Heavy Duty Manual Block | HSZ‑VD

HSZ‑VD Heavy Duty Manual Block - Upgraded Industrial Chain Hoist

The HSZ‑VD series represents the next generation of heavy-duty mechanical lifting, engineered specifically as a high-performance upgraded model from traditional HSZ systems. Operating entirely independent of electrical power grids, this premium heavy duty manual block delivers dependable, high-tonnage lifting capacity ranging from 0.25 tons to 50 tons, making it an essential utility for off-grid rigging projects, remote coastal operations, and severe industrial environments.

As an established global chain block supplier, LDR Rigging designs the HSZ-VD series to cross-align with stringent international safety benchmarks. By integrating premium alloy steel gear sets and structural reinforcements, this model reduces required manual hand-pull tension while guaranteeing zero-drift mechanical load holding under continuous duty cycles.

Technical Features & Mechanical Configurations

• Advanced Kinetic Gear Transmission: Internal gear assemblies are precision-machined from 20CrMnTi alloy steel and subjected to strict carburizing heat treatment, maximizing structural torque transfer while minimizing manual pulling force.

• Fail-Safe Weston Brake Architecture: Equipped with a synchronized double-pawl precision braking system that delivers instantaneous mechanical locking the millisecond the operator ceases hand chain movement.

• Integrated Chain Bottom Protection: Features an engineering-grade long shaft stop back washer that locks the sprocket and nut, preventing the load chain from bottoming out or causing mechanical brake failures.

• Anti-Jam Stamped Chain Guides: Outfitted with an optimized, heavy-gauge stamped chain guide plate that facilitates fluid chain movement and eliminates the risk of chain derailment or jamming under complex rigging angles.

• Reinforced Structural Housing: The outer hand chain cover incorporates a rolled-edge reinforcement layout, delivering exceptional impact resistance to safeguard internal drive mechanics in harsh industrial environments.

• Calibrated European Standard Load Chain: Rigged with high-tensile, European standard Grade T8/G80 lifting chain fully compliant with EN818-7 certification requirements.

Technical Specifications

The metrics outlined below represent the engineering standards for our main commercial chain block hoist product line. For custom technical drawings, alternative material coatings, or volume freight packaging, please contact our export logistics team.

Capacity(t)	0.25	0.5	1	1.5	2	3	3	5	10	20	30	50
STANDARD LIFT(m)	2.5	2.5	2.5	2.5	3	3	3	3	3	3	3	3
Running test load(KN)	3.1	6.3	12.5	18.8	25	37.5	37.5	62.5	125	250	375	625
Effort required to lift rated load（N）	190	262	265	265	272	320	280	358	370	370*2	370*2	370*2
Strands of load chain	1	1	1	1	1	1	2	2	4	8	12	22
Dia. of load chain	4	6	6	7.1	8	10	7.1	10	10	10	10	10
Dimensions (A) (mm)	104	126.5	143	148	152	181	156	181	181	192	330	410
Dimensions (B) (mm)	100	136	156	182	198	266	214	266	365	630	670	900
Dimensions (C) (mm)	230	266	324	392	407	636	465	636	798	890	1000	1950
Dimensions (D) (mm)	30	36	40	52	52	60	60	68	85	106	106	170
Dimensions (K) (mm)	23	25.5	28	38	38	40	42	50	57	84	84	130
Net Weight(kg)	4.2	9.2	11.3	15.6	19	28	23.4	43.2	76.8	160	230	1085
Extra weight per metre of extra lift (kg)	1	1.7	1.7	2	2.3	3.1	3.1	5.3	9.8	19.6	28.3	50
Package size	17*15*14	20*16*19	23*18*20	29*22*22	29*22*22	40*25*24	33*25*21	42*28*24	54*49*30	80*72*34	88*78*40	160*130*90

Heavy-Duty Industrial & Marine Applications

The HSZ-VD heavy duty manual block is specifically engineered to deliver reliable mechanical advantage in high-consequence lifting environments. By operating independently of the electrical grid, it serves as a critical asset across a diverse spectrum of heavy industries:

Infrastructure & Construction Sites

• Structural Steel Erection: Provides precision micro-positioning during the alignment and bolting of heavy structural steel I-beams and overhead trusses.

• Precast Concrete Handling: Enables safe, gradual vertical positioning of heavy precast concrete wall panels, bridge segments, and formwork assemblies where sudden drops could cause structural failure.

• Off-Grid Utility Rigging: Serves as the primary lifting mechanism on bridge decks, high-rise frameworks, and remote civils projects before temporary site power is established.

Heavy Manufacturing & Production Plants

• Tooling & Die Management: Streamlines the removal, flipping, and installation of multi-ton injection molds, stamping dies, and heavy casting patterns within restricted press beds.

• Assembly Line Servicing: Safely positions massive industrial gearboxes, electric motor blocks, and heavy hydraulic cylinders during the integration and overhaul of plant machinery.

• Intralogistics Upgrades: Acts as a dependable backup or auxiliary hoist for handling irregular, high-tonnage materials outside the coverage grid of existing overhead traveling cranes.

Shipbuilding, Repair, & Marine Operations

• Hull Plate Alignment: Delivers continuous high-tension pulling force required to pull massive curved steel hull sections into precise alignment for automatic welding.

• Engine Room Outfitting: Fits seamlessly into tight, low-headroom spaces below deck to lower heavy marine diesel crankshafts, auxiliary generators, and heavy valve blocks.

• Corrosive Port Rigging: Features a rolled-edge reinforced shell and high-tensile coated chain options to withstand the severe salt-spray, high-humidity, and washdown protocols of active shipyards and dockside maintenance.

Industrial Warehouses & Logistics Hubs

• Freight De-Stuffing: Manages the offloading and positioning of unpalletized, oversized industrial machinery, steel coils, and crated goods from flatbeds and shipping containers.

• Racking Infrastructure Setup: Facilitates the safe suspension and anchoring of structural cantilever racks, overhead conveyor tracks, and heavy automated storage equipment.

Subterranean & Open-Cast Mining

• Intrinsic Spark-Free Safety: Operates as a completely manual mechanical hoist, eliminating electrical arcing risks in volatile, high-dust, or explosive gassy environments typical of underground coal and hard-rock mines.

• Conveyor & Track Maintenance: Assists field technicians in tensioning heavy conveyor belts, replacing heavy drive sprockets, and laying structural rail track inside restricted mine shafts.

• Mobile Drilling Rig Support: Provides portable rigging support for lifting drill strings, pump segments, and heavy extraction components in rugged, unpowered terrain.

Equipment Installation, Maintenance & Turnarounds

• Petrochemical Plant Shutdowns: Used extensively during planned facility turnaround schedules to safely lower heavy heat exchanger tube bundles, blind flanges, and high-pressure process valves.

• HVAC Overhead Rigging: Allows commercial mechanical contractors to hoist massive rooftop air handling units, industrial chillers, and heavy cooling towers onto structural vibration pads.

HSZ Series Hoist Core Components & Engineering Specifications

1. Load sprocket with bearing

• Precision-Machined Kinetic Hub: Heavy-duty load sprocket integrated with premium, smooth-running needle roller bearings.

• Friction Core Minimization: Drastically reduces drive friction under peak loads, eliminating localized wear and delivering seamless chain pocket alignment under intensive rigging cycles.

2. Long shaft gears

• High-Torque Power Transmission: Drop-forged and precision-machined steel long shaft gears engineered for high torsional fatigue resistance.

• Carburized Hardness Matrix: Features specialized heat treatment to optimize tooth surface alignment, ensuring wear-free kinetic engagement during heavy, non-stop industrial lifting.

3. End anchor with pin

• Fail-Safe Chain Termination: Rigid, heavy-gauge steel end anchor secured via an industrial safety positioning pin system.

• Anti-Dislodgement Framework: Eliminates structural failure and link slippage risks at the dead end of the load chain under maximum operational stress.

4. Gear cover with bearing

• Reinforced Structural Chassis: Industrial gear cover integrated with a heavy-duty alignment bearing assembly.

• Anti-Deformation Defense: Provides rigid, precise internal support for the gear axles, preventing housing distortion and tracking misalignment under offset or continuous lifting angles.

5. Chain guide plate

• Anti-Jam Calibration Device: Stamped heavy-gauge chain guide plate engineered to maintain continuous parallel alignment of the load chain.

• Flawless Tracking System: Prevents link twisting, pocket derailment, or catastrophic chain snapping by smoothing out rapid vertical line flows.

6. Integral bearing

• Heavy-Duty Friction Reduction: Premium, fully integrated sealed bearing engineered to replace traditional low-efficiency bronze friction bushings.

• Extended Fleet Lifecycle: Lowers required operator hand-pull tension while protecting the internal shaft assemblies from long-term fatigue under dusty, high-vibration site conditions.

7. Hand chain wheels with anti-stop washer

• Kinetic Security Architecture: Precision-balanced hand chain sprocket equipped with a specialized mechanical locking anti-stop washer.

• Anti-Backslip Defense: Prevents component loosening and locking nut vibration displacement, ensuring the Weston braking core remains perfectly synchronized with hand inputs.

8. Unique curled edge

• Impact-Resistant Geometry: Heavy-duty outer wheel housing featuring a reinforced rolled/curled edge structural modification design.

• Severe-Environment Armor: Delivers immense structural rigidity to withstand crushing impact shocks, while guiding the hand chain smoothly without any risk of edge snagging or jamming.

EU CERTIFIED EN818-7 STANDARD PATENT LIFTING CHAIN	ALLOY STEEL HOOK	DOUBLE POSITIONING PIN END ANCHOR
SPECIALLY DESIGNED FOR LIFTING AND EASY LIFTING	DOUBLE PAWL PRECISE BRAKE	LIGHT HAND PULL

Certifications & Quality Assurance

• ✅ EN818-7 European Standard
• ✅ CE Certified
• ✅ ISO 9001 Factory
• ✅ OSHA Compliant
• ✅ Factory Test Reports Available
• ✅ Third-Party Inspection Supported (SGS, BV, ABS)

Related Products

• HSZ-G Hand Chain Hoist - Standard model
• HSH-V Lever Hoist - Alternative manual hoist
• Electric Chain Hoists - Powered option
• Grade 80 Lifting Chains - Replacement chains

B2B Compliance & Transactional Framework

Regulatory Certifications

• Fully compliant with EN818-7 European Lifting Standards and CE Directives.

• Manufactured under strict ISO 9001 Quality Management System controls.

• Aligned with OSHA Safety Mandates for heavy industrial rigging machinery.

• Complete factory proof-load test certificates available; fully supports independent third-party verification inspections (SGS, BV, ABS).

Customization & Global Procurement Terms

• Lift Height Modification: Standard 2.5m - 3m vertical ranges can be custom-engineered in calibrated 1-meter increments to fulfill complex project blueprints.

• Spare Parts Lifecycle Assurance: Original, fully traceable factory components—including certified load chains, drop-forged alloy hooks, friction discs, precision bearings, and guide plates—are maintained in continuous stock for rapid maintenance deployment.

• Enterprise Financial Options: We accommodate professional international trade transaction structures, including Telegraphic Transfer (T/T) (30% deposit / 70% balance pre-dispatch) and Irrevocable Letters of Credit (L/C at sight) for contract or wholesale purchase volumes.