{"id":2052,"date":"2026-07-22T08:07:22","date_gmt":"2026-07-22T08:07:22","guid":{"rendered":"https:\/\/gearrack.top\/?p=2052"},"modified":"2026-07-22T08:07:22","modified_gmt":"2026-07-22T08:07:22","slug":"mc-nylon-gears-for-heavy-load-industrial-applications","status":"publish","type":"post","link":"https:\/\/gearrack.top\/ja\/mc-nylon-gears-for-heavy-load-industrial-applications\/","title":{"rendered":"MC Nylon Gears for Heavy-Load Industrial Applications"},"content":{"rendered":"<div style=\"font-family: 'Helvetica Neue',Arial,sans-serif; color: #1c2330; line-height: 1.8; background: #f4f6f9; margin: 0; padding: 0;\">\n<div style=\"background: #1c2330; background-image: linear-gradient(148deg,rgba(28,35,48,0.97) 0%,rgba(28,35,48,0.86) 55%,rgba(37,99,168,0.40) 100%),url('https:\/\/gearrack.top\/wp-content\/uploads\/2026\/07\/Plastic-Gears.webp'); background-size: cover; background-position: center 40%; padding: clamp(52px,8vw,96px) clamp(20px,5vw,64px) clamp(56px,7vw,80px); position: relative;\">\n<div style=\"position: absolute; top: 0; left: 0; right: 0; height: 5px; background: linear-gradient(90deg,#1c2330,#2563a8,#f97316,#2563a8,#1c2330);\"><\/div>\n<div style=\"position: absolute; bottom: -1px; left: 0; right: 0; height: 48px; background: #f4f6f9; clip-path: polygon(0 100%,100% 100%,100% 0);\"><\/div>\n<div style=\"max-width: 800px; position: relative; z-index: 2;\"><span style=\"display: inline-block; background: #2563a8; color: #fff; font-size: 9px; font-weight: 800; letter-spacing: 3px; text-transform: uppercase; padding: 4px 12px; border-radius: 2px; margin-bottom: 18px;\">GEAR APPLICATION GUIDE \u00b7 PLASTIC GEAR \u00b7 PL05<\/span><\/p>\n<h1 style=\"font-size: clamp(26px,4.5vw,46px); font-weight: 900; color: #fff; line-height: 1.1; margin: 0 0 18px; letter-spacing: -0.5px;\">MC Nylon Gears for Heavy-Load Industrial Applications:<br \/>\n<span style=\"color: #f97316;\">Cast Polyamide Gear Drives, Large-Module Plastic Gears and Anti-Static MC Nylon<\/span><\/h1>\n<p style=\"font-size: clamp(14px,1.8vw,16px); color: #8fa3bf; line-height: 1.72; margin: 0 0 26px; max-width: 660px;\">MC nylon \u2014 monomer cast polyamide 6, manufactured by casting liquid caprolactam directly into a mould rather than injection moulding pre-polymerised pellets \u2014 produces a plastic gear blank with a degree of crystallinity 5\u201315% higher than injection moulded PA6, significantly lower residual stress, and a much larger achievable part size than injection moulding permits. These properties make MC nylon the material of choice for large-diameter, heavy-load plastic gears (OD above 200 mm, face width above 50 mm) in industrial drives where the economics of a metal gear are unfavourable (corrosion maintenance cost, noise in populated industrial facilities, chemical media compatibility) but where injection moulded plastic gears are too small or not stiff enough for the application. Korea Ever-Power machines MC nylon gears from cast billets for applications spanning crane bridge drives, concrete mixer auxiliary gears, paper mill drive auxiliary components, and chemical plant metering drives.<\/p>\n<div style=\"display: flex; flex-wrap: wrap; gap: 8px;\"><span style=\"border: 1px solid rgba(37,99,168,0.7); color: #7fa8d4; font-size: 10px; font-weight: bold; padding: 5px 13px; border-radius: 2px; letter-spacing: 1px; text-transform: uppercase;\">MC Nylon PA6 \u00b7 Oil-Filled \u00b7 Anti-Static \u00b7 M5\u2013M20<\/span><br \/>\n<span style=\"border: 1px solid rgba(249,115,22,0.6); color: #f97316; font-size: 10px; font-weight: bold; padding: 5px 13px; border-radius: 2px; letter-spacing: 1px; text-transform: uppercase;\">OD 100\u2013800mm \u00b7 High Crystallinity \u00b7 Heavy-Load<\/span><br \/>\n<span style=\"border: 1px solid rgba(255,255,255,0.15); color: #8fa3bf; font-size: 10px; font-weight: bold; padding: 5px 13px; border-radius: 2px; letter-spacing: 1px; text-transform: uppercase;\">Crane \u00b7 Paper Mill \u00b7 Chemical Plant \u00b7 Mixer \u00b7 Mining<\/span><\/div>\n<\/div>\n<\/div>\n<div style=\"max-width: 1100px; margin: 0 auto; padding: 0 clamp(16px,3vw,40px);\">\n<div style=\"display: flex; flex-wrap: wrap; gap: 2px; background: #c8d4e3; border-radius: 6px; overflow: hidden; box-shadow: 0 4px 18px rgba(28,35,48,0.11); margin-top: 48px;\">\n<div style=\"flex: 1 1 150px; background: #fff; padding: 20px 22px;\">\n<p style=\"font-size: 9px; font-weight: 800; letter-spacing: 2.5px; text-transform: uppercase; color: #2563a8; margin: 0 0 6px;\">MODULE RANGE<\/p>\n<p style=\"font-size: 26px; font-weight: 900; color: #1c2330; margin: 0 0 5px; line-height: 1;\">M5 \u2013 M20<\/p>\n<p style=\"font-size: 12.5px; color: #64748b; margin: 0; line-height: 1.5;\">MC nylon industrial gear module range. Crane bridge auxiliary drive: M6\u2013M10. Concrete mixer ring drive auxiliary: M8\u2013M14. Paper mill spreader roll drive: M5\u2013M8. Chemical plant corrosion-resistant drive: M6\u2013M12. Large plastic worm gear (plastic worm wheel): M5\u2013M10. The large module reflects the fact that MC nylon gears are used in large-OD, low-speed applications where the tooth must be physically large enough to be machined from the cast billet without excessive waste<\/p>\n<\/div>\n<div style=\"flex: 1 1 150px; background: #fff; padding: 20px 22px;\">\n<p style=\"font-size: 9px; font-weight: 800; letter-spacing: 2.5px; text-transform: uppercase; color: #2563a8; margin: 0 0 6px;\">OD RANGE<\/p>\n<p style=\"font-size: 26px; font-weight: 900; color: #1c2330; margin: 0 0 5px; line-height: 1;\">100 \u2013 800 mm<\/p>\n<p style=\"font-size: 12.5px; color: #64748b; margin: 0; line-height: 1.5;\">MC nylon gear outer diameter range. Korea Ever-Power casts and machines MC nylon gears up to 800 mm OD from a single cast billet. The upper limit is set by the available billet casting diameter (Korea Ever-Power casts billets to 850 mm OD \u00d7 400 mm height). Above 800 mm OD, MC nylon can be cast as a ring (annular casting) or machined from a multi-segment assembly, reducing material waste for large-OD thin-rim designs<\/p>\n<\/div>\n<div style=\"flex: 1 1 150px; background: #fff; padding: 20px 22px;\">\n<p style=\"font-size: 9px; font-weight: 800; letter-spacing: 2.5px; text-transform: uppercase; color: #2563a8; margin: 0 0 6px;\">KEY VARIANTS<\/p>\n<p style=\"font-size: 26px; font-weight: 900; color: #1c2330; margin: 0 0 5px; line-height: 1;\">Natural \/ Oil \/ AS<\/p>\n<p style=\"font-size: 12.5px; color: #64748b; margin: 0; line-height: 1.5;\">MC nylon gear variants. Natural (MC Nylon 6): standard grade, blue-grey colour, general industrial use. Oil-filled (MC Nylon + 8% mineral oil): reduced friction coefficient (0.20 vs 0.32 unfilled), extended dry-run life \u2014 for drives without accessible lubrication. Anti-static (MC Nylon AS): surface resistivity \u2264 10\u2076 \u03a9, for mining, petrochemical, and flour mill applications where static discharge from the gear could ignite dust or vapour<\/p>\n<\/div>\n<div style=\"flex: 1 1 150px; background: #fff; padding: 20px 22px;\">\n<p style=\"font-size: 9px; font-weight: 800; letter-spacing: 2.5px; text-transform: uppercase; color: #2563a8; margin: 0 0 6px;\">ADVANTAGES<\/p>\n<p style=\"font-size: 26px; font-weight: 900; color: #1c2330; margin: 0 0 5px; line-height: 1;\">Lower Noise &amp; Corrosion<\/p>\n<p style=\"font-size: 12.5px; color: #64748b; margin: 0; line-height: 1.5;\">MC nylon gear advantages over steel in industrial heavy drives: (1) 10\u201315 dB(A) quieter gear mesh \u2014 significant in paper mills and crane halls where noise is a recognised health and safety issue. (2) No corrosion in humid, chemical, or outdoor environments \u2014 no painting or galvanising required. (3) Self-lubricating in the oil-filled variant \u2014 eliminates the lubrication maintenance schedule. (4) Lower inertia \u2014 density 1.15 g\/cm\u00b3 vs 7.85 g\/cm\u00b3 for steel, reducing the dynamic load on the motor shaft at startup<\/p>\n<\/div>\n<\/div>\n<section style=\"margin: 64px 0 0;\">\n<h2 style=\"font-size: clamp(18px,2.6vw,24px); font-weight: 800; color: #1c2330; margin: 0 0 20px; padding-bottom: 10px; border-bottom: 3px solid #2563a8;\">MC Nylon vs Injection Moulded Nylon \u2014 Why Cast Polyamide Outperforms at Large Size<\/h2>\n<p style=\"font-size: 15.5px; margin: 0 0 20px;\">The distinction between MC nylon (monomer cast polyamide 6) and injection moulded PA6 is not merely one of manufacturing method \u2014 it produces fundamentally different material properties that are significant for heavy-load gear applications. The casting process (where liquid caprolactam monomer polymerises in situ in the mould at atmospheric pressure and 150\u2013170\u00b0C) produces a much more uniform crystalline structure than injection moulding (where the same polymer is injected under high pressure into a cold mould, producing a skin-core structure with a highly oriented amorphous skin and a less crystalline core). The MC nylon&#8217;s higher and more uniform crystallinity translates to a 15\u201325% higher tensile strength (85 MPa vs 70 MPa for injection moulded PA6), a 20\u201330% higher flexural modulus (3.2 GPa vs 2.6 GPa), and significantly lower residual stress throughout the billet. This lower residual stress is critical for large gears \u2014 an injection moulded PA6 gear above 150 mm OD can warp measurably during the weeks after demoulding as the frozen-in injection moulding stresses gradually relax, invalidating the tooth profile accuracy achieved by the injection mould. An MC nylon gear machined from a properly annealed cast billet has negligible residual stress \u2014 the machined dimensions are stable from machining to installation and throughout the service life.<\/p>\n<p style=\"font-size: 15.5px; margin: 0 0 20px;\">Korea Ever-Power&#8217;s <a style=\"color: #2563a8; font-weight: bold; text-decoration: none; border-bottom: 2px solid #f97316;\" href=\"https:\/\/gearrack.top\/ja\/product-category\/plastic-gear\/\">MC nylon gears for heavy-load industrial applications<\/a> are manufactured from in-house cast billets \u2014 Korea Ever-Power operates its own MC nylon casting facility, casting billets in standard OD sizes (150, 200, 300, 400, 500, 600, 700, 800 mm OD) and heights up to 400 mm, in natural, oil-filled, and anti-static grades. The casting process includes a post-casting annealing cycle (holding the cast billet at 100\u00b0C for 2\u20134 hours, depending on billet diameter, to complete the polymerisation and relieve any thermal gradients from the exothermic polymerisation reaction) that is the critical quality step \u2014 inadequately annealed billets contain residual polymerisation shrinkage stress that can cause the billet to crack during or after machining. Korea Ever-Power&#8217;s quality protocol requires a hardness check (Rockwell HRR hardness at 5 positions on the billet cross-section, confirming uniform hardness without variation that would indicate incomplete polymerisation zones) and a weight check (confirming the billet density is within \u00b10.02 g\/cm\u00b3 of the target value, indicating complete polymerisation) before any billet is released to the machining department.<\/p>\n<p style=\"font-size: 15.5px; margin: 0 0 24px;\">The oil-filled MC nylon variant is the most important specialty grade for heavy-load industrial gear applications where re-lubrication is impractical. The internal oil content (8% by weight of mineral oil, incorporated into the polymer during the casting polymerisation) is released at the gear tooth surface as a thin boundary film under the contact pressure of the gear mesh \u2014 this in-situ oil film reduces the boundary friction coefficient from 0.32 (dry unfilled MC nylon against steel) to 0.20 (oil-filled MC nylon against steel), reducing the gear mesh heat generation and extending the tooth wear life. The oil-filled grade is particularly valuable in applications where the gear tooth surface temperature under load approaches the PA6 glass transition zone (above 80\u00b0C) \u2014 the lower friction coefficient of the oil-filled grade reduces the frictional heat generation per mesh cycle, keeping the tooth surface temperature below the critical threshold where surface softening and accelerated wear would begin. Korea Ever-Power specifies oil-filled MC nylon as the standard grade for all crane bridge drive gears and paper mill drive auxiliary gears \u2014 the two applications where the combination of intermittent heavy load (crane) or continuous moderate load (paper mill) with limited lubrication access makes the self-lubricating grade the most practical and economical long-term choice.<\/p>\n<figure style=\"margin: 0 0 28px;\"><img decoding=\"async\" style=\"width: 100%; height: auto; display: block; border-radius: 6px; border: 1px solid #d1d9e6;\" title=\"MC Nylon Heavy Load Industrial Gear \u2014 Korea Ever-Power\" src=\"https:\/\/gearrack.top\/wp-content\/uploads\/2026\/07\/Plastic-Gears.webp\" alt=\"MC nylon cast polyamide large gear industrial Korea Ever-Power heavy load\" \/><figcaption style=\"font-size: 12.5px; color: #64748b; margin-top: 10px; padding: 8px 14px; border-left: 4px solid #f97316; background: #fff; line-height: 1.65;\">Korea Ever-Power MC nylon (monomer cast polyamide 6) gear range for heavy-load industrial applications \u2014 from M6 oil-filled MC nylon gears for crane bridge auxiliary drives (foreground, OD 300 mm, blue-grey colour of the natural MC nylon + oil-filled compounding) to M12 natural MC nylon gears for concrete mixer ring drive auxiliary positions (background, OD 600 mm, pale blue-grey). The distinguishing visual characteristic of MC nylon compared to injection moulded nylon is the uniformity of colour through the full cross-section \u2014 injection moulded nylon shows a darker skin layer (the rapidly cooled amorphous skin) and a lighter core; MC nylon has a uniform colour throughout because the polymerisation occurs uniformly from the billet surface inward. Korea Ever-Power\u2019s quality inspection includes a cross-section colour check on one billet per casting batch to confirm this uniformity \u2014 a billet showing a dark skin layer more than 5 mm thick indicates an incomplete polymerisation cycle and is rejected. All MC nylon billets are tested for tensile strength and flexural modulus on test specimens cut from the billet top (the last section to polymerise, typically the least crystalline zone) before the billet is approved for gear machining.<\/figcaption><\/figure>\n<\/section>\n<section style=\"margin: 64px 0 0;\">\n<h2 style=\"font-size: clamp(18px,2.6vw,24px); font-weight: 800; color: #1c2330; margin: 0 0 20px; padding-bottom: 10px; border-bottom: 3px solid #2563a8;\">MC Nylon Heavy-Load Gear Application Specifications<\/h2>\n<div style=\"display: flex; flex-wrap: wrap; gap: 16px; margin: 0 0 28px;\">\n<div style=\"flex: 1 1 220px; background: #fff; border: 1px solid #d1d9e6; border-top: 4px solid #2563a8; border-radius: 4px; padding: 20px 22px;\">\n<h3 style=\"font-size: 14px; font-weight: 800; color: #1c2330; margin: 0 0 12px;\">Crane Bridge and Hoist Auxiliary Drives<\/h3>\n<p style=\"font-size: 13.5px; color: #4b5768; line-height: 1.72; margin: 0 0 12px;\">Oil-filled MC nylon, M8\u2013M12, OD 300\u2013600 mm, face width 60\u2013120 mm, bore 40\u2013120 mm, slow speed (10\u201350 RPM output), intermittent duty (crane hoist cycles). Crane bridge and overhead crane auxiliary drives (the secondary reduction stages between the main gearbox and the wheel axle, or the auxiliary drives for the festoon cable reel and the limit switch gear train) are a high-volume application for MC nylon gears in steel manufacturing plants, paper mills, and warehouse distribution centres \u2014 environments where the crane operates in a humid, corrosive, or dusty atmosphere that would require frequent painting and maintenance of equivalent steel gears. The oil-filled MC nylon gear in an overhead crane auxiliary drive requires no lubrication maintenance (the internal oil provides the boundary film for the lifetime of the gear tooth), tolerates the corrosive atmosphere without surface degradation, and reduces the gear mesh noise in the crane hall by 10\u201315 dB(A) compared to equivalent steel gears \u2014 a meaningful contribution to the overall noise level in a manned crane operation area. Korea Ever-Power crane bridge MC nylon gears are machined with a hub bore to H7 tolerance for press or clearance fit onto the drive shaft, and with a keyway to DIN 6885 standard for the key engagement with the shaft flat \u2014 the keyway is machined in the same CNC turning setup as the bore, ensuring concentricity of the keyway to the bore axis within 0.05 mm TIR.<\/p>\n<p style=\"font-size: 12px; font-weight: bold; color: #2563a8; margin: 0;\">Oil-filled MC \u00b7 M8\u2013M12 \u00b7 300\u2013600mm \u00b7 no lube maintenance<\/p>\n<\/div>\n<div style=\"flex: 1 1 220px; background: #fff; border: 1px solid #d1d9e6; border-top: 4px solid #f97316; border-radius: 4px; padding: 20px 22px;\">\n<h3 style=\"font-size: 14px; font-weight: 800; color: #1c2330; margin: 0 0 12px;\">Mining and Chemical Plant Drives (Anti-Static)<\/h3>\n<p style=\"font-size: 13.5px; color: #4b5768; line-height: 1.72; margin: 0 0 12px;\">Anti-static MC nylon (AS grade, surface resistivity \u2264 10\u2076 \u03a9), M6\u2013M12, OD 200\u2013500 mm, surface resistivity measured and certified per EN 13463-1 (non-electrical equipment for potentially explosive atmospheres). Mining (coal, grain, flour, wood dust) and chemical plant (flammable solvent vapour) drives require that any electrical charge accumulated on the rotating gear tooth surface from the gear mesh friction is dissipated to ground before it reaches the discharge threshold \u2014 the minimum ignition energy of coal dust in air is approximately 30 mJ, and a PVC or standard nylon gear at 100 RPM can accumulate 50\u2013100 mJ of charge over several rotations without a discharge path. The anti-static MC nylon gear (with conductive carbon black compounded into the casting) has surface resistivity below 10\u2076 \u03a9 \u2014 any charge accumulated at the tooth surface drains to ground through the conductive gear body and the shaft bearing before reaching the ignition threshold. Korea Ever-Power anti-static MC nylon gears are supplied with an individual surface resistivity measurement certificate (measured on the gear OD and tooth surface after machining) confirming compliance with the \u2264 10\u2076 \u03a9 requirement for ATEX\/IECEx Zone 2 and Zone 21 (combustible dust) drive applications.<\/p>\n<p style=\"font-size: 12px; font-weight: bold; color: #f97316; margin: 0;\">AS-grade \u00b7 \u226410\u2076\u03a9 \u00b7 ATEX Zone 21 \u00b7 certified<\/p>\n<\/div>\n<div style=\"flex: 1 1 220px; background: #fff; border: 1px solid #d1d9e6; border-top: 4px solid #1c2330; border-radius: 4px; padding: 20px 22px;\">\n<h3 style=\"font-size: 14px; font-weight: 800; color: #1c2330; margin: 0 0 12px;\">Paper Mill Spreader and Felt Roll Drives<\/h3>\n<p style=\"font-size: 13.5px; color: #4b5768; line-height: 1.72; margin: 0 0 12px;\">Natural or oil-filled MC nylon, M5\u2013M8, OD 150\u2013350 mm, face width 50\u201380 mm, chemical resistance to paper mill white water (pH 4.5\u20138.5, 40\u201370\u00b0C), continuous duty at 30\u2013200 RPM. Paper mill drives \u2014 the felt roll drives, spreader bar drives, calender auxiliary drives, and coater metering drives \u2014 operate in one of the most chemically aggressive environments in heavy industry: white water (the aqueous medium that carries the paper fibres on the paper machine) contains acidic or alkaline pH, mineral fillers (clay, calcium carbonate, TiO\u2082), fibre fragments, and biocide chemicals that cause rapid corrosion of unprotected steel gear surfaces and require regular maintenance of painted or galvanised steel alternative components. MC nylon gears in paper mill drives eliminate the corrosion maintenance entirely \u2014 the PA6 polymer is chemically resistant to white water across the pH range of 4.5\u20138.5 and to the biocide chemicals (glutaraldehyde, isothiazolinone-based) used in the paper machine white water circuit. Korea Ever-Power paper mill MC nylon gears are supplied with a chemical resistance confirmation for the customer\u2019s specific white water chemistry if provided \u2014 the standard MC nylon grade resists all white water chemicals at the concentrations used in standard paper machine water treatment.<\/p>\n<p style=\"font-size: 12px; font-weight: bold; color: #1c2330; margin: 0;\">Natural MC \u00b7 pH 4.5\u20138.5 \u00b7 white water resistant<\/p>\n<\/div>\n<\/div>\n<figure style=\"margin: 0 0 28px;\"><img decoding=\"async\" style=\"width: 100%; height: auto; display: block; border-radius: 6px; border: 1px solid #d1d9e6;\" title=\"Korea Ever-Power MC Nylon Large Gear Machining\" src=\"https:\/\/gearrack.top\/wp-content\/uploads\/2026\/07\/Ever-Power-workshop-2.webp\" alt=\"Korea Ever-Power MC nylon cast gear large diameter machining industrial\" \/><figcaption style=\"font-size: 12.5px; color: #64748b; margin-top: 10px; padding: 8px 14px; border-left: 4px solid #2563a8; background: #fff; line-height: 1.65;\">Korea Ever-Power MC nylon large gear machining \u2014 hobbing of a M10 MC nylon gear from a 600 mm OD cast billet on a CNC vertical hobbing machine. MC nylon machines with cutting parameters significantly different from steel: higher cutting speeds (150\u2013300 m\/min peripheral velocity at the hob vs 30\u201360 m\/min for steel), very low feed rates (0.15\u20130.25 mm\/rev vs 1\u20133 mm\/rev for steel) to prevent the nylon from melting at the cutting zone, and dry cutting without coolant (cutting fluid absorption would cause the gear to swell during the machining operation, invalidating the tooth dimensions). The chips from MC nylon hobbing are long, continuous curls (unlike the short chips from steel hobbing) that must be cleared continuously from the cutting zone by a directed compressed air blast \u2014 chips allowed to accumulate at the hob contact can become entangled in the hob flutes and produce a tooth surface defect as they are re-cut. Korea Ever-Power uses a specifically designed chip extraction system on all MC nylon gear hobbing machines: a combination of compressed air blast at the hob cutting zone and a vacuum extraction port at the chip fall zone below the work table, preventing chip re-cutting and maintaining a clean cutting environment for the full cycle time of a large-OD MC nylon gear (which can be 4\u201312 hours of continuous hobbing for OD 400\u2013600 mm at M8\u2013M12).<\/figcaption><\/figure>\n<\/section>\n<figure style=\"margin: 0 0 28px;\"><img decoding=\"async\" style=\"width: 100%; height: auto; display: block; border-radius: 6px; border: 1px solid #d1d9e6;\" title=\"MC Nylon Heavy Load Industrial Gear Range \u2014 Korea Ever-Power\" src=\"https:\/\/gearrack.top\/wp-content\/uploads\/2026\/07\/types-of-gears-2.webp\" alt=\"MC nylon heavy load gear types industrial Korea Ever-Power range\" \/><figcaption style=\"font-size: 12.5px; color: #64748b; margin-top: 10px; padding: 8px 14px; border-left: 4px solid #f97316; background: #fff; line-height: 1.65;\">Korea Ever-Power gear type range for heavy industrial applications \u2014 showing the spectrum from steel gears (in the high-load, precision end of the range) to MC nylon cast gears (in the large-OD, noise-sensitive, corrosion-resistant end of the range). The choice between steel and MC nylon for a heavy industrial drive does not depend on absolute size or absolute load \u2014 a M12 steel gear at OD 600 mm and a M12 MC nylon gear at the same OD serve fundamentally different applications: the steel gear where the load is high relative to the OD (giving a small safety factor that requires the full strength of steel), and the MC nylon gear where the load is low relative to the OD (giving a large safety factor even in MC nylon) and the material selection is driven by corrosion resistance, noise, self-lubrication, or ATEX requirements. The crossover point \u2014 the load at which MC nylon becomes structurally inadequate and steel becomes necessary \u2014 depends on the specific application, and Korea Ever-Power\u2019s VDI 2736 calculation service answers this question definitively for any enquiry: provide the OD, module, tooth count, and application torque, and Korea Ever-Power will calculate whether the load is within the MC nylon design envelope or whether a steel gear is required.<\/figcaption><\/figure>\n<section style=\"margin: 64px 0 0;\">\n<h2 style=\"font-size: clamp(18px,2.6vw,24px); font-weight: 800; color: #1c2330; margin: 0 0 24px; padding-bottom: 10px; border-bottom: 3px solid #2563a8;\">Frequently Asked Questions \u2014 MC Nylon Heavy-Load Gears<\/h2>\n<div style=\"display: flex; flex-direction: column; gap: 12px;\">\n<div style=\"background: #fff; border: 1px solid #d1d9e6; border-radius: 4px; overflow: hidden;\">\n<div style=\"padding: 16px 20px; display: flex; align-items: flex-start; gap: 14px; background: #f7f9fc; border-bottom: 1px solid #e8edf4;\"><span style=\"background: #1c2330; color: #f97316; font-size: 10px; font-weight: 800; padding: 3px 10px; border-radius: 2px; white-space: nowrap; letter-spacing: 1px;\">Q 01<\/span><\/p>\n<p style=\"font-size: 14.5px; font-weight: bold; color: #1c2330; line-height: 1.35; margin: 0;\">We want to replace the M10 steel gears on an overhead crane bridge drive with MC nylon to reduce noise in our automotive production plant. The crane lifts up to 8 tonnes. What gear dimensions and safety factors should we check before making the switch?<\/p>\n<\/div>\n<div style=\"padding: 18px 20px;\">\n<p style=\"font-size: 14.5px; color: #374151; line-height: 1.78; margin: 0;\">Replacing M10 steel crane bridge drive gears with oil-filled MC nylon is a well-established practice in European automotive and steel plants, and Korea Ever-Power has supplied this replacement for several crane builders in Germany and the Netherlands. The safety factor check before confirming the material switch: (1) <strong>Output torque at the crane bridge drive gear:<\/strong> an 8-tonne crane lifting at 0.1 m\/s with a drum diameter of 300 mm produces a hoisting torque of 8,000 \u00d7 9.81 \u00d7 0.15 = 11,772 N\u00b7m at the drum. If the bridge drive reduction is separate from the hoist (which it usually is \u2014 the bridge traversal and the hoist are independent drives), the bridge drive torque is determined by the bridge travel force (typically 1\u20133% of the crane weight \u00d7 gravity \u00d7 wheel radius), not the lifted load. For a 5,000 kg crane bridge at 3% rolling resistance: F = 0.03 \u00d7 5,000 \u00d7 9.81 = 1,471 N; at 250 mm wheel radius: T_bridge = 1,471 \u00d7 0.25 = 368 N\u00b7m at the wheel axle. If the M10 gear is the last reduction stage at, say, 5:1 ratio, the input torque to that stage is 368\/5 = 73.6 N\u00b7m. (2) <strong>MC nylon tooth bending safety factor at 73.6 N\u00b7m, M10:<\/strong> for a M10, 30T MC nylon gear with 60 mm face width, the VDI 2736 bending stress is approximately \u03c3_F = F_t \u00d7 YF \u00d7 YS \/ (b \u00d7 m) = (73,600\/0.15) \u00d7 1.6 \u00d7 1.0 \/ (60 \u00d7 10) = 490,667\/600 = 817 N\/mm\u00b2 \u2014 wait, this exceeds the MC nylon bending strength. Recalculate: F_t = T\/r = 73,600\/0.15 m = 490 N. \u03c3_F = (490 \u00d7 1.6 \u00d7 1.0) \/ (60 \u00d7 10) = 784\/600 = 1.31 MPa. The MC nylon bending fatigue stress limit at 10\u2076 cycles: approximately 12\u201316 MPa. Safety factor S_F = 12\/1.31 = 9.2 \u2014 very comfortable. (3) <strong>Contact fatigue check:<\/strong> equally comfortable at these torques. The MC nylon gear will handle the 8-tonne crane bridge drive load with large safety margins. Korea Ever-Power performs the complete VDI 2736 calculation as part of every MC nylon replacement gear quotation \u2014 provide the gear OD, tooth count, face width, and the application torque for a confirmed calculation within 3 working days.<\/p>\n<\/div>\n<\/div>\n<div style=\"background: #fff; border: 1px solid #d1d9e6; border-radius: 4px; overflow: hidden;\">\n<div style=\"padding: 16px 20px; display: flex; align-items: flex-start; gap: 14px; background: #f7f9fc; border-bottom: 1px solid #e8edf4;\"><span style=\"background: #1c2330; color: #f97316; font-size: 10px; font-weight: 800; padding: 3px 10px; border-radius: 2px; white-space: nowrap; letter-spacing: 1px;\">Q 02<\/span><\/p>\n<p style=\"font-size: 14.5px; font-weight: bold; color: #1c2330; line-height: 1.35; margin: 0;\">How does Korea Ever-Power verify that the anti-static MC nylon used in an ATEX Zone 21 coal handling drive complies with the surface resistivity requirement, and what certification documentation is provided?<\/p>\n<\/div>\n<div style=\"padding: 18px 20px;\">\n<p style=\"font-size: 14.5px; color: #374151; line-height: 1.78; margin: 0;\">Korea Ever-Power\u2019s anti-static MC nylon gear verification and certification process for ATEX Zone 21 applications: <strong>Material-level verification:<\/strong> the AS-grade MC nylon billet is manufactured with a compounded carbon black content (typically 2\u20134% by weight) that provides the required conductivity. The billet resistivity is measured before machining using a two-electrode method per IEC 62631-3-1 at 5 positions on the billet outer surface \u2014 this confirms the casting has achieved uniform conductivity throughout the billet before any gear machining is performed. Acceptance criterion: volume resistivity \u2264 10\u2078 \u03a9\u00b7cm (equivalent to surface resistivity \u2264 10\u2078 \u03a9 on the billet surface). <strong>Finished gear verification:<\/strong> after machining, the finished gear is measured for surface resistivity on the tooth flank surface (the surface that will be in tribological contact with the mating gear) and on the bore and OD faces (the surfaces that will contact the shaft and housing). The measurement uses the method of EN 1149-1 (surface resistance measurement for electrostatic properties of protective clothing \u2014 the same measurement principle is applicable to engineering components). Acceptance criterion for Zone 21 coal dust: surface resistivity \u2264 10\u2076 \u03a9 (the IECEx criterion for components in Zone 21 combustible dust environments per IEC 60079-31). <strong>Documentation provided:<\/strong> (1) Material certificate confirming AS-grade compounding and carbon black content from the polymer supplier; (2) Billet resistivity measurement report (pre-machining); (3) Finished gear surface resistivity measurement report on the gear OD, tooth flanks, and bore, with individual measurement values at 4 positions; (4) Korea Ever-Power declaration of conformance stating the gear complies with the surface resistivity requirement for ATEX Zone 21 \/ IECEx Zone 21 use per IEC 60079-31 (non-electrical equipment category). Note: Korea Ever-Power\u2019s documentation supports the machine builder\u2019s own ATEX certification process \u2014 Korea Ever-Power does not independently hold ATEX product certification (which would require third-party notified body involvement), but provides all the material and measurement data needed for the machine builder\u2019s technical documentation submission to the notified body.<\/p>\n<\/div>\n<\/div>\n<div style=\"background: #fff; border: 1px solid #d1d9e6; border-radius: 4px; overflow: hidden;\">\n<div style=\"padding: 16px 20px; display: flex; align-items: flex-start; gap: 14px; background: #f7f9fc; border-bottom: 1px solid #e8edf4;\"><span style=\"background: #1c2330; color: #f97316; font-size: 10px; font-weight: 800; padding: 3px 10px; border-radius: 2px; white-space: nowrap; letter-spacing: 1px;\">Q 03<\/span><\/p>\n<p style=\"font-size: 14.5px; font-weight: bold; color: #1c2330; line-height: 1.35; margin: 0;\">What is the expected service life of an oil-filled MC nylon gear in a crane bridge auxiliary drive, and what are the visual signs that indicate it needs replacement before tooth fracture?<\/p>\n<\/div>\n<div style=\"padding: 18px 20px;\">\n<p style=\"font-size: 14.5px; color: #374151; line-height: 1.78; margin: 0;\">Expected service life of oil-filled MC nylon in a crane bridge auxiliary drive: based on Korea Ever-Power&#8217;s field experience and customer feedback from European industrial crane applications, oil-filled MC nylon M10 gears in overhead crane bridge drives at the loads typical for 5\u201320 tonne cranes (bridge drive torques of 100\u2013500 N\u00b7m at the MC nylon gear) achieve 10\u201320 years of service life before replacement \u2014 significantly longer than the equivalent steel gears would require (steel auxiliary drive gears in crane bridge applications corrode and wear in the typically humid crane hall environment, requiring replacement every 5\u20138 years). The service life variation is wide because it depends on the crane utilisation (hours per day, starts per hour) and the bridge drive torque relative to the gear design safety factor \u2014 a crane used for 2 starts per hour (light crane application) at 30% of the calculated design torque will achieve the upper end of the life range; a crane used for 15 starts per hour (heavy crane, continuous operation) at 80% of design torque will achieve the lower end. <strong>Visual replacement indicators \u2014 inspect at each annual crane maintenance:<\/strong> (1) <strong>Tooth tip wear:<\/strong> measure the tip diameter of 5 teeth evenly spaced around the gear and compare to the new-condition tip diameter. A reduction of more than 10% of the original tip height (e.g. tip height reduced from 10 mm to 9 mm for M10 gear) indicates significant wear \u2014 replace before the tip wear reaches 15% of tip height, at which point the tooth form becomes non-involute and gear mesh efficiency drops sharply. (2) <strong>Tooth root cracking:<\/strong> inspect the tooth root zone (the transition between the tooth flank and the gear body) using a 5\u00d7 magnifying glass. Visible cracks propagating from the root fillet radius indicate bending fatigue accumulation \u2014 replace immediately if root cracks are found, as these can propagate to tooth fracture within 100\u2013500 operating cycles. (3) <strong>Surface softening or deformation:<\/strong> press a thumbnail into the tooth flank surface \u2014 if the tooth surface leaves a permanent impression under thumbnail pressure (which requires roughly 5 N force), the gear surface has softened, indicating the tooth surface temperature has exceeded the MC nylon service limit. Reduce the drive torque or improve ventilation around the gear, and replace the gear at the next scheduled maintenance. (4) <strong>Oil-film depletion (oil-filled grade):<\/strong> a new oil-filled MC nylon gear has a slight oily sheen on the tooth flank surface when pressed with a tissue paper. After 10+ years of service, the internal oil may be partially depleted \u2014 if the tissue paper test shows no oil transfer and the tooth flanks appear dry, apply a light surface coat of mineral gear oil (SAE 90 or equivalent) and monitor wear rate \u2014 the gear can continue in service with surface lubrication if the tooth flanks are still within the tip-height and root-crack criteria above.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n<section style=\"margin: 72px 0 0;\">\n<div style=\"text-align: center; margin-bottom: 28px;\">\n<h2 style=\"font-size: clamp(17px,2.2vw,21px); font-weight: 800; color: #1c2330; margin: 0 0 8px;\">Explore Korea Ever-Power Gear Categories<\/h2>\n<p style=\"font-size: 14px; color: #64748b; margin: 0;\">Seven precision gear product lines for heavy industrial drives, crane systems, paper mills, mining equipment, and chemical plant machinery worldwide.<\/p>\n<\/div>\n<div style=\"display: flex; flex-wrap: wrap; gap: 16px;\">\n<div style=\"flex: 1 1 140px; max-width: 220px; border: 1px solid #d1d9e6; border-bottom: 3px solid #2563a8; border-radius: 6px; overflow: hidden; background: #fff;\"><img decoding=\"async\" style=\"width: 100%; height: 130px; object-fit: cover; display: block;\" src=\"https:\/\/gearrack.top\/wp-content\/uploads\/2026\/07\/Steel-Spur-Gear.webp\" alt=\"industrial spur gear heavy\" \/><\/p>\n<div style=\"padding: 10px 14px;\">\n<p style=\"font-size: 13px; font-weight: bold; color: #1c2330; margin: 0 0 3px;\"><a style=\"color: #1c2330; text-decoration: none;\" href=\"https:\/\/gearrack.top\/ja\/product-category\/spur-gear\/\">Spur Gears<\/a><\/p>\n<p style=\"font-size: 12px; color: #64748b; margin: 0; line-height: 1.5;\">Heavy industrial \u00b7 crane \u00b7 large M<\/p>\n<\/div>\n<\/div>\n<div style=\"flex: 1 1 140px; max-width: 220px; border: 1px solid #d1d9e6; border-bottom: 3px solid #1c2330; border-radius: 6px; overflow: hidden; background: #fff;\"><img decoding=\"async\" style=\"width: 100%; height: 130px; object-fit: cover; display: block;\" src=\"https:\/\/gearrack.top\/wp-content\/uploads\/2026\/07\/Heavy-Machinery-Double-Helical-Gear.webp\" alt=\"heavy helical gear industrial\" \/><\/p>\n<div style=\"padding: 10px 14px;\">\n<p style=\"font-size: 13px; font-weight: bold; color: #1c2330; margin: 0 0 3px;\"><a style=\"color: #1c2330; text-decoration: none;\" href=\"https:\/\/gearrack.top\/ja\/product-category\/helical-gear\/\">Helical Gears<\/a><\/p>\n<p style=\"font-size: 12px; color: #64748b; margin: 0; line-height: 1.5;\">Heavy industry \u00b7 paper mill \u00b7 crane<\/p>\n<\/div>\n<\/div>\n<div style=\"flex: 1 1 140px; max-width: 220px; border: 1px solid #d1d9e6; border-bottom: 3px solid #f97316; border-radius: 6px; overflow: hidden; background: #fff;\"><img decoding=\"async\" style=\"width: 100%; height: 130px; object-fit: cover; display: block;\" src=\"https:\/\/gearrack.top\/wp-content\/uploads\/2026\/07\/Forging-Bevel-Gears.webp\" alt=\"bevel gear industrial heavy\" \/><\/p>\n<div style=\"padding: 10px 14px;\">\n<p style=\"font-size: 13px; font-weight: bold; color: #1c2330; margin: 0 0 3px;\"><a style=\"color: #1c2330; text-decoration: none;\" href=\"https:\/\/gearrack.top\/ja\/product-category\/bevel-gears\/\">\u30d9\u30d9\u30eb\u30ae\u30a2<\/a><\/p>\n<p style=\"font-size: 12px; color: #64748b; margin: 0; line-height: 1.5;\">Industrial angle drive \u00b7 heavy duty<\/p>\n<\/div>\n<\/div>\n<div style=\"flex: 1 1 140px; max-width: 220px; border: 1px solid #d1d9e6; border-bottom: 3px solid #2563a8; border-radius: 6px; overflow: hidden; background: #fff;\"><img decoding=\"async\" style=\"width: 100%; height: 130px; object-fit: cover; display: block;\" src=\"https:\/\/gearrack.top\/wp-content\/uploads\/2026\/07\/Worm-and-Wheel.webp\" alt=\"worm gear industrial\" \/><\/p>\n<div style=\"padding: 10px 14px;\">\n<p style=\"font-size: 13px; font-weight: bold; color: #1c2330; margin: 0 0 3px;\"><a style=\"color: #1c2330; text-decoration: none;\" href=\"https:\/\/gearrack.top\/ja\/product-category\/worm-gear\/\">Worm Gears<\/a><\/p>\n<p style=\"font-size: 12px; color: #64748b; margin: 0; line-height: 1.5;\">Industrial self-lock \u00b7 crane hoist<\/p>\n<\/div>\n<\/div>\n<div style=\"flex: 1 1 140px; max-width: 220px; border: 1px solid #d1d9e6; border-bottom: 3px solid #1c2330; border-radius: 6px; overflow: hidden; background: #fff;\"><img decoding=\"async\" style=\"width: 100%; height: 130px; object-fit: cover; display: block;\" src=\"https:\/\/gearrack.top\/wp-content\/uploads\/2026\/07\/Ring-Gear-For-Cement-Mixer.webp\" alt=\"ring gear industrial heavy\" \/><\/p>\n<div style=\"padding: 10px 14px;\">\n<p style=\"font-size: 13px; font-weight: bold; color: #1c2330; margin: 0 0 3px;\"><a style=\"color: #1c2330; text-decoration: none;\" href=\"https:\/\/gearrack.top\/ja\/product-category\/ring-gear\/\">Ring Gears<\/a><\/p>\n<p style=\"font-size: 12px; color: #64748b; margin: 0; line-height: 1.5;\">Industrial ring \u00b7 large OD \u00b7 M10\u2013M50<\/p>\n<\/div>\n<\/div>\n<div style=\"flex: 1 1 140px; max-width: 220px; border: 1px solid #d1d9e6; border-bottom: 3px solid #f97316; border-radius: 6px; overflow: hidden; background: #fff;\"><img decoding=\"async\" style=\"width: 100%; height: 130px; object-fit: cover; display: block;\" src=\"https:\/\/gearrack.top\/wp-content\/uploads\/2026\/07\/Planetary-Gear-Sets.webp\" alt=\"planetary gear industrial\" \/><\/p>\n<div style=\"padding: 10px 14px;\">\n<p style=\"font-size: 13px; font-weight: bold; color: #1c2330; margin: 0 0 3px;\"><a style=\"color: #1c2330; text-decoration: none;\" href=\"https:\/\/gearrack.top\/ja\/product-category\/planetary-gear\/\">Planetary Gears<\/a><\/p>\n<p style=\"font-size: 12px; color: #64748b; margin: 0; line-height: 1.5;\">Industrial reducer \u00b7 crane hoist kit<\/p>\n<\/div>\n<\/div>\n<div style=\"flex: 1 1 140px; max-width: 220px; border: 1px solid #d1d9e6; border-bottom: 3px solid #475569; border-radius: 6px; overflow: hidden; background: #fff;\"><img decoding=\"async\" style=\"width: 100%; height: 130px; object-fit: cover; display: block;\" src=\"https:\/\/gearrack.top\/wp-content\/uploads\/2026\/07\/Plastic-Gears.webp\" alt=\"MC nylon plastic gear heavy\" \/><\/p>\n<div style=\"padding: 10px 14px;\">\n<p style=\"font-size: 13px; font-weight: bold; color: #1c2330; margin: 0 0 3px;\"><a style=\"color: #1c2330; text-decoration: none;\" href=\"https:\/\/gearrack.top\/ja\/product-category\/plastic-gear\/\">Plastic Gears<\/a><\/p>\n<p style=\"font-size: 12px; color: #64748b; margin: 0; line-height: 1.5;\">MC Nylon \u00b7 oil-fill \u00b7 AS \u00b7 M5\u2013M20<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n<div style=\"margin: 64px 0 72px; background: #1c2330; border-radius: 6px; padding: clamp(30px,5vw,50px) clamp(24px,4vw,48px); position: relative; overflow: hidden;\">\n<div style=\"position: absolute; top: 0; right: 0; width: 220px; height: 220px; border: 44px solid rgba(37,99,168,0.15); border-radius: 50%; transform: translate(60px,-60px); pointer-events: none;\"><\/div>\n<p style=\"font-size: 9px; font-weight: 800; letter-spacing: 3px; text-transform: uppercase; color: #f97316; margin: 0 0 12px; position: relative; z-index: 1;\">GET A QUOTATION \u00b7 KOREA EVER-POWER<\/p>\n<h2 style=\"font-size: clamp(18px,2.8vw,26px); font-weight: 900; color: #fff; margin: 0 0 12px; line-height: 1.2; position: relative; z-index: 1;\">Need MC Nylon Gears for Heavy Industrial Applications?<\/h2>\n<p style=\"font-size: 14.5px; color: #8fa3bf; margin: 0 0 24px; max-width: 580px; line-height: 1.7; position: relative; z-index: 1;\">Korea Ever-Power manufactures MC nylon heavy-load gears from in-house cast billets \u2014 natural, oil-filled (8% mineral oil), and anti-static (AS grade, \u226410\u2076\u03a9 certified). M5\u2013M20, OD 100\u2013800 mm, machined from billet to OEM drawing. Crane, paper mill, chemical plant, and mining applications. ATEX Zone 21 surface resistivity measurement certificate. VDI 2736 gear capacity analysis included. Minimum 1 piece. Lead time 10\u201325 days. ISO 9001:2015 certified.<\/p>\n<p><a style=\"display: inline-block; background: #f97316; color: #fff; padding: 14px 32px; border-radius: 3px; text-decoration: none; font-weight: 800; font-size: 14px; letter-spacing: 0.5px; text-transform: uppercase; position: relative; z-index: 1;\" href=\"https:\/\/gearrack.top\/ja\/contact\/\">Request a Quotation \u2192<\/a><\/p>\n<\/div>\n<p style=\"text-align: right;\"><em>\u7de8\u96c6\u8005: Cxm<\/em><\/p>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>GEAR APPLICATION GUIDE \u00b7 PLASTIC GEAR \u00b7 PL05 MC Nylon Gears for Heavy-Load Industrial Applications: Cast Polyamide Gear Drives, Large-Module Plastic Gears and Anti-Static MC Nylon MC nylon \u2014 monomer cast polyamide 6, manufactured by casting liquid caprolactam directly into a mould rather than injection moulding pre-polymerised pellets \u2014 produces a plastic gear blank with a degree of crystallinity 5\u201315% higher than injection moulded PA6, significantly lower residual stress, and a much larger achievable part size than injection moulding permits. These properties make MC nylon the material of choice for large-diameter, heavy-load plastic gears (OD above 200 mm, face width above 50 mm) in industrial drives where the economics of [&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":[4566],"tags":[],"class_list":["post-2052","post","type-post","status-publish","format-standard","hentry","category-application-of-gears"],"_links":{"self":[{"href":"https:\/\/gearrack.top\/ja\/wp-json\/wp\/v2\/posts\/2052","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gearrack.top\/ja\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gearrack.top\/ja\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gearrack.top\/ja\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gearrack.top\/ja\/wp-json\/wp\/v2\/comments?post=2052"}],"version-history":[{"count":1,"href":"https:\/\/gearrack.top\/ja\/wp-json\/wp\/v2\/posts\/2052\/revisions"}],"predecessor-version":[{"id":2054,"href":"https:\/\/gearrack.top\/ja\/wp-json\/wp\/v2\/posts\/2052\/revisions\/2054"}],"wp:attachment":[{"href":"https:\/\/gearrack.top\/ja\/wp-json\/wp\/v2\/media?parent=2052"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gearrack.top\/ja\/wp-json\/wp\/v2\/categories?post=2052"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gearrack.top\/ja\/wp-json\/wp\/v2\/tags?post=2052"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}