Overhead Crane Configuration for Gear Manufacturing
Gear manufacturing (forged blanks 50–2,000 kg/pc, turned gears DIN Class 6–8, tooth surface hardness HRC 58–62, gear hobbing/grinding machines 5–30 t/pc, carburizing furnaces 3–10 t/pc) involves heavy-load, high-precision processing. Recommended configuration: QD double-girder 5–20 t + LD single-girder 3–5 t + cross-type gear lifting spreader + lifting magnet. Kelude's gear industry solutions apply graded protection levels tailored to each process stage.
Gear manufacturing (spur, bevel, and worm gears) progresses through forging, rough turning, finish turning, gear hobbing, heat treatment, and grinding. Product value rises steadily at each stage — a forged blank is worth roughly 5% of the finished gear, rising to about 15% after rough turning, 30% after finish turning, 60% after heat treatment, and 100% after grinding. Handling protection should escalate accordingly to safeguard the increasing value.
Forging Stage — Blank Loading & Unloading (Protection Level)
Gear blanks (50–2,000 kg each, 100–2,000 mm OD) arrive with a forged scale surface that is naturally resistant to scuffs and impacts. Lifting frequency between forging, normalizing, and rough turning is high — typically one to two lifts per part per operation. Furnace loading and unloading (normalizing at 900–950°C) requires heat-resistant fork attachments. Efficiency takes priority at the blank stage.
Recommended model: QD double-girder bridge crane, 5–10 t with a 15–20 m span, fitted with an adjustable lifting magnet (500–5,000 kg lifting capacity to suit varying blank weights). Heat-resistant fork attachments (rated for 1,000°C) for furnace handling.
Price reference: QD double-girder 5 t / 16 m span — approximately $11,900–$22,200 per unit. Kelude's forging-stage package includes the lifting magnet and heat-resistant fork attachments.
Turning & Gear Cutting — In-Process Part Transfer (Protection Level)
After precision turning and gear hobbing, the gear teeth already have finished tooth surfaces (DIN 6–8 grade, hardness HRC 58–62), representing 30–60% of the finished product's value. Any tooth face damage (dents ≥0.1 mm deep) requires rework, with repair costs running 2–3 times the original machining cost. Gears are transferred between machines using dedicated handling trolleys.
Recommended model: LD single-girder electric crane, 3–5 t capacity / 12–18 m span, fitted with a nylon woven sling (80 mm wide) plus a cross-shaped specialized gear spreader (three-point adjustable lifting claws with rubber coating) and a polyurethane tooth face guard. A jib crane assists with loading and unloading at gear hobbing and gear grinding machines.
Price reference: LD single-girder crane, 3 t / 15 m span: approx. $4,500–$8,900 per unit. Kelude's gear machining package includes the cross-shaped spreader, tooth face guard, nylon sling, and handling trolley.
3. Heat Treatment — Furnace Loading & Quench Tank Transfer (Protection Rating)
Gear heat treatment (carburizing at 930°C + quenching at 850°C + tempering at 200°C) requires loading gears into trays (200–1,000 kg per tray) for furnace charging and quench tank immersion. The immersion speed must not exceed 5 seconds to prevent hardness inconsistency, and the spreader must feature automatic load detachment.
Recommended model: LD single-girder electric crane, 3–5 t, heat-resistant type (Class F insulation, rated for 150°C) covering the entire heat treatment line. Equipped with an automatic-release quenching spreader (Inconel springs rated to 800°C) and a C-type tray spreader.
Price reference: LD single-girder heat-resistant crane, 3 t: approx. $5,900–$11,900 per unit. Kelude's gear heat treatment package includes the automatic-release spreader and quench time controller.
Gear Industry Crane Configuration Guide (by Process Protection Rating)
| Process | Protection Rating (IP) | recommended model | tonnage | Criticalrequirements | reference price |
|---|---|---|---|---|---|
| Blank | QD+Lifting magnet | 5~10t | Efficiency First | 8~1510K | |
| Turning | LD+nylon sling | 3~5t | Anti-Collision | 3~610K | |
| Gear Machining | LD+Cross Lifting spreader+protective cover | 3~5t | DIN 6~8Grade Anti-Collision | 3~810K | |
| Heat treatment | LDTemperature Resistance+Automatic Load detachment | 3~5t | FGrade/Oil Inlet≤5s | 4~810K |
Kelude Gear Handling Service Advantages
Kelude Heavy Industry's gear handling solutions introduce a stage-based protection philosophy: protection levels are matched to the value of the workpiece at each stage of production — electromagnetic lifting magnets for raw blanks, nylon slings for turned parts, cross-beam spreaders with protective covers for gear teeth, and heat-resistant automatic load-release hooks for quenching.
Stage-Based Protection Concept
Efficiency comes first at the blank stage (lifting magnet), with progressively higher protection during finishing (nylon sling, cross-beam spreader, and tooth face guard), and heat-resistant automatic release during quenching.
Bull Gear Handling Solution
For bull gears over 1 m in outer diameter, we supply a cross-beam spreader with polyurethane-coated grippers, a tooth face guard, and a dedicated transfer trolley with V-shaped polyurethane cradles.
Gear Handling FAQ
Q: How do you safely move gears between machining centers?
A: For large gears (outer diameter >1 m, >500 kg): ① An overhead crane lifts the gear onto a dedicated gear transfer trolley (V-shaped polyurethane cradle with locking casters); ② the trolley is pushed manually to the next machine; ③ a cross-beam spreader lifts the gear off the cradle and positions it onto the machine chuck. Note: the cradle contact surface is polyurethane with Shore A60 hardness — never allow bare steel to contact the gear teeth. Kelude supplies the complete package: transfer trolley, cross-beam spreader, and tooth face guard.
Q: How does the automatic release spreader work for quenching?
A: The automatic release spreader works as follows: ① C-hook jaws are held closed by torsion springs; ② once the load tray is hooked and lowered into the quench oil tank, the tray touches the tank bottom and its dead weight overcomes the spring force, opening the jaws; ③ as the spreader is lifted, the jaws automatically reset. Release takes ≤2 seconds, ensuring the spreader never enters the oil. The heat-resistant springs are Inconel X750 (rated to 800°C) with an automatic reset mechanism. Kelude's quenching spreader has passed 100,000-cycle endurance testing with zero failures.
Q: How are the lifting points adjusted on the cross-beam gear spreader?
A: The cross-beam spreader (applicable to gears with outer diameters of 200~2,000 mm): ① the cross beam and main beam are connected through a central sliding sleeve, allowing radial adjustment along the gear (range 100~1,000 mm); ② four grippers clamp onto the gear ends (not the tooth faces) with polyurethane padding; ③ gripper positions are locked manually by gear outer diameter (star handle + lock nut); ④ spreader dead weight is 30~80 kg, with a load capacity of 500~3,000 kg. Kelude customizes the radial adjustment range of the cross-beam spreader to match your gear specifications.
Q: How many cranes does a gear workshop need?
A: For a standard gear workshop (annual output 10,000–50,000 pieces, outer diameter 100–2,000 mm), the recommended configuration is: ① blanking/rough turning area — one QD 10t crane (with lifting magnet); ② finishing/gear cutting area — one LD 5t crane (with cross-type lifting spreader and protective cover); ③ heat treatment area — one LD 3t heat-resistant crane (with automatic load detachment); ④ inspection/assembly area — two 250kg jib cranes. Total investment: approximately $22,000–$45,000. Kelude Heavy Industry calculates the optimal configuration based on product specifications and production capacity.
