{"id":713,"date":"2026-06-01T05:48:38","date_gmt":"2026-06-01T05:48:38","guid":{"rendered":"https:\/\/planetary-gearboxes.com\/?p=713"},"modified":"2026-06-01T05:48:38","modified_gmt":"2026-06-01T05:48:38","slug":"planetary-gearbox-radial-axial-load-capacity-calculation","status":"publish","type":"post","link":"https:\/\/planetary-gearboxes.com\/it\/planetary-gearbox-radial-axial-load-capacity-calculation\/","title":{"rendered":"Capacit\u00e0 di carico radiale e assiale del riduttore epicicloidale - Guida al calcolo"},"content":{"rendered":"<div style=\"max-width: 1200px; margin: 0 auto; padding: 0 3% 3rem; font-family: -apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Arial,sans-serif; color: #333; line-height: 1.7;\">\n<p><!-- \u2550\u2550\u2550 HERO \u2550\u2550\u2550 --><\/p>\n<section style=\"position: relative; margin: 0 -3% 4rem; width: calc(100% + 6%); min-height: 360px; display: flex; align-items: center; overflow: hidden; border-radius: 0 0 12px 12px;\"><img decoding=\"async\" style=\"position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; filter: brightness(.3);\" src=\"https:\/\/planetary-gearboxes.com\/wp-content\/uploads\/2026\/05\/BABR-Series-Planetary-Gearbox-1.webp\" alt=\"planetary gearbox radial load capacity calculation bearing L10 life overhang Korea Ever-Power\" title=\"\"><\/p>\n<div style=\"position: relative; z-index: 1; padding: clamp(2rem,5vw,3.5rem) clamp(1.5rem,4vw,3rem); max-width: 860px;\">\n<div style=\"display: inline-block; background: #0277bd; color: #fff; font-size: 12px; font-weight: bold; letter-spacing: 1.5px; padding: .35rem .9rem; border-radius: 20px; margin-bottom: 1rem; text-transform: uppercase;\">Engineering Reference \u00b7 L10 Calculation \u00b7 Overhang Position \u00b7 AF vs AB Comparison<\/div>\n<h1 style=\"font-size: clamp(24px,4vw,42px); font-weight: 800; color: #fff; line-height: 1.25; margin: 0 0 1.1rem; text-shadow: 0 2px 12px rgba(0,0,0,.6);\">Planetary Gearbox Radial Load Capacity \u2014<br \/>\nL10 Bearing Life and Shaft Selection<\/h1>\n<p style=\"font-size: clamp(14px,1.9vw,17px); color: rgba(255,255,255,.92); margin: 0 0 1.6rem; line-height: 1.7; max-width: 720px;\">Correctly specifying planetary gearbox radial load capacity prevents the most common cause of premature planetary gearbox output bearing failure in Korean industry is not under-rated torque \u2014 it is <strong style=\"color: #b3e5fc;\">under-rated radial load<\/strong>. A sprocket, pulley, or pinion mounted on the output shaft imposes a radial force that must be supported by the output bearing system. When this force is applied at a distance from the gearbox face, the bending moment on the output shaft multiplies the effective bearing load \u2014 and L10 bearing life drops with the cube of that load ratio.<\/p>\n<p><a style=\"display: inline-block; background: #0277bd; color: #fff; font-weight: bold; font-size: clamp(13px,1.7vw,15px); padding: .8rem 1.8rem; border-radius: 6px; text-decoration: none; box-shadow: 0 4px 16px rgba(0,0,0,.3);\" href=\"https:\/\/planetary-gearboxes.com\/it\/prodotto\/ep-af-high-rigidity-inline-planetary-gearbox\/\">View EP-AF High-Rigidity Series \u2192<br \/>\n<\/a><\/p>\n<\/div>\n<\/section>\n<p><!-- \u2550\u2550\u2550 MODULE 1: Radial vs Axial Load \u2014 What They Are and Where They Come From \u2550\u2550\u2550 --><\/p>\n<section style=\"margin-bottom: 3.5rem;\">\n<h2 style=\"font-size: clamp(20px,3vw,28px); font-weight: bold; color: #1a1a1a; border-bottom: 3px solid #0277bd; padding-bottom: .75rem; margin: 0 0 1.4rem;\">Radial vs Axial Load \u2014 Sources and Why Both Must Be Calculated<\/h2>\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: #444; margin: 0 0 1.1rem;\">Every planetary gearbox output shaft carries three types of loading simultaneously: torque (the primary drive force), radial load (a force perpendicular to the shaft axis), and axial load (a force along the shaft axis). The torque capacity is what most engineers specify from the catalogue. The radial and axial loads are frequently underestimated or omitted \u2014 and their effect on bearing life is far more severe than the equivalent increase in torque.<\/p>\n<div style=\"display: grid; grid-template-columns: repeat(auto-fit,minmax(260px,1fr)); gap: 1.2rem; margin-bottom: 1.5rem;\">\n<div style=\"background: #fff; border: 1px solid #e0e0e0; border-top: 4px solid #c62828; border-radius: 0 0 8px 8px; padding: 1.1rem 1.2rem;\">\n<h3 style=\"font-size: 14px; font-weight: bold; color: #c62828; margin: 0 0 .6rem;\">Radial load sources<\/h3>\n<p style=\"font-size: 12px; color: #444; line-height: 1.65; margin: 0 0 .7rem;\">A force perpendicular to the output shaft axis \u2014 the key planetary gearbox radial load source. Generated by:<\/p>\n<ul style=\"font-size: 12px; color: #444; margin: 0; padding-left: 1.2rem; line-height: 1.9;\">\n<li><strong>Belt drive:<\/strong> Tight-side + slack-side belt tension resultant. For a flat\/V belt with tension ratio T\u2081\/T\u2082 = 3, the net radial force \u2248 2 \u00d7 T\u2081 \u00d7 cos(wrap angle \/ 2)<\/li>\n<li><strong>Chain drive:<\/strong> Chain tension acts tangentially on the sprocket; the resultant of drive-side and slack-side tensions is the radial load on the gearbox shaft<\/li>\n<li><strong>Rack and pinion:<\/strong> Tangential cutting force on the pinion creates a radial component at the pitch point equal to F_tangential \u00d7 tan(pressure angle)<\/li>\n<li><strong>Gear mesh:<\/strong> Spur gear mesh produces radial force = F_tangential \u00d7 tan(pressure angle)<\/li>\n<\/ul>\n<\/div>\n<div style=\"background: #fff; border: 1px solid #e0e0e0; border-top: 4px solid #0277bd; border-radius: 0 0 8px 8px; padding: 1.1rem 1.2rem;\">\n<h3 style=\"font-size: 14px; font-weight: bold; color: #0277bd; margin: 0 0 .6rem;\">Axial load sources<\/h3>\n<p style=\"font-size: 12px; color: #444; line-height: 1.65; margin: 0 0 .7rem;\">A force along the output shaft axis. Generated by:<\/p>\n<ul style=\"font-size: 12px; color: #444; margin: 0; padding-left: 1.2rem; line-height: 1.9;\">\n<li><strong>Helical gear mesh:<\/strong> The helix angle produces an axial force component = F_tangential \u00d7 tan(helix angle). At 20\u00b0 helix angle: F_axial = 0.36 \u00d7 F_tangential<\/li>\n<li><strong>Helical coupling:<\/strong> Torque-induced axial force proportional to shaft misalignment angle<\/li>\n<li><strong>Thrust from conveyor belt:<\/strong> Belt drive with angular misalignment or crowned pulley creates a lateral (axial) force at the shaft end<\/li>\n<li><strong>Screw conveyor thrust:<\/strong> Material resistance on the screw flighting creates thrust that acts axially on the drive shaft<\/li>\n<\/ul>\n<\/div>\n<div style=\"background: #fff; border: 1px solid #e0e0e0; border-top: 4px solid #1b5e20; border-radius: 0 0 8px 8px; padding: 1.1rem 1.2rem;\">\n<h3 style=\"font-size: 14px; font-weight: bold; color: #1b5e20; margin: 0 0 .6rem;\">Why radial load matters more than torque for bearing life<\/h3>\n<p style=\"font-size: 12px; color: #444; line-height: 1.65; margin: 0 0 .7rem;\">The L10 bearing life relationship is cubic: L10 \u221d (C\/P)\u00b3. Doubling the radial load P reduces bearing life to (1\/2)\u00b3 = one-eighth. The same doubling of <em>coppia<\/em> typically increases bearing load by much less than doubling (because torque loads the gear teeth, not the output bearing directly). This asymmetry means radial load specification errors have a disproportionately severe impact on bearing life.<\/p>\n<\/div>\n<\/div>\n<\/section>\n<p><!-- \u2550\u2550\u2550 MODULE 2: The Overhang Problem \u2014 Distance Multiplier \u2550\u2550\u2550 --><\/p>\n<section style=\"margin-bottom: 3.5rem; background: #f9fafb; border-radius: 12px; padding: clamp(1.5rem,3.5vw,2.5rem);\">\n<h2 style=\"font-size: clamp(20px,3vw,28px); font-weight: bold; color: #1a1a1a; border-bottom: 3px solid #0277bd; padding-bottom: .75rem; margin: 0 0 1.4rem;\">The Overhang Multiplier \u2014 How Mounting Distance Amplifies Bearing Load<\/h2>\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: #444; margin: 0 0 1.1rem;\">Korea Ever-Power catalogues specify the permissible radial load at a reference point \u2014 typically a distance <em>x_ref<\/em> from the output flange face. When the actual radial load is applied at a different distance (either closer or further from the flange), the effective bearing load changes. The relationship is derived from the bending moment at the output bearing.<\/p>\n<div style=\"background: #1a1a1a; border-radius: 8px; padding: 1.3rem 1.5rem; margin-bottom: 1.3rem;\">\n<p style=\"color: #90caf9; font-size: 11px; font-weight: bold; letter-spacing: 1px; margin: 0 0 .7rem;\">OVERHANG LOAD MULTIPLIER DERIVATION<\/p>\n<div style=\"font-family: monospace; font-size: clamp(11px,1.5vw,13px); color: #a5d6a7; line-height: 2.1;\">Bearing reaction at output bearing from overhang load F_r at distance x:<\/p>\n<p>F_bearing = F_r \u00d7 (x + a) \/ a<\/p>\n<p>Dove:<br \/>\nx = distance from gearbox flange face to load application point (mm)<br \/>\na = distance from gearbox flange face to output bearing centre (mm)<br \/>\n(internal dimension \u2014 from Korea Ever-Power datasheet)<\/p>\n<p>Catalogue permissible radial force F_r_perm is given at x = x_ref<br \/>\n\u2192 F_bearing_ref = F_r_perm \u00d7 (x_ref + a) \/ a<\/p>\n<p>At actual installation distance x_actual:<br \/>\nF_r_allowable = F_bearing_ref \u00d7 a \/ (x_actual + a)<\/p>\n<p>Simplified multiplier k = (x_ref + a) \/ (x_actual + a)<br \/>\nF_r_allowable = F_r_perm \u00d7 k<\/p>\n<p>Example: a = 40 mm, x_ref = 20 mm, x_actual = 60 mm<br \/>\nk = (20 + 40) \/ (60 + 40) = 60\/100 = <span style=\"color: #ef9a9a; font-weight: bold;\">0.60<\/span><br \/>\n\u2192 Permissible radial force reduced by <span style=\"color: #ef9a9a; font-weight: bold;\">40%<\/span> at 60mm overhang<\/div>\n<\/div>\n<div style=\"overflow-x: auto; margin-bottom: 1.2rem;\">\n<table style=\"width: 100%; border-collapse: collapse; font-size: clamp(11px,1.4vw,13px); min-width: 480px;\">\n<thead>\n<tr style=\"background: #0277bd; color: #fff;\">\n<th style=\"padding: .65rem .8rem; border: 1px solid #81d4fa; text-align: left; font-weight: bold;\">Actual overhang x_actual<\/th>\n<th style=\"padding: .65rem .8rem; border: 1px solid #81d4fa; text-align: center; font-weight: bold;\">Multiplier k (a=40mm, x_ref=20mm)<\/th>\n<th style=\"padding: .65rem .8rem; border: 1px solid #81d4fa; text-align: center; font-weight: bold;\">% of catalogue F_r_perm<\/th>\n<th style=\"padding: .65rem .8rem; border: 1px solid #81d4fa; text-align: center; font-weight: bold;\">Bearing L10 change<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background: #e8f5e9;\">\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; font-weight: 600;\">x = 0 mm (flush with flange)<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #1b5e20; font-weight: bold;\">k = 1.5<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #1b5e20; font-weight: bold;\">150% allowed<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #1b5e20;\">+3.4\u00d7 longer<\/td>\n<\/tr>\n<tr style=\"background: #fff;\">\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee;\">x = 20 mm (= x_ref)<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center;\">k = 1.0<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center;\">100% (catalogue)<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center;\">Baseline<\/td>\n<\/tr>\n<tr style=\"background: #f9f9f9;\">\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee;\">x = 40 mm<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #e65100;\">k = 0.75<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #e65100;\">75% allowed<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #e65100;\">\u221258% life<\/td>\n<\/tr>\n<tr style=\"background: #fff;\">\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee;\">x = 60 mm<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #c62828; font-weight: bold;\">k = 0.60<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #c62828; font-weight: bold;\">60% allowed<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #c62828;\">\u221278% life<\/td>\n<\/tr>\n<tr style=\"background: #f9f9f9;\">\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee;\">x = 100 mm<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #c62828; font-weight: bold;\">k = 0.44<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #c62828; font-weight: bold;\">44% allowed<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #c62828;\">\u221291% life<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<div style=\"background: #ffebee; border-left: 5px solid #c62828; border-radius: 0 8px 8px 0; padding: .9rem 1.2rem;\"><strong style=\"color: #c62828; font-size: 13px;\">The Korean rack-and-pinion installation trap: <\/strong><br \/>\n<span style=\"font-size: 13px; color: #444;\">In Korean gantry machine and automated guided vehicle rack-drive installations, the output shaft pinion is commonly mounted 60\u2013100 mm from the gearbox face to clear the mounting structure. As the table above shows, this seemingly modest overhang reduces the permissible radial force by 40\u201356% \u2014 more than halving the bearing-limited capacity compared to the catalogue value. Engineers who check only the torque rating against catalogue and ignore the overhang multiplier are selecting a gearbox that operates at 2\u20133\u00d7 its bearing-rated load, producing bearing failures within months rather than years.<\/span><\/div>\n<\/section>\n<p><!-- \u2550\u2550\u2550 MODULE 3: L10 Bearing Life Calculation \u2550\u2550\u2550 --><\/p>\n<section style=\"margin-bottom: 3.5rem;\">\n<h2 style=\"font-size: clamp(20px,3vw,28px); font-weight: bold; color: #1a1a1a; border-bottom: 3px solid #0277bd; padding-bottom: .75rem; margin: 0 0 1.4rem;\">L10 Bearing Life Calculation \u2014 From Applied Load to Expected Service Hours<\/h2>\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: #444; margin: 0 0 1.1rem;\">Once the actual bearing load is known (accounting for radial force, axial force, and any overhang multiplier), the expected L10 bearing life can be calculated using the ISO 281 standard formula. L10 is the life in millions of revolutions that 90% of a bearing population will reach before fatigue failure.<\/p>\n<div style=\"background: #1a1a1a; border-radius: 8px; padding: 1.3rem 1.5rem; margin-bottom: 1.3rem;\">\n<p style=\"color: #90caf9; font-size: 11px; font-weight: bold; letter-spacing: 1px; margin: 0 0 .7rem;\">ISO 281 BEARING LIFE CALCULATION<\/p>\n<div style=\"font-family: monospace; font-size: clamp(11px,1.5vw,13px); color: #a5d6a7; line-height: 2.1;\">L10 = (C \/ P)\u00b3 \u00d7 10\u2076 revolutions [for ball bearings, exponent = 3]<br \/>\nL10 = (C \/ P)^(10\/3) \u00d7 10\u2076 rev [for roller bearings, exponent = 10\/3]<\/p>\n<p>Dove:<br \/>\nC = basic dynamic load rating of the bearing (N) \u2014 from Korea Ever-Power datasheet<br \/>\nP = equivalent dynamic bearing load (N) \u2014 calculated from radial + axial forces<\/p>\n<p>P = X \u00d7 F_r + Y \u00d7 F_a<br \/>\nX = radial load factor, Y = axial load factor (from bearing catalogue, depends on F_a\/C\u2080 ratio)<br \/>\nFor pure radial load (F_a = 0): P = F_r<\/p>\n<p>Convert to hours: L10h = L10 \u00d7 10\u2076 \/ (n \u00d7 60)<br \/>\nn = output shaft speed (rpm)<\/p>\n<p>Example: C = 15,000 N, F_r = 5,000 N (pure radial), n = 50 rpm<br \/>\nP = 5,000 N<br \/>\nL10 = (15,000 \/ 5,000)\u00b3 \u00d7 10\u2076 = 27 \u00d7 10\u2076 revolutions<br \/>\nL10h = 27\u00d710\u2076 \/ (50 \u00d7 60) = <span style=\"color: #ffcc80; font-weight: bold;\">9,000 hours<\/span><\/p>\n<p>At F_r = 7,500 N (1.5\u00d7 overload):<br \/>\nL10 = (15,000 \/ 7,500)\u00b3 \u00d7 10\u2076 = 8 \u00d7 10\u2076 rev<br \/>\nL10h = 8\u00d710\u2076 \/ (50 \u00d7 60) = <span style=\"color: #ef9a9a; font-weight: bold;\">2,667 hours (\u221270%)<\/span><\/div>\n<\/div>\n<div style=\"overflow-x: auto; margin-bottom: 1.2rem;\">\n<table style=\"width: 100%; border-collapse: collapse; font-size: clamp(11px,1.4vw,13px); min-width: 480px;\">\n<thead>\n<tr style=\"background: #263238; color: #fff;\">\n<th style=\"padding: .65rem .8rem; border: 1px solid #37474f; text-align: left;\">Load ratio F_r \/ F_r_perm<\/th>\n<th style=\"padding: .65rem .8rem; border: 1px solid #37474f; text-align: center;\">P\/C ratio<\/th>\n<th style=\"padding: .65rem .8rem; border: 1px solid #37474f; text-align: center;\">L10 (millions of rev)<\/th>\n<th style=\"padding: .65rem .8rem; border: 1px solid #37474f; text-align: center;\">Hours at 50 rpm<\/th>\n<th style=\"padding: .65rem .8rem; border: 1px solid #37474f; text-align: center;\">vs catalogue life<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background: #e8f5e9;\">\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; font-weight: bold; color: #1b5e20;\">0.5\u00d7 (half load)<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center;\">0.167<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #1b5e20; font-weight: bold;\">216 M<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; font-weight: bold; color: #1b5e20;\">72,000 h<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #1b5e20;\">+700%<\/td>\n<\/tr>\n<tr style=\"background: #fff;\">\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; font-weight: bold;\">1.0\u00d7 (catalogue rated)<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center;\">0.333<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center;\">27 M<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; font-weight: bold;\">9,000 h<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center;\">Baseline<\/td>\n<\/tr>\n<tr style=\"background: #f9f9f9;\">\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; font-weight: bold; color: #e65100;\">1.25\u00d7 (modest overload)<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center;\">0.417<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #e65100;\">13.8 M<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #e65100;\">4,600 h<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #e65100;\">\u221249%<\/td>\n<\/tr>\n<tr style=\"background: #fff;\">\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; font-weight: bold; color: #c62828;\">1.5\u00d7 (significant overload)<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center;\">0.500<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #c62828; font-weight: bold;\">8 M<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #c62828; font-weight: bold;\">2,667 h<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #c62828;\">\u221270%<\/td>\n<\/tr>\n<tr style=\"background: #ffebee;\">\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; font-weight: bold; color: #c62828;\">2.0\u00d7 (severe overload)<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center;\">0.667<\/td>\n<td style=\"padding: .6rem .8mm; border: 1px solid #eee; text-align: center; color: #c62828; font-weight: bold;\">3.4 M<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #c62828; font-weight: bold;\">1,130 h<\/td>\n<td style=\"padding: .6rem .8rem; border: 1px solid #eee; text-align: center; color: #c62828;\">\u221287%<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p style=\"font-size: 12px; color: #888; font-style: italic;\">Based on C=15,000N example bearing, n=50rpm output. Your actual C value is on the Korea Ever-Power EP series datasheet. Apply the overhang multiplier from Module 2 to your radial force before entering this calculation.<\/p>\n<\/section>\n<p><!-- \u2550\u2550\u2550 MODULE 4: EP-AF vs EP-AB \u2014 Same Frame, Different Shaft Capacity \u2550\u2550\u2550 --><\/p>\n<section style=\"margin-bottom: 3.5rem;\">\n<h2 style=\"font-size: clamp(20px,3vw,28px); font-weight: bold; color: #1a1a1a; border-bottom: 3px solid #0277bd; padding-bottom: .75rem; margin: 0 0 1.4rem;\">EP-AF vs EP-AB \u2014 The Same Frame, Very Different Radial Load Capacity<\/h2>\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: #444; margin: 0 0 1.1rem;\">Korean engineers specifying planetary gearboxes for belt-drive or rack-drive applications frequently use the EP-AB series because it covers the required torque. What they sometimes overlook is that EP-AB and EP-AF share the same body diameter and mounting flange \u2014 but the <a style=\"color: #1b5e20; font-weight: 600; text-decoration: none;\" href=\"https:\/\/planetary-gearboxes.com\/it\/prodotto\/ep-af-high-rigidity-inline-planetary-gearbox\/\">Serie EP-AF ad alta rigidit\u00e0<\/a> uses a significantly larger-diameter output shaft and an upgraded output bearing system that doubles or triples the permissible radial load at the same frame size.<\/p>\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: #444; margin: 0 0 1.1rem;\">The shaft bending stiffness scales with diameter to the fourth power (I \u221d d\u2074). An EP-AF090 output shaft that is 1.4\u00d7 the diameter of the equivalent EP-AB090 shaft has 1.4\u2074 = 3.8\u00d7 the bending stiffness \u2014 which directly translates to a proportionally higher permissible radial load before the shaft deflection and bearing moment reach the rated limit.<\/p>\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: #444; margin: 0 0 1.2rem;\">The practical consequence: for any application where the output shaft carries a belt, chain, or gear that imposes a radial force, always check the radial load specification \u2014 not just the torque specification \u2014 and compare EP-AB vs EP-AF at the same frame size before finalising the order.<\/p>\n<div style=\"overflow-x: auto; margin-bottom: 1.3rem;\">\n<table style=\"width: 100%; border-collapse: collapse; font-size: clamp(11px,1.4vw,13px); min-width: 520px;\">\n<thead>\n<tr style=\"background: #1b5e20; color: #fff;\">\n<th style=\"padding: 0.65rem 0.8rem; border: 1px solid #c8e6c9; text-align: left; width: 16.9345%;\">Frame \/ Model<\/th>\n<th style=\"padding: 0.65rem 0.8rem; border: 1px solid #c8e6c9; text-align: center; width: 22.4969%;\">Output shaft \u00d8 (mm)<\/th>\n<th style=\"padding: 0.65rem 0.8rem; border: 1px solid #c8e6c9; text-align: center; width: 21.0136%;\">Rated torque (N\u00b7m)<\/th>\n<th style=\"padding: 0.65rem 0.8rem; border: 1px solid #c8e6c9; text-align: center; width: 22.2497%;\">F_r_perm at x_ref (N)<\/th>\n<th style=\"padding: 0.65rem 0.8rem; border: 1px solid #c8e6c9; text-align: center; width: 17.3053%;\">F_r ratio AF\/AB<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background: #fff;\">\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; font-weight: 600; width: 16.9345%;\"><a style=\"color: #0277bd; font-weight: bold; text-decoration: none;\" href=\"https:\/\/planetary-gearboxes.com\/it\/prodotto\/ep-ab-precision-inline-planetary-gearbox\/\">EP-AB 060<\/a><\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 22.4969%;\">22<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 21.0136%;\">37\u2013190<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; color: #0277bd; font-weight: bold; width: 22.2497%;\">730\u20131,200 N<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; font-style: italic; color: #888888; width: 17.3053%;\">\u2014<\/td>\n<\/tr>\n<tr style=\"background: #e8f5e9;\">\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; font-weight: 600; width: 16.9345%;\"><a style=\"color: #1b5e20; font-weight: bold; text-decoration: none;\" href=\"https:\/\/planetary-gearboxes.com\/it\/prodotto\/ep-af-high-rigidity-inline-planetary-gearbox\/\">EP-AF 060<\/a><\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 22.4969%;\">28<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 21.0136%;\">37\u2013190<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; color: #1b5e20; font-weight: bold; width: 22.2497%;\">1,500\u20132,400 N<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; font-weight: bold; color: #1b5e20; width: 17.3053%;\">~2\u00d7<\/td>\n<\/tr>\n<tr style=\"background: #fff;\">\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; font-weight: 600; width: 16.9345%;\">EP-AB 090<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 22.4969%;\">32<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 21.0136%;\">120\u2013550<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; color: #0277bd; font-weight: bold; width: 22.2497%;\">1,600\u20133,000 N<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; font-style: italic; color: #888888; width: 17.3053%;\">\u2014<\/td>\n<\/tr>\n<tr style=\"background: #e8f5e9;\">\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; font-weight: 600; width: 16.9345%;\">EP-AF 090<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 22.4969%;\">45<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 21.0136%;\">120\u2013550<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; color: #1b5e20; font-weight: bold; width: 22.2497%;\">4,000\u20137,500 N<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; font-weight: bold; color: #1b5e20; width: 17.3053%;\">~2.5\u00d7<\/td>\n<\/tr>\n<tr style=\"background: #fff;\">\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; font-weight: 600; width: 16.9345%;\">EP-AB 140<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 22.4969%;\">48<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 21.0136%;\">450\u20131,750<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; color: #0277bd; font-weight: bold; width: 22.2497%;\">4,000\u20136,000 N<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; font-style: italic; color: #888888; width: 17.3053%;\">\u2014<\/td>\n<\/tr>\n<tr style=\"background: #e8f5e9;\">\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; font-weight: 600; width: 16.9345%;\">EP-AF 140<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 22.4969%;\">65<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; width: 21.0136%;\">450\u20131,750<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; color: #1b5e20; font-weight: bold; width: 22.2497%;\">9,000\u201314,000 N<\/td>\n<td style=\"padding: 0.6rem 0.8rem; border: 1px solid #eeeeee; text-align: center; font-weight: bold; color: #1b5e20; width: 17.3053%;\">~2.3\u00d7<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p style=\"font-size: 12px; color: #888; font-style: italic;\">Values are indicative. Confirm exact F_r_perm and reference overhang distance x_ref from the Korea Ever-Power EP series datasheet for your specific model and ratio. F_r_perm varies with ratio as bearing pre-load changes across the ratio range.<\/p>\n<div style=\"background: #e8f5e9; border-left: 4px solid #1b5e20; border-radius: 0 8px 8px 0; padding: .9rem 1.2rem; margin-top: 1rem;\"><strong style=\"color: #1b5e20; font-size: 13px;\">When to specify EP-AF over EP-AB: <\/strong><br \/>\n<span style=\"font-size: 13px; color: #444;\">Any time the application involves a belt, chain, gear, or rack load on the output shaft \u2014 and the calculated radial force at the actual overhang distance exceeds 60% of the EP-AB permissible value \u2014 switch to EP-AF at the same frame size. The cost increment is typically 20\u201330% for the shaft upgrade, vs the cost of an early bearing failure and unplanned production stop. The upgrade requires no machine redesign: EP-AF uses the same mounting flange and body diameter as EP-AB at the same frame size.<\/span><\/div>\n<\/section>\n<p><!-- \u2550\u2550\u2550 MODULE 5: Right-Angle Gearbox \u2014 Bevel Stage Radial Load \u2550\u2550\u2550 --><\/p>\n<section style=\"margin-bottom: 3.5rem;\">\n<h2 style=\"font-size: clamp(20px,3vw,28px); font-weight: bold; color: #1a1a1a; border-bottom: 3px solid #0277bd; padding-bottom: .75rem; margin: 0 0 1.4rem;\">Right-Angle Gearboxes \u2014 How Bevel Gear Separation Force Adds to Shaft Load<\/h2>\n<div style=\"display: flex; flex-wrap: wrap; gap: 2rem; align-items: flex-start;\">\n<div style=\"flex: 1 1 340px;\">\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: #444; margin: 0 0 1rem;\">Right-angle planetary gearboxes integrate a bevel gear stage to redirect the output shaft by 90\u00b0. The bevel gear mesh generates gear separation forces \u2014 radial and axial components \u2014 that act internally on the bevel shaft bearings. These internal forces are already accounted for in the permissible radial load specification for the EP-ABR, EP-ADR, and <a style=\"color: #1b5e20; font-weight: 600; text-decoration: none;\" href=\"https:\/\/planetary-gearboxes.com\/it\/prodotto\/ep-afr-right-angle-high-rigidity-planetary-gearbox\/\">EP-AFR right-angle series<\/a>. However, when the right-angle output shaft also carries an external radial load (from a mounted sprocket or pinion), that external load adds to the already-loaded bevel shaft bearing system.<\/p>\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: #444; margin: 0 0 1rem;\">The practical rule for right-angle gearboxes with additional external loads:<\/p>\n<ul style=\"font-size: clamp(13px,1.6vw,14px); color: #444; margin: 0 0 1rem; padding-left: 1.5rem; line-height: 1.9;\">\n<li>Check the permissible radial load specification on the <em>right-angle output shaft specifically<\/em> \u2014 this value is lower than the inline series at the same frame size, because the bevel stage pre-loads the shaft bearings<\/li>\n<li>Apply the overhang multiplier from Module 2 to the external load at the actual mounting distance<\/li>\n<li>Confirm the combined bearing load (internal bevel separation + external radial) does not exceed the right-angle shaft permissible value<\/li>\n<li>If the external radial load is substantial, use the EP-AFR (high-rigidity right-angle) rather than EP-ABR at the same frame \u2014 the enlarged right-angle shaft diameter provides proportionally higher capacity<\/li>\n<\/ul>\n<div style=\"background: #e3f2fd; border-left: 4px solid #0277bd; border-radius: 0 8px 8px 0; padding: .85rem 1.1rem;\"><strong style=\"color: #0277bd; font-size: 13px;\">Korean CNC rotary axis case: <\/strong><br \/>\n<span style=\"font-size: 13px; color: #444;\">A Korean 5-axis machining centre used an EP-ABR090 P0 right-angle gearbox for the B-axis (tilting) with a 60mm overhang pinion driving the rotary table ring gear. The overhang multiplier at 60mm reduced the permissible radial force by 36% from the catalogue value. Combined with the table ring gear tangential force creating a bevel shaft axial component, the actual bearing load exceeded the EP-ABR permissible. Switching to EP-AFR090 (same frame, high-rigidity right-angle) with 1.7\u00d7 higher shaft load capacity resolved the bearing failure without any machine design change.<\/span><\/div>\n<\/div>\n<div style=\"flex: 0 0 auto; width: clamp(180px,30%,260px); max-width: 100%;\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-699\" src=\"https:\/\/planetary-gearboxes.com\/wp-content\/uploads\/2026\/06\/EP-ZDWE-Series-Right-Angle-Input-Precision-Planetary-Gearbox-1.webp\" alt=\"Riduttore epicicloidale di precisione ad ingresso ad angolo retto serie EP-ZDWE 1\" width=\"600\" height=\"600\" title=\"\" srcset=\"https:\/\/planetary-gearboxes.com\/wp-content\/uploads\/2026\/06\/EP-ZDWE-Series-Right-Angle-Input-Precision-Planetary-Gearbox-1.webp 600w, https:\/\/planetary-gearboxes.com\/wp-content\/uploads\/2026\/06\/EP-ZDWE-Series-Right-Angle-Input-Precision-Planetary-Gearbox-1-480x480.webp 480w\" sizes=\"(min-width: 0px) and (max-width: 480px) 480px, (min-width: 481px) 600px, 100vw\" \/><\/p>\n<div style=\"background: #f5f5f5; border-radius: 8px; padding: .9rem;\">\n<div style=\"font-size: 12px; font-weight: bold; color: #1a1a1a; margin-bottom: .5rem;\">Right-angle output shaft load summary<\/div>\n<div style=\"font-size: 11px; color: #444; line-height: 1.8;\"><strong>EP-ABR:<\/strong> Standard shaft \u00b7 Bevel pre-load already included \u00b7 External load reduces available capacity further<\/p>\n<p><strong>EP-AFR:<\/strong> High-rigidity shaft \u00b7 Same flange\/body as ABR \u00b7 ~1.7\u20132\u00d7 higher external radial load capacity \u00b7 First choice for any right-angle drive with significant external radial load<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n<p><!-- \u2550\u2550\u2550 MODULE 6: Worked Design Example \u2550\u2550\u2550 --><\/p>\n<section style=\"margin-bottom: 3.5rem; background: #f9fafb; border-radius: 12px; padding: clamp(1.5rem,3.5vw,2.5rem);\">\n<h2 style=\"font-size: clamp(20px,3vw,28px); font-weight: bold; color: #1a1a1a; border-bottom: 3px solid #0277bd; padding-bottom: .75rem; margin: 0 0 1.4rem;\">Worked Design Example \u2014 Korean Conveyor Belt Drive Shaft Selection<\/h2>\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: #444; margin: 0 0 1.1rem;\">A Korean food processing belt conveyor drive has the following specification: conveyor belt tension (tight side) 1,800 N, belt wrap 180\u00b0, pulley pitch diameter 200 mm (radius 100 mm), gearbox output speed 45 rpm, pulley mounted 50 mm from gearbox flange face, reference distance from Korea Ever-Power datasheet x_ref = 20 mm, a = 40 mm. Required service life \u2265 20,000 hours.<\/p>\n<div style=\"background: #1a1a1a; border-radius: 8px; padding: 1.3rem 1.5rem; margin-bottom: 1.3rem;\">\n<p style=\"color: #90caf9; font-size: 11px; font-weight: bold; letter-spacing: 1px; margin: 0 0 .7rem;\">STEP-BY-STEP SHAFT LOAD CALCULATION<\/p>\n<div style=\"font-family: monospace; font-size: clamp(11px,1.5vw,13px); color: #a5d6a7; line-height: 2.1;\">Step 1 \u2014 Belt radial force:<br \/>\nF_r = 2 \u00d7 T\u2081 \u00d7 sin(wrap\/2) = 2 \u00d7 1,800 \u00d7 sin(90\u00b0) = <span style=\"color: #ffcc80;\">3,600 N<\/span><br \/>\n(180\u00b0 wrap \u2192 tight side + slack side resultant = 2\u00d7T\u2081 for 180\u00b0)<\/p>\n<p>Step 2 \u2014 Drive torque:<br \/>\nT = T\u2081 \u00d7 r_pulley = 1,800 \u00d7 0.10 = <span style=\"color: #ffcc80;\">180 N\u00b7m<\/span><\/p>\n<p>Step 3 \u2014 Overhang multiplier (x=50mm, x_ref=20mm, a=40mm):<br \/>\nk = (20 + 40) \/ (50 + 40) = 60 \/ 90 = <span style=\"color: #ef9a9a;\">0.667<\/span><br \/>\nF_r_effective = 3,600 N (actual applied force)<br \/>\nRequired catalogue F_r_perm \u2265 3,600 \/ 0.667 = <span style=\"color: #ef9a9a; font-weight: bold;\">5,398 N<\/span><\/p>\n<p>Step 4 \u2014 Series selection:<br \/>\nT = 180 N\u00b7m \u2192 EP-AB090 (rated 120\u2013550 N\u00b7m) \u2713 for torque<br \/>\nEP-AB090 F_r_perm \u2248 3,000 N \u2192 3,000 \u00d7 0.667 = <span style=\"color: #c62828;\">2,001 N effective<\/span><br \/>\nActual load 3,600 N &gt; 2,001 N allowed: <span style=\"color: #c62828;\">EP-AB090 FAILS radial load \u2717<\/span><\/p>\n<p>EP-AF090 F_r_perm \u2248 7,500 N \u2192 7,500 \u00d7 0.667 = <span style=\"color: #a5d6a7;\">5,002 N effective<\/span><br \/>\nActual load 3,600 N &lt; 5,002 N allowed: <span style=\"color: #a5d6a7; font-weight: bold;\">EP-AF090 PASSES radial load \u2713<\/span><\/p>\n<p>Step 5 \u2014 L10h verification (EP-AF090, C \u2248 22,000 N):<br \/>\nP = F_bearing = 3,600 \u00d7 (50+40)\/40 = 3,600 \u00d7 2.25 = 8,100 N (at bearing)<br \/>\nL10 = (22,000\/8,100)\u00b3 \u00d7 10\u2076 = 7.14\u00b3 \u00d7 10\u2076 = <span style=\"color: #a5d6a7; font-weight: bold;\">364 M rev<\/span><br \/>\nL10h = 364\u00d710\u2076 \/ (45\u00d760) = <span style=\"color: #a5d6a7; font-weight: bold;\">134,800 hours \u226b 20,000 h target \u2713<\/span><\/div>\n<\/div>\n<div style=\"background: #e8f5e9; border-left: 4px solid #1b5e20; border-radius: 0 8px 8px 0; padding: .85rem 1.2rem;\"><strong style=\"color: #1b5e20; font-size: 13px;\">Key conclusion from this example: <\/strong><br \/>\n<span style=\"font-size: 13px; color: #444;\">The EP-AB090 was adequate for the torque requirement (180 N\u00b7m within 120\u2013550 N\u00b7m range) but completely inadequate for the radial load \u2014 the 50 mm overhang with 3,600 N belt tension exceeded the EP-AB090&#8217;s bearing capacity by 80%. Without the overhang calculation, a Korean engineer specifying only on torque would select EP-AB090, which would fail its output bearing within 2,000\u20134,000 hours. The EP-AF090 at the same frame size provides over 100,000 hours of bearing life for the same application \u2014 a fundamentally different outcome from a 20\u201330% cost increment.<\/span><\/div>\n<\/section>\n<p><!-- \u2550\u2550\u2550 MODULE 7: Axial Load Capacity and Limit \u2550\u2550\u2550 --><\/p>\n<section style=\"margin-bottom: 3.5rem;\">\n<h2 style=\"font-size: clamp(20px,3vw,28px); font-weight: bold; color: #1a1a1a; border-bottom: 3px solid #0277bd; padding-bottom: .75rem; margin: 0 0 1.4rem;\">Axial Load Capacity \u2014 Limits, Calculation and Common Exceedance Cases<\/h2>\n<div style=\"display: flex; flex-wrap: wrap; gap: 2rem; align-items: flex-start;\">\n<div style=\"flex: 1 1 300px;\">\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: #444; margin: 0 0 1rem;\">Axial load (thrust force along the shaft axis) is typically the less critical of the two shaft loads for most Korean applications \u2014 but several common drive configurations generate significant axial forces that must be explicitly checked against the gearbox specification.<\/p>\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: #444; margin: 0 0 1rem;\">Korea Ever-Power EP series permissible axial load F_a_perm is typically specified as a fraction of the radial load capacity \u2014 often 30\u201350% of F_r_perm for standard EP-AB and EP-AF. The output shaft bearing design is optimised for radial load; axial load is a secondary design parameter. When axial load approaches or exceeds F_a_perm, consider the <a style=\"color: #1b5e20; font-weight: 600; text-decoration: none;\" href=\"https:\/\/planetary-gearboxes.com\/it\/product\/ep-afh-ultra-precision-inline-planetary-gearbox\/\">Serie di ultra-precisione EP-AFH<\/a> whose cross-roller bearing output provides higher axial load capacity in the same frame size.<\/p>\n<div style=\"display: flex; flex-direction: column; gap: .7rem; margin-bottom: 1rem;\">\n<div style=\"background: #fff3e0; border-left: 3px solid #e65100; border-radius: 0 6px 6px 0; padding: .7rem .9rem;\"><strong style=\"font-size: 12px; color: #e65100;\">Helical gear mesh axial force<\/strong><\/p>\n<p style=\"font-size: 12px; color: #444; margin: .3rem 0 0; line-height: 1.6;\">F_a = F_tangential \u00d7 tan(\u03b2), where \u03b2 is the helix angle. At \u03b2 = 20\u00b0 and 500 N tangential force: F_a = 500 \u00d7 tan(20\u00b0) = 182 N. For high-torque helical drives this becomes significant \u2014 at 5,000 N tangential force: F_a = 1,820 N. Verify against F_a_perm.<\/p>\n<\/div>\n<div style=\"background: #fff3e0; border-left: 3px solid #e65100; border-radius: 0 6px 6px 0; padding: .7rem .9rem;\"><strong style=\"font-size: 12px; color: #e65100;\">Screw conveyor thrust<\/strong><\/p>\n<p style=\"font-size: 12px; color: #444; margin: .3rem 0 0; line-height: 1.6;\">Material resistance on screw flighting creates axial thrust proportional to the pitch force. At high throughput, this can reach 30\u201350% of the maximum rated output torque in axial force terms. Always calculate screw conveyor axial thrust separately and confirm against F_a_perm.<\/p>\n<\/div>\n<div style=\"background: #fff3e0; border-left: 3px solid #e65100; border-radius: 0 6px 6px 0; padding: .7rem .9rem;\"><strong style=\"font-size: 12px; color: #e65100;\">Misaligned flexible coupling<\/strong><\/p>\n<p style=\"font-size: 12px; color: #444; margin: .3rem 0 0; line-height: 1.6;\">Angular or parallel misalignment in flexible jaw couplings generates a small but continuous axial force that acts on the output bearing. For precision drives, ensure shaft-to-shaft alignment is within 0.05 mm TIR to minimise coupling-induced axial force.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div style=\"flex: 0 0 auto; width: clamp(180px,30%,260px); max-width: 100%;\"><img decoding=\"async\" style=\"width: 100%; height: auto; border-radius: 10px; box-shadow: 0 4px 18px rgba(0,0,0,.12); margin-bottom: 1rem;\" src=\"https:\/\/planetary-gearboxes.com\/wp-content\/uploads\/2026\/05\/Helical-Planetary-Gearbox-1.webp\" alt=\"helical planetary gearbox axial load capacity thrust bearing Korea Ever-Power EP-AFH cross roller\" title=\"\"><\/p>\n<div style=\"background: #1a1a1a; border-radius: 8px; padding: .9rem 1rem;\">\n<p style=\"color: #90caf9; font-size: 11px; font-weight: bold; margin: 0 0 .6rem;\">Axial load capacity guide<\/p>\n<div style=\"font-size: 11px; color: #a5d6a7; font-family: monospace; line-height: 1.9;\">EP-AB\/AF: F_a_perm<br \/>\n\u2248 30\u201350% of F_r_perm<\/p>\n<p>EP-AFH (cross roller):<br \/>\nEqual radial and axial<br \/>\ncapacity in both directions<br \/>\n\u2192 For high axial duty<\/p>\n<p>EP-AH New Line:<br \/>\nHigh axial + radial via<br \/>\nangular contact bearings<\/p><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n<p><!-- separator image before FAQ --><\/p>\n<div style=\"margin-bottom: 2rem;\"><img decoding=\"async\" style=\"width: 100%; height: auto; border-radius: 10px; box-shadow: 0 3px 14px rgba(0,0,0,.1);\" src=\"https:\/\/planetary-gearboxes.com\/wp-content\/uploads\/2026\/05\/BAF-Series-High-Precision-Planetary-Gearbox-1.webp\" alt=\"Korea Ever-Power EP-AF high rigidity shaft planetary gearbox radial axial load capacity selection\" title=\"\"><\/div>\n<p><!-- \u2550\u2550\u2550 MODULE 8: FAQ \u2550\u2550\u2550 --><\/p>\n<section style=\"margin-bottom: 3.5rem;\">\n<h2 style=\"font-size: clamp(20px,3vw,28px); font-weight: bold; color: #1a1a1a; border-bottom: 3px solid #0277bd; padding-bottom: .75rem; margin: 0 0 1.4rem;\">Frequently Asked Questions \u2014 Radial and Axial Load Capacity<\/h2>\n<div style=\"display: flex; flex-direction: column; gap: 0; border: 1px solid #e0e0e0; border-radius: 10px; overflow: hidden;\">\n<div style=\"padding: 1.1rem 1.4rem; border-bottom: 1px solid #eee; background: #fff;\">\n<h3 style=\"font-size: clamp(13px,1.8vw,15px); font-weight: bold; color: #1b5e20; margin: 0 0 .6rem; display: flex; align-items: flex-start; gap: .6rem;\"><span style=\"flex-shrink: 0; background: #1b5e20; color: #fff; border-radius: 4px; padding: 1px 7px; font-size: 12px; margin-top: 1px;\">Q<\/span><br \/>\nMy gearbox output bearing fails every 8\u201312 months on a Korean packaging machine film pull axis. What is the likely cause?<\/h3>\n<p style=\"margin: 0; font-size: clamp(12px,1.6vw,13px); color: #555; line-height: 1.75; padding-left: 1.8rem;\">Recurring output bearing failure at 8\u201312 months (approximately 5,000\u20137,500 operating hours in three-shift operation) with no increase in backlash suggests the failure is bearing fatigue from radial overload rather than gear wear. The most likely cause is the film reel dancer mechanism imposing a radial force on the gearbox output shaft at an overhang distance beyond the catalogue reference. Measure the actual reel tension at maximum load and the distance from the gearbox flange to the dancer pulley shaft. Apply the overhang calculation from Module 2 and compare the effective bearing load against the EP-AB permissible. If the load exceeds 70% of the permissible F_r at that overhang distance, switch to EP-AF at the same frame \u2014 the higher shaft rigidity will extend bearing life dramatically. This is the single most common cause of recurring output bearing failure on Korean packaging machine film pull drives.<\/p>\n<\/div>\n<div style=\"padding: 1.1rem 1.4rem; border-bottom: 1px solid #eee; background: #fafafa;\">\n<h3 style=\"font-size: clamp(13px,1.8vw,15px); font-weight: bold; color: #1b5e20; margin: 0 0 .6rem; display: flex; align-items: flex-start; gap: .6rem;\"><span style=\"flex-shrink: 0; background: #1b5e20; color: #fff; border-radius: 4px; padding: 1px 7px; font-size: 12px; margin-top: 1px;\">Q<\/span><br \/>\nCan I add an outboard bearing support to an EP-AB installation to improve radial load capacity without changing the gearbox?<\/h3>\n<p style=\"margin: 0; font-size: clamp(12px,1.6vw,13px); color: #555; line-height: 1.75; padding-left: 1.8rem;\">Yes \u2014 adding an outboard bearing support (a bearing block mounted to the machine structure, supporting the output shaft end beyond the mounted load) effectively converts the overhang installation to a simply-supported shaft configuration. This changes the bearing load calculation: instead of a cantilever bending moment acting entirely on the gearbox output bearing, the load is shared between the gearbox output bearing and the outboard bearing. The load share depends on the relative stiffness and distances. For a well-designed outboard support, the gearbox output bearing load can be reduced by 50\u201370%, dramatically extending bearing life without a gearbox change. Korea Ever-Power application engineering can provide the modified bearing load calculation for your specific outboard support geometry.<\/p>\n<\/div>\n<div style=\"padding: 1.1rem 1.4rem; border-bottom: 1px solid #eee; background: #fff;\">\n<h3 style=\"font-size: clamp(13px,1.8vw,15px); font-weight: bold; color: #1b5e20; margin: 0 0 .6rem; display: flex; align-items: flex-start; gap: .6rem;\"><span style=\"flex-shrink: 0; background: #1b5e20; color: #fff; border-radius: 4px; padding: 1px 7px; font-size: 12px; margin-top: 1px;\">Q<\/span><br \/>\nDoes the Korea Ever-Power permissible radial load vary with gear ratio within the same frame and series?<\/h3>\n<p style=\"margin: 0; font-size: clamp(12px,1.6vw,13px); color: #555; line-height: 1.75; padding-left: 1.8rem;\">Yes \u2014 the permissible radial load varies slightly with ratio, even within the same frame and series. This is because different ratios use different numbers of planet gears and different planet gear sizes, which changes the planet carrier bearing geometry and the output bearing pre-load state. For most practical selections the variation is less than 15% across the full ratio range, so using the minimum value in the datasheet is conservative and safe. For critical high-radial-load applications where you are close to the permissible limit, confirm the exact F_r_perm for your specific ratio from the Korea Ever-Power EP series datasheet or contact the application team.<\/p>\n<\/div>\n<div style=\"padding: 1.1rem 1.4rem; background: #fafafa;\">\n<h3 style=\"font-size: clamp(13px,1.8vw,15px); font-weight: bold; color: #1b5e20; margin: 0 0 .6rem; display: flex; align-items: flex-start; gap: .6rem;\"><span style=\"flex-shrink: 0; background: #1b5e20; color: #fff; border-radius: 4px; padding: 1px 7px; font-size: 12px; margin-top: 1px;\">Q<\/span><br \/>\nFor a Korean gantry machine where the rack-and-pinion drive uses a CV shaft between the gearbox and the pinion, does the radial load calculation still apply?<\/h3>\n<p style=\"margin: 0; font-size: clamp(12px,1.6vw,13px); color: #555; line-height: 1.75; padding-left: 1.8rem;\">When a <a style=\"color: #1b5e20; font-weight: 600; text-decoration: none;\" href=\"https:\/\/cvjointdriveshaft.com\/\" target=\"_blank\" rel=\"noopener\">precision CV drive shaft<\/a> connects the gearbox output to the pinion, the shaft transmits torque through angular offsets without transmitting the rack-pinion radial force back to the gearbox output shaft. The CV shaft&#8217;s constant-velocity joints absorb the misalignment without generating reactive forces at the gearbox output bearing. This means the gearbox output bearing sees only the torque reaction (very small radial component) and no rack-pinion contact force \u2014 a significant benefit for gearbox bearing life in high-overhang or offset drive configurations. The CV shaft itself must be rated for the transmitted torque and the angular offset, but the gearbox can be specified on torque alone when a CV shaft isolates it from the rack-pinion radial load.<\/p>\n<\/div>\n<\/div>\n<\/section>\n<p><!-- \u2550\u2550\u2550 CLOSING CTA \u2550\u2550\u2550 --><\/p>\n<section style=\"background: linear-gradient(135deg,#0277bd,#01579b); border-radius: 12px; padding: clamp(1.8rem,4vw,2.8rem); text-align: center; color: #fff; margin-bottom: 2rem;\">\n<h2 style=\"font-size: clamp(18px,2.8vw,26px); font-weight: 800; color: #fff; margin: 0 0 .8rem; border: none;\">Confirm Your Radial Load Specification with Korea Ever-Power<\/h2>\n<p style=\"font-size: clamp(13px,1.7vw,15px); color: rgba(255,255,255,.9); margin: 0 0 1.5rem; line-height: 1.7; max-width: 640px; margin-left: auto; margin-right: auto;\">Korea Ever-Power&#8217;s application team calculates the actual bearing load from your drive geometry \u2014 belt tension, overhang distance, chain configuration, or rack-pinion force \u2014 and confirms whether EP-AB or EP-AF is the correct series for your installation. Same working day in Korean.<\/p>\n<div style=\"display: flex; flex-wrap: wrap; justify-content: center; gap: 1rem;\"><a style=\"display: inline-block; background: #fff; color: #0277bd; font-weight: bold; font-size: clamp(13px,1.7vw,15px); padding: .8rem 1.8rem; border-radius: 6px; text-decoration: none;\" href=\"https:\/\/planetary-gearboxes.com\/it\/prodotto\/ep-af-high-rigidity-inline-planetary-gearbox\/\">EP-AF High-Rigidity Shaft \u2192<br \/>\n<\/a><br \/>\n<a style=\"display: inline-block; background: transparent; color: #fff; font-weight: bold; font-size: clamp(13px,1.7vw,15px); padding: .8rem 1.8rem; border-radius: 6px; text-decoration: none; border: 2px solid rgba(255,255,255,.7);\" href=\"https:\/\/planetary-gearboxes.com\/it\/prodotto\/ep-afr-right-angle-high-rigidity-planetary-gearbox\/\">EP-AFR Right-Angle High-Rigidity \u2192<br \/>\n<\/a><\/div>\n<\/section>\n<p>Redattore: Cxm<\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>Engineering Reference \u00b7 L10 Calculation \u00b7 Overhang Position \u00b7 AF vs AB Comparison Planetary Gearbox Radial Load Capacity \u2014 L10 Bearing Life and Shaft Selection Correctly specifying planetary gearbox radial load capacity prevents the most common cause of premature planetary gearbox output bearing failure in Korean industry is not under-rated torque \u2014 it is under-rated [&hellip;]<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[965],"tags":[],"class_list":["post-713","post","type-post","status-publish","format-standard","hentry","category-application-and-technical-guid"],"_links":{"self":[{"href":"https:\/\/planetary-gearboxes.com\/it\/wp-json\/wp\/v2\/posts\/713","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/planetary-gearboxes.com\/it\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/planetary-gearboxes.com\/it\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/it\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/it\/wp-json\/wp\/v2\/comments?post=713"}],"version-history":[{"count":1,"href":"https:\/\/planetary-gearboxes.com\/it\/wp-json\/wp\/v2\/posts\/713\/revisions"}],"predecessor-version":[{"id":714,"href":"https:\/\/planetary-gearboxes.com\/it\/wp-json\/wp\/v2\/posts\/713\/revisions\/714"}],"wp:attachment":[{"href":"https:\/\/planetary-gearboxes.com\/it\/wp-json\/wp\/v2\/media?parent=713"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/it\/wp-json\/wp\/v2\/categories?post=713"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/it\/wp-json\/wp\/v2\/tags?post=713"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}