{"id":1830,"date":"2026-07-20T05:12:57","date_gmt":"2026-07-20T05:12:57","guid":{"rendered":"https:\/\/gearrack.top\/?p=1830"},"modified":"2026-07-20T05:12:57","modified_gmt":"2026-07-20T05:12:57","slug":"spur-gears-for-conveyor-systems","status":"publish","type":"post","link":"https:\/\/gearrack.top\/ja\/spur-gears-for-conveyor-systems\/","title":{"rendered":"Spur Gears for Conveyor Systems"},"content":{"rendered":"
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GEAR APPLICATION GUIDE \u00b7 SPUR GEAR \u00b7 S02<\/span><\/p>\n

Spur Gears for Conveyor Systems:
\nDrive Design and Gear Selection Guide<\/span><\/h1>\n

Steel spur gears power belt, chain, bucket elevator and food processing conveyor drives worldwide. This guide covers module selection, speed ratio calculation, material hardening, plastic spur gear alternatives and mounting \u2014 from M2 light-duty to M16 mining head gear.<\/p>\n

C45 \u00b7 20CrMnTi \u00b7 316L \u00b7 Plastic<\/span>
\nModule M2 \u2013 M16 \u00b7 AGMA \/ DIN<\/span>
\n0.37 \u2013 400 kW Coverage<\/span><\/div>\n<\/div>\n<\/div>\n
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MODULE RANGE<\/p>\n

M2 \u2013 M16<\/p>\n

Light-duty belt conveyor to heavy mining bucket elevator spur gear head drive<\/p>\n<\/div>\n

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SPEED RATIO<\/p>\n

3:1 \u2013 25:1<\/p>\n

Single stage 3:1\u20138:1; two spur stages in series up to 25:1 for high-reduction conveyor drives<\/p>\n<\/div>\n

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TOOTH HARDNESS<\/p>\n

HRC 58\u201362<\/p>\n

Case carburized 20CrMnTi; induction hardened C45 reaches HRC 48\u201354 for medium conveyors<\/p>\n<\/div>\n

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DIN QUALITY<\/p>\n

DIN 5\u20139<\/p>\n

DIN 7\u20139 standard conveyor spur gears; DIN 5\u20136 ground pinion for pitch line velocity above 6 m\/s<\/p>\n<\/div>\n<\/div>\n

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Why Spur Gears Dominate Conveyor Drives<\/h2>\n

The spur gear is the default engineering choice for conveyor drive design \u2014 not by convention but by technical logic that holds across virtually every industrial conveyor category. Straight parallel teeth transmit torque between parallel shafts with zero axial thrust, which means the conveyor head pulley shaft bearings only carry radial load from belt tension rather than an additional axial force component that helical gears would impose. This simplifies both the bearing selection and the head pulley mounting arrangement, reducing assembly cost and potential sources of misalignment-induced bearing failure.<\/p>\n

\"Tractor<\/p>\n

Open-gear spur gears on large conveyor head drives \u2014 the pinion mounted on the motor gearbox output shaft meshing with a large spur wheel keyed directly to the conveyor head pulley shaft \u2014 expose the entire tooth contact zone to visual inspection at every maintenance walkthrough. Unlike enclosed helical gearboxes where deterioration requires either oil analysis or internal inspection, spur gear conveyor drives allow operators to detect pitting, spalling, and tooth tip cracking at a glance. This practical maintainability advantage is commercially significant in bulk materials handling operations where unplanned conveyor stoppages carry production costs that dwarf the cost of the gear itself.<\/p>\n

Korea Ever-Power’s spur gears for conveyor drives<\/a> span module M2 through M16 in C45, 20CrMnTi alloy steel, 316L stainless and engineering plastics \u2014 covering the full range from food processing line to open-pit mining conveyor head drive. All steel spur gears for conveyor applications are hobbed and shaved or ground to the specified DIN quality class, with tooth hardening by induction or case carburization matched to the conveyor’s duty cycle and shock loading requirements.<\/p>\n

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\u2699\ufe0f<\/p>\n

No Axial Thrust Load<\/h3>\n

Straight teeth engage parallel shafts with zero axial force component. Conveyor head shaft bearings carry only radial load from belt tension \u2014 bearing selection is straightforward, and there is no axial pre-load requirement that would complicate the head pulley mounting arrangement or increase bearing operating temperature.<\/p>\n<\/div>\n

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\ud83d\udd0d<\/p>\n

Field-Inspectable Tooth Wear<\/h3>\n

Open-gear spur gears on large conveyor head drives show tooth flank wear, pitting, and root cracking visually at every shift walkthrough. Operators can confirm acceptable wear margins without removing guards or opening gearbox housings \u2014 the most practical condition monitoring method available in dusty, wet, outdoor mining and aggregate plant environments.<\/p>\n<\/div>\n

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\ud83d\udcc8<\/p>\n

Lowest Cost per kW Transmitted<\/h3>\n

Spur gear hobbing is simpler than helical hobbing and far less expensive than bevel or worm manufacture. For the majority of conveyor drive environments where gear noise is not a primary design constraint \u2014 outdoor, mining, aggregate, bulk handling \u2014 a spur gear drive consistently delivers the lowest capital cost, lowest maintenance cost, and longest service life per kW of transmitted power among all gear drive types.<\/p>\n<\/div>\n<\/div>\n

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FOUR STANDARD SPUR GEAR CONVEYOR DRIVE CONFIGURATIONS<\/p>\n

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01 \u2014 Open Gear Head Drive<\/p>\n

Large spur wheel (OD 400\u20131,200 mm) keyed directly to conveyor head pulley shaft; driven by motor-mounted pinion through an exposed gear mesh. Standard for bucket elevators, cement plant conveyors, grain handling systems and aggregate plant conveyor head drives where enclosed gearbox dimensions and cost are not justified.<\/p>\n<\/div>\n

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02 \u2014 Enclosed Spur Gearbox<\/p>\n

Cast iron or fabricated steel housing, splash-lubricated ISO VG 220\u2013320 gear oil, flanged to motor and conveyor head shaft coupling. Standard for 2.2\u201375 kW industrial belt and chain conveyors where dust, weather, or safety regulations exclude open-gear arrangements. Service life 40,000\u201380,000 hours with correct oil selection and change intervals.<\/p>\n<\/div>\n

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03 \u2014 Two-Stage In-Line Reducer<\/p>\n

Two spur gear pairs in series within a single cast housing achieve total ratios up to 25:1 \u2014 used where motor speed is high and conveyor belt speed is very low, such as precision assembly conveyors, slow slat conveyors for automotive body panels, and temperature-controlled storage conveyors requiring precise indexing speed.<\/p>\n<\/div>\n

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04 \u2014 Anti-Runback Backstop<\/p>\n

Ratchet or sprag clutch backstop integrated with the spur gear drive on inclined belt conveyors above 10\u00b0 \u2014 prevents the loaded belt from running back under gravity on motor trip or soft-start failure. Standard design requirement for all inclined mining and aggregate conveyors above 5\u00b0 inclination and all inclined bucket elevator drives.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

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Module Selection for Conveyor Spur Gear Drives<\/h2>\n

Module \u2014 the ratio of the pitch circle diameter to the tooth count \u2014 is the single most important parameter in conveyor spur gear drive design. Module determines tooth size and therefore the load-carrying capacity per unit face width, the centre distance achievable for a given gear ratio, and the pitch line velocity at a given rotational speed. Under-selecting module for a heavy conveyor drive is the most common cause of premature spur gear tooth root fatigue failure; over-selecting increases cost, weight, and centre distance without benefit.<\/p>\n

The table below gives Korea Ever-Power’s first-pass module recommendations by conveyor type and power class. These are starting points for preliminary drive layout \u2014 full confirmation via Lewis bending stress calculation and AGMA or ISO 6336 pitting resistance calculation at the final design stage is always required for conveyor drives above 7.5 kW or above service factor 1.5.<\/p>\n

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CONVEYOR TYPE<\/th>\nPOWER<\/th>\nMODULE<\/th>\nFACE WIDTH<\/th>\nMATERIAL<\/th>\nSERVICE FACTOR<\/th>\n<\/tr>\n<\/thead>\n
Light belt \/ roller conveyor<\/td>\n0.37\u20132.2 kW<\/td>\nM2 \u2013 M4<\/td>\n20\u201340 mm<\/td>\nC45 \/ Nylon<\/td>\n1.25<\/td>\n<\/tr>\n
Medium belt \/ chain conveyor<\/td>\n2.2\u201315 kW<\/td>\nM4 \u2013 M8<\/td>\n40\u201380 mm<\/td>\nC45 \/ 40Cr<\/td>\n1.50<\/td>\n<\/tr>\n
Heavy industrial conveyor<\/td>\n15\u201375 kW<\/td>\nM6 \u2013 M10<\/td>\n80\u2013140 mm<\/td>\n20CrMnTi<\/td>\n1.75<\/td>\n<\/tr>\n
Bucket elevator \/ mining<\/td>\n75\u2013400 kW+<\/td>\nM10 \u2013 M16<\/td>\n140\u2013250 mm<\/td>\n20CrMnTi \/ 18CrNiMo<\/td>\n2.00\u20132.50<\/td>\n<\/tr>\n
Food processing conveyor<\/td>\n0.37\u20137.5 kW<\/td>\nM2 \u2013 M5<\/td>\n25\u201350 mm<\/td>\n316L \/ POM<\/td>\n1.25<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

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SPEED RATIO WORKED EXAMPLE \u2014 7.5 kW BELT CONVEYOR AT 1.2 m\/s<\/p>\n

1<\/span><\/p>\n

Head pulley RPM:<\/strong> Belt speed 1.2 m\/s, head pulley \u2205315 mm \u2192 RPM = (1.2 \u00d7 60) \u00f7 (\u03c0 \u00d7 0.315) = 72.8 RPM<\/strong><\/p>\n<\/div>\n

2<\/span><\/p>\n

Total ratio needed:<\/strong> 4-pole motor 1,450 RPM \u00f7 72.8 RPM = 19.9:1<\/strong> \u2192 split into two spur gear stages for compactness<\/p>\n<\/div>\n

3<\/span><\/p>\n

Stage split:<\/strong> Stage 1 = 4.5:1 (20T pinion \/ 90T wheel); Stage 2 = 4.4:1 (18T \/ 79T) \u2192 total 19.8:1 \u2713<\/strong> \u2014 within 1% of target<\/p>\n<\/div>\n

4<\/span><\/p>\n

Module from power:<\/strong> Design power = 7.5 kW \u00d7 service factor 1.5 = 11.25 kW. Pinion torque at 1,450 RPM = 74 Nm \u2192 select M5 C45 induction hardened, 20T pinion, 50 mm face width<\/strong> \u2192 root bending stress 138 MPa, within C45 induction hardened allowable 245 MPa \u2713<\/p>\n<\/div>\n<\/div>\n<\/section>\n

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Spur Gear Material and Hardening Selection<\/h2>\n
\"forged
Korea Ever-Power forged spur gears for heavy-duty conveyor head drives \u2014 20CrMnTi alloy steel forging blank, case carburized to 1.0\u20131.5 mm depth, quenched and tempered to HRC 58\u201362 tooth surface, finish-ground to DIN 6 quality class. Core hardness HB 310\u2013360 provides impact toughness for bucket elevator shock loading while the hard tooth case resists pitting and abrasive wear at mining conveyor pitch line velocities of 1\u20134 m\/s. Bending fatigue endurance \u03c3F<\/sub> \u2265 400 MPa vs 170 MPa for normalised C45 \u2014 allowing smaller module or narrower face width at the same transmitted power. Korea Ever-Power supplies matched spur pinion-and-wheel sets for bucket elevator head drive replacement with individual gear measurement report confirming DIN quality class.<\/figcaption><\/figure>\n
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C45 Carbon Steel<\/p>\n

The standard spur gear material for light and medium belt conveyor drives up to 15 kW. Normalised C45: HB 170\u2013210, allowable bending stress \u03c3F<\/sub> = 145\u2013175 MPa, allowable contact stress \u03c3H<\/sub> = 520\u2013580 MPa. Induction hardening the tooth flank and root raises surface hardness to HRC 48\u201354 and increases \u03c3H<\/sub> to 900\u20131,050 MPa, extending conveyor spur gear service life 2\u20133\u00d7 vs normalised without the cost and distortion risk of full case carburization. Korea Ever-Power stocks C45 normalised and induction-hardened spur gear blanks in standard modules for fast-turnaround conveyor repair orders.<\/p>\n

\u2713 Best value for indoor M4\u2013M8 belt conveyor<\/p>\n<\/div>\n

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20CrMnTi Alloy Steel<\/p>\n

China’s most widely used case-carburizing alloy steel for heavy-duty conveyor spur gears. Case carburization to 0.8\u20131.5 mm depth followed by quench and low-temperature temper produces: HRC 58\u201362 tooth surface, \u03c3F<\/sub> = 380\u2013430 MPa, \u03c3H<\/sub> = 1,400\u20131,550 MPa. The hard case resists abrasion at mining conveyor pitch line velocities; the ductile core (HB 310\u2013360) absorbs the shock torques of rock-jam events and emergency stops that would fracture a through-hardened gear. Ground to DIN 5\u20136 for high-speed conveyor pinions above 6 m\/s pitch line velocity.<\/p>\n

\u2713 Standard for M8\u2013M16 heavy and mining conveyor<\/p>\n<\/div>\n

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316L Stainless Steel<\/p>\n

The material of choice for food processing, dairy, beverage and pharmaceutical conveyor spur gears where daily CIP washdown with NaOH or hypochlorite solution would corrode carbon steel within weeks. 316L with 2\u20133% molybdenum provides enhanced chloride pitting resistance. HB 160\u2013200, \u03c3F<\/sub> = 130\u2013150 MPa \u2014 lower than carbon steel; use the next module up from the C45 calculation. NSF H1 food-grade lubricant is compatible. CIP-proof to 85\u00b0C NaOH 2% daily. FDA and REACH documentation provided by Korea Ever-Power for food conveyor spur gear orders.<\/p>\n

\u2713 Required for daily CIP washdown conveyor<\/p>\n<\/div>\n

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POM \/ MC Nylon \/ UHMWPE<\/p>\n

Plastic spur gears<\/a> for sealed light-duty conveyor drives to 1.5 kW. POM: self-lubricating (\u03bc \u2248 0.10), moisture-stable, FDA-listed, ideal for food and clean-room conveyors. MC Nylon oil-containing grade (green colour): \u03bc \u2248 0.06, higher impact strength than POM, preferred for sealed pharmaceutical and sorting conveyor drives. UHMWPE: lowest friction, immune to virtually all chemical attack, for chemical plant conveyor drives where carbon steel would corrode in weeks.<\/p>\n

\u2713 Food, pharma, chemical conveyor <1.5 kW<\/p>\n<\/div>\n<\/div>\n<\/section>\n

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Spur Gear Specifications by Conveyor Type<\/h2>\n

Each major conveyor type creates distinct demands on the spur gear drive in terms of shock loading, environmental exposure, speed, and duty cycle. The following breakdown covers the four most common conveyor categories handled by Korea Ever-Power.<\/p>\n

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TYPE 01<\/p>\n

FLAT BELT
\nCONVEYOR<\/p>\n<\/div>\n

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Specification:<\/strong> M4\u2013M8, C45 induction hardened, 20\u201324T pinion, ratio 4:1\u20136:1, pitch line velocity 2\u20135 m\/s, enclosed splash-lubricated gearbox. Service factor 1.25\u20131.5. Motor power typically 1.5\u201322 kW. The most common conveyor spur gear application worldwide \u2014 logistics and distribution centres, automotive assembly line transfer, food production belt conveyors, general manufacturing. Anti-runback:<\/strong> inclined belt conveyors above 10\u00b0 require ratchet or sprag backstop integrated with the spur gear drive output shaft.<\/p>\n<\/div>\n<\/div>\n

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TYPE 02<\/p>\n

ROLLER CHAIN
\nCONVEYOR<\/p>\n<\/div>\n

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Specification:<\/strong> M5\u2013M10, 20CrMnTi case carburized HRC 58\u201362, ratio 3:1\u20135:1 to the drive sprocket shaft, open-gear or enclosed gearbox. Critical design note:<\/strong> roller chain chordal action generates periodic impulse loads at each chain pitch engagement \u2014 always apply service factor 1.5\u20132.0 minimum. Motor power typically 3.7\u201337 kW. Applications: automotive body shop paint booth chain conveyors, foundry casting line slat conveyors, overhead power-and-free chain conveyors in appliance assembly.<\/p>\n<\/div>\n<\/div>\n

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TYPE 03<\/p>\n

BUCKET
\nELEVATOR<\/p>\n<\/div>\n

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Specification:<\/strong> M10\u2013M16, 20CrMnTi or 18CrNiMo7 ground to DIN 6, large spur wheel OD 600\u20131,200 mm on head shaft, service factor 1.75\u20132.25. Motor power typically 30\u2013400 kW. The highest-load spur gear conveyor application \u2014 cement plant clinker elevators, grain handling, coal handling, aggregate bucket elevators. Belt takeup transient loads during start-up and belt jam events impose peak torques 3\u20135\u00d7 rated; 20CrMnTi case carburized with ductile core is essential. Korea Ever-Power supplies matched sets with individual gear measurement report.<\/p>\n<\/div>\n<\/div>\n

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TYPE 04<\/p>\n

FOOD
\nCONVEYOR<\/p>\n<\/div>\n

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Specification:<\/strong> M2\u2013M5, 316L stainless or POM plastic, NSF H1 food-grade lubricant, enclosed IP67 for twice-daily CIP washdown. POM spur gears (self-lubricating, zero metal contamination risk, FDA-listed) for bakery and confectionery conveyors below 1.0 kW; 316L for meat, dairy, and beverage conveyors to 7.5 kW where higher torque capacity is required. Korea Ever-Power provides FDA 21 CFR, EU 10\/2011, and REACH SVHC documentation for food conveyor spur gear orders.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

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Mounting, Lubrication and Maintenance Intervals<\/h2>\n
\"conveyor
Korea Ever-Power gear measurement and quality inspection for conveyor drive spur gears \u2014 tooth spacing error, profile form error, lead error, pitch diameter, runout, and surface roughness Ra measured by Klingelnberg gear analyser and CMM and reported to the specified DIN quality class for each production batch. All conveyor spur gear orders shipped with individual measurement certificate; case-hardened gears additionally include heat treatment report (case depth cross-section, surface HRC at five tooth positions, core HB).<\/figcaption><\/figure>\n
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MOUNTING REQUIREMENTS<\/h3>\n