The structural design of chain hoists (chain hoists/electric hoists) is centered around "lightweight, high reliability, and easy operation", and achieves multi scenario adaptation through modular component combinations. The structural characteristics are systematically analyzed from five dimensions: core components, material technology, transmission logic, safety mechanism, and structural innovation

1. Integration of core components and functions

Crane chain system: Made of high-strength alloy steel (such as 20Mn2, 20CrMnTi) forged circular chain or welded chain, in accordance with GB/T 1243-2006 standard. The single chain breaking force can reach 4-8 times the rated load, and the surface is polished/galvanized to reduce friction and wear. The dual chain/multi chain design can disperse loads and improve the stability of large tonnage models (such as 200kN class).

Transmission device: Manual type adopts planetary gear set (efficiency ≥ 85%) or worm gear mechanism, and torque amplification is achieved through small diameter sprocket; The electric type is equipped with a three-phase asynchronous motor and a reducer (such as a helical gear reducer), which can achieve stepless speed regulation; Hydraulic type is driven by hydraulic cylinders and suitable for explosion-proof/no power scenarios.

Braking and self-locking system: The ratchet and friction plate brake are the core, and automatic locking is achieved through spring force to prevent heavy objects from falling; Some high-end models integrate electromagnetic brakes or hydraulic locks, supporting power-off self-locking and precise hovering.

Hook and connector: The hook is made of forged alloy steel (such as 35CrMo), strengthened by heat treatment, and surface magnetic particle inspection ensures no cracks; Equipped with safety tongue and anti detachment device to prevent detachment; The connecting ring/shackle adopts standard interfaces to adapt to different lifting devices.

2. Material and process characteristics

Lightweight design: The shell is made of aluminum alloy die-casting or high-strength steel plate stamping, reducing weight by 30% -50% compared to traditional cast iron structures while ensuring impact resistance; The chain adopts high carbon steel quenching and tempering process, with a hardness of HRC40-50, balancing strength and toughness.

Surface treatment: Key components (such as sprockets and gears) are treated with carburizing and quenching+grinding processes, with a surface hardness of HRC58-62 and a tooth surface roughness of Ra ≤ 1.6 μ m, reducing the friction coefficient; The surface of the shell is sprayed/electrophoretic treated, with a corrosion resistance level of C4 (ISO 12944), suitable for humid/corrosive environments.

Sealing and lubrication: The transmission components adopt double lip oil seals or labyrinth seals to prevent dust/moisture from entering; The lubrication system uses lithium based grease, which is resistant to high temperatures (-20 ℃~150 ℃) and reduces wear.

3. Transmission logic and efficiency optimization

Manual transmission chain: manually pull the bracelet → drive the sprocket → drive the planetary gear set → drive the lifting chain up and down. By using a gear tooth ratio (such as 1:8) to achieve torque amplification, the operating force only requires 1/8-1/10 of the weight of the heavy object.

Electric/hydraulic transmission: The motor/hydraulic cylinder drives the reducer → drives the sprocket → drives the lifting chain. By using variable frequency motor or proportional valve control, it can achieve stepless speed regulation of 0.5-10mm/min, meeting the requirements of precise positioning.

Efficiency optimization: Reduce meshing impact through gear shaping (such as tooth profile shaping); Replacing sliding bearings with rolling bearings reduces the friction coefficient by 50%; The chain is arranged in an "8" shape to reduce twisting.

4. Security mechanism and redundancy design

Multiple protection: Overload protection devices (such as mechanical overload limiters) automatically cut off power when overloaded by 10% -15%; The upper and lower limit switches prevent top/bottom collision; The emergency stop button achieves instantaneous power-off.

Redundant design: Key components such as brakes and hooks adopt a dual backup design; The chain adopts a "redundant breaking force" design (safety factor ≥ 4); The shell adopts a reinforced rib structure to enhance its impact resistance.

Visual monitoring: Some high-end models integrate load sensors and display screens to display real-time load weight; Equipped with sound and light alarm device, it will automatically sound an alarm in case of overload or malfunction.

5. Structural innovation and scene adaptation

Modular design: Standard components such as sprockets, gears, and brakes can be quickly replaced, reducing maintenance time by 50%; Support customized lifting equipment (such as balanced lifting beams, rotating hooks) to adapt to special shaped equipment.

Compact design: The overall size of the crane is reduced by 40% -60% compared to traditional cranes, and it can be suspended on I-beams, crane rails, or dedicated brackets to adapt to the limited space of the factory environment.

Intelligent upgrade: Some models integrate wireless remote control and IoT modules, supporting remote operation and status monitoring; Implementing fault diagnosis and maintenance reminders through an app to improve operational efficiency.

The main equipment produced by Hebei Makita: stage electric hoist, electric chian hoist, wire rope electric hoist，Hand chain hoist, lever hoist, pneumatic hoist and other lifting equipment