Introduction
The double-girder semi-enclosed hook block consists of hook, pulley set, pulley shaft, crossbeam, bearings, semi-enclosed housing and anti-fall device. The hook is forged from high-quality carbon steel or alloy steel, with high strength and good toughness after heat treatment; pulleys are made of cast iron or cast steel, with machined rope grooves, wear-resistant and durable; crossbeam adopts high-strength alloy steel, with strong load capacity. The semi-enclosed housing partially encloses moving parts such as pulleys and bearings, with observation and maintenance openings on the top and sides, which can effectively prevent most dust and foreign object intrusion, extending the service life of bearings and pulleys, while facilitating daily inspection of wire rope wear, pulley operation and bearing lubrication status, maintenance without housing disassembly, balancing protection and convenience. During operation, the wire rope passes through the pulley set, transmitting the lifting force to the hook through the reeving mechanism to achieve heavy object lifting; the double-girder hook block is connected to the trolley frame through the crossbeam, suitable for large-tonnage lifting equipment such as double-girder bridge cranes, double-girder gantry cranes and metallurgical cranes. The hook is equipped with an anti-fall pawl to prevent accidental unhooking of slings; pulleys are equipped with anti-rope-off baffles to prevent wire rope . The double-girder semi-enclosed hook block is widely used in double-girder lifting equipment in industries such as machining, metallurgy, mining, ports and power, serving as the core lifting device for large-tonnage heavy object lifting, especially suitable for occasions requiring frequent inspection and maintenance.
Application
Our Advantage
Adopts a semi-enclosed housing to partially enclose moving parts such as pulleys and bearings, which can effectively prevent most dust and foreign object intrusion, extending the service life of bearings and pulleys, while reserving observation and maintenance openings, facilitating daily inspection of wire rope wear, pulley operation and bearing lubrication status, maintenance without housing disassembly, balancing the protection of fully-enclosed type and the maintenance convenience of open type.
Specially designed for double-girder bridge/gantry cranes, the crossbeam is rigidly connected to the trolley frame with uniform force and strong load capacity; pulley set reeving ratio 2~10, can amplify lifting force by 2~10 times, adapting to 5t~200t large-tonnage heavy object lifting, far superior to single-girder hook blocks, serving as an ideal lifting device for double-girder large-tonnage lifting equipment.
The semi-enclosed housing has observation and maintenance openings on the top and sides, allowing direct observation of wire rope wear, pulley operation and bearing lubrication status without housing disassembly, daily inspection and maintenance are convenient and fast; bearing grease nipples are exposed for direct oil lubrication, greatly shortening maintenance time and reducing maintenance cost, especially suitable for high-frequency operation occasions requiring frequent inspection and maintenance.
The hook is integrally forged from high-quality carbon steel or alloy steel, normalized and tempered, with high tensile strength, good toughness and impact resistance; each hook undergoes magnetic particle inspection and load test, safety factor ≥4 times, tested via 1.25× rated load static test, ensuring safe heavy-load lifting; equipped with an anti-fall pawl to prevent accidental unhooking of slings, safety performance far superior to welded hooks.
Semi-enclosed structure has lower manufacturing cost than fully-enclosed type and better protection performance than open type, with high cost-effectiveness; key components such as pulleys, hooks and crossbeams are all made of high-strength materials, normal service life over 10 years; compatible with 5t~200t various tonnage double-girder cranes, widely used in industries such as machining, metallurgy, mining, ports and power, serving as the most commonly used hook block form for double-girder lifting equipment.
Specification
| Parameter | 5~10t | 16~32t | 50~100t | 160~200t |
| Rated Capacity | 5/10t | 16/20/32t | 50/80/100t | 160/200t |
| Number of Pulleys | 2 pcs | 4 pcs | 6~8 pcs | 8~10 pcs |
| Reeving Ratio | 2 | 4 | 6~8 | 8~10 |
| Wire Rope Dia. | Φ11~Φ14mm | Φ14~Φ18mm | Φ18~Φ24mm | Φ24~Φ32mm |
| Pulley Dia. | Φ250~Φ350mm | Φ350~Φ500mm | Φ500~Φ710mm | Φ710~Φ1000mm |
| Hook Type | Single hook | Single hook / Double hook | Double hook | Double hook |
| Enclosure Type | Semi-enclosed (side opening) | Semi-enclosed (top / side opening) | Semi-enclosed | Semi-enclosed |
| Safety Factor | ≥4 | ≥4 | ≥4 | ≥4 |
| Hook Material | 20# steel / 20CrMnTi | Same as left | Same as left | Same as left |
| Pulley Material | Cast iron / Cast steel | Cast steel | Cast steel | Cast steel |
| Crossbeam Material | 45# steel / 40Cr | Same as left | Same as left | Same as left |
| Anti fall Device | Anti-drop pawl + anti-drop rope baffle | Same as left | Same as left | Same as left |
| Weight | 0.15~0.4t | 0.4~1.2t | 1.2~3.5t | 3.5~7t |
| Applicable Crane | 5-20t double-girder crane | 20-50t double-girder crane | 50-100t double-girder crane | Over 100t double-girder / metallurgical crane |
