Flexible Gear Coupling Manufacturer in India
Super Mech Industries manufactures flexible gear couplings — full gear and half gear types — from FG-100 (559 Nm) to FG-119 (1,666,744 Nm). Standard sizes in stock. Custom bore machined in 3–5 days. ISO 9001:2015 certified.
Quick Specifications
Size rangeFG-100 through FG-119 (20 sizes)Torque range559 – 1,666,744 Nm (57 – 169,961 Kg.M)TypesFull gear coupling, Half gear couplingMaterialsEN8 steel hubs as standard; EN9 on requestBore rangePilot bore 13 mm; finished bores up to 710 mmMax speed500 – 7,600 rpm (size dependent)LubricationEP2 lithium-complex grease NLGI Grade 2DispatchSame week (stock sizes) · 3–5 days (custom bore)What Is a Flexible Gear Coupling?
A flexible gear coupling transmits torque between two rotating shafts while accommodating angular, parallel, and axial misalignment — using crowned gear teeth that mesh between an inner hub and an outer grease-filled sleeve.
Torque Transmission
Transmits full rated torque continuously without slip. Crown-tooth design maintains full mesh engagement across the misalignment range.
Misalignment Tolerance
Accommodates angular (±1.5°), parallel (0.75 mm), and axial misalignment simultaneously within rated limits.
Shock Load Damping
Crowned teeth distribute peak shock loads across the full tooth face rather than concentrating stress at the edges.
Low Maintenance
Only scheduled maintenance is re-greasing every 2,000–3,000 hours. No rubber elements, no spider inserts, no wear bushes to replace.
SMI manufactures in two configurations: full gear couplings (both hubs flexible) and half gear couplings (one hub flexible, one rigid flange).
Full Gear vs Half Gear — Which Do You Need?
The choice depends on the flexibility requirement at each shaft end. Both configurations are manufactured by SMI with identical crown-tooth gear mesh quality.
| Feature | Full Gear Coupling | Half Gear Coupling |
|---|---|---|
| Hub configuration | Both hubs have crowned gear teeth (both flexible) | One hub has gear teeth; one hub is a rigid flange |
| Angular misalignment | Up to 1.5° per coupling half (total ±3°) | Up to 1.5° total across the coupling |
| Parallel offset | Up to 0.75 mm | Up to 0.50 mm |
| Axial float | ±6 – 15 mm (thermal growth allowance) | ±4 – 8 mm |
| Typical application | Rolling mills, compressors, heavy conveyors, mining | Pumps, fans, gearboxes with rigid motor shaft |
| Dismantling | Sleeve slides off; hubs stay on shafts | Access one shaft without disturbing the other |
Size & Torque Specifications
Standard catalogue sizes. All sizes available with custom bore diameters and keyway dimensions within the maximum bore limit.
| Size | Torque (Kg.M) | Torque (Nm) | Pilot Bore PB (mm) | Max Bore D1 (mm) | Max Speed (rpm) |
|---|---|---|---|---|---|
| FG-100 | 57 | 559 | 13 | 35 | 7,600 |
| FG-101 | 115 | 1,127 | 21 | 50 | 6,300 |
| FG-102 | 286 | 2,804 | 30 | 60 | 5,000 |
| FG-103 | 515 | 5,047 | 40 | 75 | 4,000 |
| FG-104 | 975 | 9,557 | 50 | 90 | 3,350 |
| FG-105 | 1,489 | 14,605 | 60 | 110 | 2,800 |
| FG-106 | 2,289 | 22,444 | 75 | 125 | 2,500 |
| FG-107 | 4,008 | 39,303 | 90 | 140 | 2,100 |
| FG-108 | 5,147 | 50,472 | 105 | 160 | 1,900 |
| FG-109 | 6,406 | 62,821 | 125 | 180 | 1,700 |
| FG-110 | 9,374 | 91,923 | 140 | 220 | 1,400 |
| FG-111 | 12,549 | 123,065 | 160 | 260 | 1,250 |
| FG-112 | 16,776 | 164,516 | 180 | 300 | 1,120 |
| FG-113 | 22,821 | 223,793 | 200 | 330 | 1,000 |
| FG-114 | 32,632 | 320,012 | 220 | 370 | 900 |
| FG-115 | 39,640 | 388,738 | 250 | 410 | 800 |
| FG-116 | 68,440 | 671,165 | 300 | 455 | 710 |
| FG-117 | 97,349 | 954,665 | 375 | 520 | 630 |
| FG-118 | 128,886 | 1,263,938 | 450 | 610 | 560 |
| FG-119 | 169,961 | 1,666,744 | 520 | 710 | 500 |
Ratings at ambient temperature 40°C, standard EP2 grease. For speeds above max rated or temps above 60°C, consult SMI — call +91 63510 70577.
Industries We Serve
Flexible gear couplings are the preferred choice wherever high torque, shaft misalignment, and shock loads combine — which describes most of India's heavy industries.
Steel Rolling Mills
Main drive couplings between motor and gearbox, and gearbox to roll neck. High shock load, heavy misalignment from thermal growth.
Cement Plants
Kiln drive couplings, clinker crusher drives, ball mill drives. Heavy cyclic torque — the larger sizes are most common.
Paper & Pulp Mills
Calendar roll drives and refiner drives. Uniform load, precision speed — smaller and mid-range sizes.
Chemical & Petrochemical
Pump and compressor drives in corrosive environments. Stainless-grade sleeve options available.
Power Generation
Cooling tower fan drives, boiler feed pump drives, turbine auxiliary drives.
Mining & Mineral Processing
Conveyor drives, crusher drives, slurry pump drives. High shock — SF 2.0–2.5 applied.
Why Choose SMI
As a Gujarat-based manufacturer, SMI combines factory-direct pricing with engineering support that distributors cannot offer.
Manufacturer — Not a Trader
Every coupling manufactured in our Odhav, Ahmedabad facility. We control material selection, gear tooth profile, heat treatment, and surface finish.
Full Range In Stock
Standard sizes stocked in full and half gear configurations. Larger sizes and special materials are quoted per order. No minimum order for standard sizes.
Custom Bore — 3 to 5 Days
Bore machining, keyway cutting, and grub screw holes done in-house on CNC lathes. Any bore within rated range; tolerance to H7 or as specified.
Engineering Selection Support
Torque, service factor, and misalignment calculations provided free. Email a drawing or spec sheet to smigvs@gmail.com.
Competitive Ex-Factory Pricing
Gujarat manufacturer pricing — no trader margin. Volume pricing for monthly procurement partners. GST invoice from Ahmedabad.
Pan-India Dispatch Within 48h
Standard sizes ship same/next day via freight networks to Maharashtra, Rajasthan, Delhi NCR, Tamil Nadu, and all industrial states.
Lubrication & Maintenance
Lubrication is the only regular maintenance task a flexible gear coupling requires. Following the schedule below maximises gear tooth life.
Grease Selection
- Standard: EP2 lithium-complex grease, NLGI Grade 2
- High-temp (>60°C): synthetic EP grease rated for operating temp
- High-speed (>2,000 rpm): low-centrifugal-separation grease
- Do not mix grease types — purge and refill if changing brand
Re-greasing Schedule
- Normal (≤50°C, ≤1,500 rpm): every 2,000–3,000 hours or 6 months
- Demanding (>1,500 rpm or >50°C): every 1,000 hours or 3 months
- Fill quantity: 30–50% of sleeve cavity volume
- Full re-pack (clean + refill): every 15,000 hours
Inspection Checklist
- Monthly: check for grease leakage at seal faces
- Quarterly: check vibration level at coupling housing
- Annually: verify alignment with dial gauge
- On disassembly: inspect teeth for pitting, spalling, micro-cracks
Related Products & Guides
Explore SMI's full range of coupling types, manufacturer pages, and technical resources.
Product Pages
Star Coupling
Jaw-type coupling with star-shaped elastomer insert
RB Type Coupling
Rubber bushes in compression — shock absorption
Brake Drum Geared Coupling
Integrated CI brake drum for EOT cranes & hoists
Nylon Gear Coupling
Lubrication-free, lightweight — pumps & motors
Manufacturer Pages
Full Gear Coupling Manufacturer
Both-hub flexible — rolling mills, mining
Half Gear Coupling Manufacturer
One flexible + one rigid — pumps, fans
Brake Drum Coupling Manufacturer
CI drum couplings for cranes and hoists
Guides & Resources
Flexible vs Rigid Coupling
Misalignment, torque, cost comparison
Gear Coupling Selection Guide
Torque calculation, service factor, bore sizing
Installation & Alignment Checklist
Hub fitting, alignment targets, hub gap by FG size
All Products Catalogue
Browse all 31 coupling types from SMI
Get in Touch
Need a Quote or Technical Spec?
Our Ahmedabad factory team responds within 4 business hours. Fill our enquiry form or chat on WhatsApp for the fastest response.
Chat on WhatsApp+91 63510 70577Frequently Asked Questions
Common questions from engineers and procurement teams about flexible gear coupling selection, maintenance, and supply.
More questions about this page
What is a flexible gear coupling and how does it work?
A flexible gear coupling transmits torque between two shafts using meshing crowned gear teeth between an inner hub and an outer sleeve. The crown profile allows the hub to rock inside the sleeve as misalignment occurs, maintaining continuous torque transmission. Grease inside the sleeve lubricates the gear mesh and must be replenished at regular intervals.
What is the difference between a full gear coupling and a half gear coupling?
In a full gear coupling, both hubs have crowned gear teeth — both ends are flexible. In a half gear coupling, only one hub has gear teeth; the other end is a rigid flanged hub bolted directly to the mating flange. Full gear couplings suit drives where both shaft ends must accommodate misalignment. Half gear couplings are used when one end is already rigidly aligned.
What size flexible gear coupling do I need?
Start with the motor rated torque in Kg.M or Nm. Multiply by the service factor for your application (1.25 for conveyors, up to 2.5 for heavy shock drives). The result is your design torque. Select the FG size whose rated torque equals or exceeds your design torque. Call SMI at +91 63510 70577 — our engineers confirm the correct size at no charge.
How long do flexible gear couplings last?
With correct sizing, proper installation alignment (angular misalignment within ±0.5° at assembly, parallel within 0.25 mm), and regular greasing every 2,000–3,000 hours, flexible gear couplings typically last 20,000–40,000 operating hours. The most common causes of early failure are under-sizing, incorrect bore fit, missed lubrication, and misalignment exceeding rated tolerance.
Do you supply non-standard bore sizes?
Yes. SMI machines non-standard bore diameters and keyway widths within the rated bore range for each FG size. Custom modifications are typically completed within 3–5 working days from our Odhav, Ahmedabad factory. Provide your shaft diameter, keyway dimension, and required tolerance class when ordering.
What grease should I use in a flexible gear coupling?
Use EP2 lithium-complex grease (NLGI Grade 2) for standard conditions up to 50°C and 1,500 rpm. For higher speeds or temperatures, use synthetic EP gear coupling grease rated for your operating temperature. Fill the sleeve cavity to 30–50% volume — overfilling causes seal leakage and grease churning. Re-grease every 2,000–3,000 hours under normal conditions.
Super Mech Industries — Odhav, Ahmedabad, Gujarat 382415, India. Phone: +91 63510 70577. Email: smigvs@gmail.com. ISO 9001:2015 certified.