\n

\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510
\n\u2502 \u2022 \u2022 \u2502 \u2190 4 corner bolts
\n\u2502 \u2502
\n\u2502 Output \u2502
\n\u2502 Shaft \u2502
\n\u2502 \u25cb \u2502
\n\u2502 \u2502
\n\u2502 \u2022 \u2022 \u2502
\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518
\nMounting: 4 fixed
\norientation steps (90\u00b0)
\nCentring: relies on
\nbolt tightening<\/div>\n

ROUND FLANGE (EP-AD)<\/p>\n

\u00b7 \u00b7 \u00b7
\n\u00b7 \u2554\u2550\u2550\u2550\u2557 \u00b7
\n\u00b7 \u2551 \u25cb \u2551 \u00b7 \u2190 Output shaft
\n\u00b7 \u255a\u2550\u2550\u2550\u255d \u00b7 centred by
\n\u00b7 \u00b7 \u00b7 bore pilot
\nMounting: any
\nangular position
\nCentring: flange OD
\npilots into bore<\/div>\n<\/div>\n<\/div>\n

<\/p>\n

\n

Four Structural Advantages of the Circular Flange<\/h3>\n
\n
\n

\u2460 Pilots Into the Bore \u2014 Zero Eccentricity Setup<\/strong><\/p>\n

The circular flange OD is machined as a precision diameter that locates directly inside the mating bore of the rotary table, actuator housing, or bearing seat. The gearbox output shaft axis is automatically aligned with the bore axis \u2014 no dial indicator, no shimming, no iterative adjustment. This is the same principle used for motor B5 flanges and bearing housing fits: the machined circular surface does the alignment work, not the installation technician.<\/p>\n<\/div>\n

\n

\u2461 Any Angular Installation Position<\/strong><\/p>\n

A square flange can only be installed at four orientations \u2014 0\u00b0, 90\u00b0, 180\u00b0, 270\u00b0 \u2014 because the corner bolt pattern has four-fold symmetry. The circular bolt-circle of EP-AD has no such constraint: the gearbox can be rotated to any angular position before tightening. For rotary table and turret designs where the cable exit or motor orientation must align precisely with machine structure features, this is a significant layout freedom advantage.<\/p>\n<\/div>\n

\n

\u2462 More Uniform Bolt-Load Distribution<\/strong><\/p>\n

Circular bolt-circles typically carry more bolts than square flanges of equivalent output shaft size, evenly distributed around the circumference. Under the cyclic torsional loading of a servo axis, the torque reaction at the flange is distributed across more fasteners at more uniform angular spacing \u2014 reducing peak bolt tension and the risk of progressive loosening under vibration and direction reversal.<\/p>\n<\/div>\n

\n

\u2463 Geometric Match to Rotationally Symmetric Loads<\/strong><\/p>\n

Rotary tables, indexing chucks, and circular workholding fixtures are themselves rotationally symmetric about the drive axis. The circular flange matches this symmetry \u2014 there is no preferred angular orientation of the load relative to the drive, which means the torque path from gearbox to workholding is geometrically uniform regardless of the rotary position. A square flange on a round table introduces angular asymmetry that must be managed in the machine structural design.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

<\/p>\n

EP-AD vs EP-AB \u2014 Selection Decision Table<\/h3>\n
\n\n\n\n\n\n\n\n\n\n\n\n
Requirement<\/th>\n\u2192 Choose EP-AD \u2605<\/th>\n\u2192 Choose EP-AB<\/th>\n<\/tr>\n<\/thead>\n
Mounting interface geometry<\/td>\nCircular bore, rotary table, hollow-shaft actuator<\/td>\nFlat machine bed, rectangular bolt pattern<\/td>\n<\/tr>\n
Alignment method<\/td>\nSelf-centring via pilot diameter \u2014 no tools needed<\/td>\nBolt tightening; shim if needed<\/td>\n<\/tr>\n
Installation angular freedom<\/td>\nAny angle \u2014 360\u00b0 rotation of gearbox body<\/td>\n4 fixed positions only (0\u00b0\/90\u00b0\/180\u00b0\/270\u00b0)<\/td>\n<\/tr>\n
Required gear ratio<\/td>\ni=21, 31, 61, or 91 needed<\/td>\nStandard ratios only; i=3 or low odd ratios needed<\/td>\n<\/tr>\n
Minimum single-stage ratio<\/td>\ni=4 minimum (no i=3)<\/td>\ni=3 available<\/td>\n<\/tr>\n
Maximum frame size<\/td>\nAD255 (255 mm body \u2014 larger than AB220)<\/td>\nAB220 (220 mm body)<\/td>\n<\/tr>\n
Precision \/ Efficiency \/ IP<\/td>\nIdentical: P0\/P1\/P2 \u00b7 \u226597% single-stage \u00b7 \u221210 to +90 \u00b0C \u00b7 IP65<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
\u25b8 Note on single-stage ratios: <\/span>
\nEP-AD single-stage ratios are 4, 5, 7, and 10 only \u2014 ratios 3, 6, 8, and 9 are not available<\/strong> in this series. If your application requires i=3 (the most common low-ratio servo application), use EP-AB. If you need i=4, 5, 7, or 10 with a circular flange, EP-AD is the correct choice.<\/span><\/div>\n<\/section>\n

<\/p>\n

\n

Unique Ratios 21, 31, 61, 91 \u2014 Why These Intermediate Values Matter<\/h2>\n

As a round flange precision planetary gearbox<\/strong> designed for rotary table and circular actuator installations, the EP-AD two-stage gear ratios include four values \u2014 21, 31, 61, and 91 \u2014 that are absent from the EP-AB square-flange series and from most competing precision planetary gearbox families. These are not arbitrary additions; they reflect real machine design requirements where the available standard ratios (20, 25, 30, 35, 40, 50, 70, 100) do not produce the required output speed from the available motor speed.<\/p>\n

\n

<\/p>\n

\n

Output Speed at Common Motor Inputs \u2014 EP-AD vs Nearest Standard Ratios<\/h3>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Verhouding<\/th>\n1,450 rpm
\n4-pole, 50Hz<\/span><\/th>\n		1,500 rpm
\n4-pole, ideal<\/span><\/th>\n		3,000 rpm
\nservomotor<\/span><\/th>\n		Note<\/th>\n<\/tr>\n<\/thead>\n
i=20<\/td>\n72.5<\/td>\n75.0<\/td>\n150.0<\/td>\nAB\/AD<\/td>\n<\/tr>\n
i=21 \u2605<\/td>\n69.0<\/td>\n71.4<\/td>\n142.9<\/td>\nAD only<\/td>\n<\/tr>\n
i=25<\/td>\n58.0<\/td>\n60.0<\/td>\n120.0<\/td>\nAB\/AD<\/td>\n<\/tr>\n
i=31 (bracket)<\/td>\n\u2014<\/td>\n\u2014<\/td>\n\u2014<\/td>\n<\/td>\n<\/tr>\n
i=31 \u2605<\/td>\n46.8<\/td>\n48.4<\/td>\n96.8<\/td>\nAD only<\/td>\n<\/tr>\n
i=35<\/td>\n41.4<\/td>\n42.9<\/td>\n85.7<\/td>\nAB\/AD<\/td>\n<\/tr>\n
i=50<\/td>\n29.0<\/td>\n30.0<\/td>\n60.0<\/td>\nAB\/AD<\/td>\n<\/tr>\n
i=61 \u2605<\/td>\n23.8<\/td>\n24.6<\/td>\n49.2<\/td>\nAD only<\/td>\n<\/tr>\n
i=70<\/td>\n20.7<\/td>\n21.4<\/td>\n42.9<\/td>\nAB\/AD<\/td>\n<\/tr>\n
i=91 \u2605<\/td>\n15.9<\/td>\n16.5<\/td>\n33.0<\/td>\nAD only<\/td>\n<\/tr>\n
i=100<\/td>\n14.5<\/td>\n15.0<\/td>\n30.0<\/td>\nAB\/AD<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

<\/p>\n

\n

When the Intermediate Ratio Solves a Real Problem<\/h3>\n
\n
\n

i=21 \u2014 Speed Between 20 and 25<\/strong><\/p>\n

When an induction motor at 1,500 rpm must drive an output at exactly 70\u201372 rpm \u2014 between what i=20 (75 rpm) and i=25 (60 rpm) give \u2014 i=21 yields 71.4 rpm. Without this ratio, the engineer must either accept a 5% speed error or add a VFD to trim the motor speed. For synchronised conveyors or process lines where output speed must match product rate exactly, this eliminates the VFD cost and its associated energy losses.<\/p>\n<\/div>\n

\n

i=61 \u2014 Bridging 50 and 70<\/strong><\/p>\n

i=61 at 1,500 rpm input gives 24.6 rpm output \u2014 a speed required by many slow-running precision turntables and rotary welding fixtures. i=50 gives 30 rpm (too fast) and i=70 gives 21.4 rpm (too slow). i=61 lands exactly in this gap. The 20 rpm range between i=50 and i=70 is a particularly common requirement for Korean robotics and welding automation equipment.<\/p>\n<\/div>\n

\n

i=91 \u2014 Near 16 rpm Without a VFD<\/strong><\/p>\n

At 1,500 rpm input, i=91 yields 16.5 rpm \u2014 close enough to 16 rpm (a common slow-process speed) that a standard induction motor drives the output without requiring variable speed control. i=100 gives only 15 rpm; i=91 adds 10% more speed while still being achievable as a two-stage gear ratio in a compact planetary form factor.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\n

EP-AD047 to EP-AD255 \u2014 Complete Round Flange Planetary Gearbox Specifications<\/h2>\n
\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Common Specifications \u2014 All EP-AD Frames<\/th>\n<\/tr>\n<\/thead>\n
Output Torque Range (T2N)<\/td>\n14 N\u00b7m (EP-AD047) to 2,000 N\u00b7m (EP-AD255)<\/td>\n<\/tr>\n
Output Flange<\/td>\nRound circular flange with precision pilot diameter for bore self-centring<\/td>\n<\/tr>\n
Backlash \u2014 P0 (Micro)<\/td>\nSingle-stage \u22641 arcmin \u00b7 Two-stage \u22643 arcmin<\/td>\n<\/tr>\n
Backlash \u2014 P1 (Reduced)<\/td>\nSingle-stage \u22643 arcmin \u00b7 Two-stage \u22645 arcmin<\/td>\n<\/tr>\n
Backlash \u2014 P2 (Standard)<\/td>\nSingle-stage \u22645 arcmin \u00b7 Two-stage \u22647 arcmin<\/td>\n<\/tr>\n
Single-Stage Ratios<\/td>\n4, 5, 7, 10 (note: ratios 3, 6, 8, 9 not available in EP-AD)<\/span><\/td>\n<\/tr>\n
Two-Stage Ratios<\/td>\n16, 20, 21<\/strong>, 25, 31<\/strong>, 35, 40, 50, 61<\/strong>, 70, 91<\/strong>, 100 (\u2605 bold = unique to EP-AD)<\/span><\/td>\n<\/tr>\n
Single-Stage Efficiency<\/td>\n\u226597%<\/td>\n<\/tr>\n
Two-Stage Efficiency<\/td>\n\u226594%<\/td>\n<\/tr>\n
Bedrijfstemperatuur<\/td>\n\u221210 \u00b0C to +90 \u00b0C (with series grease)<\/td>\n<\/tr>\n
Protection Rating<\/td>\nIP65 standard \u00b7 IP67 optional<\/td>\n<\/tr>\n
Output Shaft<\/td>\nS1: smooth cylindrical shaft \u00b7 S2: with keyway<\/td>\n<\/tr>\n
Smering<\/td>\nSealed grease \u2014 maintenance-free under normal conditions<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

<\/p>\n

Available Frame Sizes \u2014 EP-AD047 Through EP-AD255<\/h3>\n
\n\n\n\n\n\n\n
Frame<\/th>\nAD047<\/th>\nAD064<\/th>\nAD090<\/th>\nAD110<\/th>\nAD140<\/th>\nAD200<\/th>\nAD255<\/th>\n<\/tr>\n<\/thead>\n
Body \u00d8 (mm)<\/td>\n47<\/td>\n64<\/td>\n90 \u2605<\/td>\n110<\/td>\n140<\/td>\n200<\/td>\n255<\/td>\n<\/tr>\n
Torque class<\/td>\nMin (14 N\u00b7m)<\/td>\nLight<\/td>\nMost specified<\/td>\nMedium<\/td>\nMed-heavy<\/td>\nHeavy<\/td>\nMax (2,000 N\u00b7m)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Note: EP-AD frame numbers (047, 064, 110, 140, 200, 255) differ from EP-AB frame numbers \u2014 the two series are not dimensionally interchangeable despite similar torque ranges. Always verify dimensional drawings before substituting AD for AB or vice versa. For applications requiring a wider output flange for overturning moment resistance or IP67 submersion protection, see the EP-AE large flange planetary gearbox<\/a>.<\/p>\n<\/section>\n

<\/p>\n

\n

Model Designation Guide \u2014 EP-AD Part Number<\/h2>\n
\n
EP-AD 090 \/ 61 \/ S2 \/ P1<\/div>\n
\n
\n
EP-AD<\/div>\n
Korea Ever-Power
\nInline, Round Flange
\nPrecision Series<\/div>\n<\/div>\n
\n
090<\/div>\n
Housing body
\ndiameter: 90 mm<\/div>\n<\/div>\n
\n
61<\/div>\n
Gear ratio i=61:1
\n(two-stage)
\nEP-AD exclusive ratio<\/div>\n<\/div>\n
\n
S2<\/div>\n
Output shaft
\nS1: smooth
\nS2: with keyway<\/div>\n<\/div>\n
\n
P1<\/div>\n
Backlash grade
\nP0 \/ P1 \/ P2<\/div>\n<\/div>\n<\/div>\n<\/div>\n
\n\n\n\n\n\n\n\n\n\n
Position<\/th>\nCode<\/th>\nOptions \/ Meaning<\/th>\n<\/tr>\n<\/thead>\n
Series<\/td>\nEP-AD<\/td>\nKorea Ever-Power inline round circular-flange precision planetary gearbox. No “A” suffix variant \u2014 input configuration handled via motor adapter plate selection<\/td>\n<\/tr>\n
Frame Size<\/td>\n047 \/ 064 \/ 090 \/ 110 \/ 140 \/ 200 \/ 255<\/td>\nHousing body diameter in mm. Different scale from EP-AB<\/strong> \u2014 do not assume physical interchangeability between AD and AB of the same number.<\/td>\n<\/tr>\n
Gear Ratio<\/td>\n4\/5\/7\/10 \u00b7 16\u2013100 (incl. 21\/31\/61\/91)<\/td>\nSingle-stage: 4, 5, 7, 10 only (no 3, 6, 8, 9) \u00b7 Two-stage: 16, 20, 21, 25, 31, 35, 40, 50, 61, 70, 91, 100<\/td>\n<\/tr>\n
Output Shaft<\/td>\nS1 \/ S2<\/td>\nS1: smooth \u00b7 S2: with keyway<\/td>\n<\/tr>\n
Backlash Grade<\/td>\nP0 \/ P1 \/ P2<\/td>\nP0: \u22641’\/\u22643′ \u00b7 P1: \u22643’\/\u22645′ \u00b7 P2: \u22645’\/\u22647′ (single\/two-stage)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/section>\n

<\/p>\n

\n

Applications \u2014 Circular Flange Mounting and Precise Output Speed Requirements<\/h2>\n
\n
\n
\n

Precision Rotary Tables \u2014 Round Bore, Self-Centring P1<\/h3>\n

Korean precision rotary tables for CNC machining centres are designed with a circular drive bore at the table base \u2014 a bore that accepts the round flange of EP-AD directly. The pilot diameter self-centres the gearbox output shaft with the table rotation axis to within manufacturing tolerance, eliminating the eccentricity that would cause table wobble under cutting loads. The 090 and 110 frames at P1 (\u22643 arcmin) at ratios 20\u201361 cover the majority of Korean 4th-axis precision rotary table drives, including the intermediate ratio i=61 for tables that must run at approximately 24 rpm from a standard 1,450 rpm motor. Compatible with precision CV drive shafts for dual-motor rotary table configurations.<\/p>\n<\/div>\n

\n

Automatic Welding Positioners \u2014 Round Flange, Any Angle<\/h3>\n

Welding positioner frames are built around rotational symmetry \u2014 the drive must be concentric with the workpiece rotation axis with no eccentricity that would cause weld path deviation. EP-AD’s circular flange pilots directly into the positioner drive housing bore, centring the gearbox without alignment adjustment. For Korean automated welding cells that must run at 15\u201370 rpm positioner speed \u2014 the speed range of most MIG and TIG rotary welding applications \u2014 the EP-AD ratio set’s unique values (particularly i=21 and i=61) reach specific weld speeds directly from standard motor speeds, synchronising positioner rotation with wire feed and travel speed without introducing a separate VFD that could create noise interference with the welding controller.<\/p>\n<\/div>\n

\n

Hollow-Shaft Rotary Actuators \u2014 Circular Housing, P0 Grade<\/h3>\n

Rotary actuators for Korean collaborative robots, semiconductor handling, and optical positioning systems are often designed with hollow-shaft output geometry \u2014 cables and utilities pass through the rotation axis. These actuators have circular inner bore housings that match EP-AD’s round flange directly. At P0 (\u22641 arcmin), the The 047 and 064 frames serve the sub-arcminute precision requirement of optical alignment and semiconductor positioning actuators, where the round flange’s self-centring property also ensures that the hollow-shaft bore concentricity is maintained after each maintenance reassembly.<\/p>\n<\/div>\n<\/div>\n

\n
\n

Application Reference<\/h3>\n