Water Weights® Proof Load Testing Bags

Water Weights® proof load testing bags are available in standard and specialist low-headroom configurations to accommodate different test loads and site conditions.

Standard Proof Load Bags (S Series)

Designed for general proof load testing, these raindrop-shaped bags provide a flexible water-filled testing solution for cranes, davits, beams and other lifting equipment.

Available models:

• BS 10S – 10 tonnes
• BS 20S – 20 tonnes
• BS 25S – 25 tonnes
• BS 35S – 35 tonnes
• BS 55S – 55 tonnes
• BS 110S – 110 tonnes

Low-Headroom Bags (L Series)

Designed for applications where lifting height is restricted, these bags feature a wider, shorter shape to accommodate test loads within reduced headroom.

Available models:

• BS 01L – 1 tonne
• BS 02L – 2 tonnes
• BS 03L – 3 tonnes
• BS 05L – 5 tonnes
• BS 065L – 6.5 tonnes
• BS 125L – 12.5 tonnes

Combined Load Configurations

Multiple bags can be combined using specially designed spreaders to achieve different test loads. The appropriate configuration depends on the required load, available headroom and rigging arrangements.

Building & Structural Load Testing

Water Weights® bags can be used for controlled structural load simulation during building construction. Water-filled bags allow loads to be applied and adjusted in stages, providing a flexible alternative to traditional solid weights where site access and available headroom are restricted.

Unique Group demonstrated this application during the Montevideo Residence project in Belgium, using fourteen 12.5-tonne bags to simulate changing structural loads while engineers monitored the building’s response.

Unique Group offers Water Weights® proof load testing bags for a wide range of marine, industrial and engineering applications, supported by specialist engineering and rigging capabilities.

• Extensive Capacity Range: Standard proof load bags up to 110 tonnes, alongside smaller low-headroom configurations.
• Flexible Testing Solutions: Water-filled bags suitable for indoor, outdoor, onshore and offshore applications.
• Specialist Low-Headroom Designs: Wider, shorter bags for testing where available lifting height is restricted.
• Engineering & Rigging Support: Assistance with test arrangements and specialised spreader configurations for combined loads.
• International Network: Access to Water Weights® equipment through Unique Group’s regional operations and partner network.

Equipment selection and load testing arrangements can be tailored to the requirements of individual projects.

Water Weights® proof load testing bags are available for rental and purchase through Unique Group, offering flexible options for temporary load testing projects and ongoing equipment requirements.

Rental

• Suitable for short-term and project-specific proof load testing.
• Standard and low-headroom bag options, subject to availability.
• Equipment selection based on required test load and site conditions.

Purchase

• Suitable for organisations conducting regular load testing operations.
• Standard bags and specialist low-headroom configurations available.
• Multiple-bag arrangements can be considered for specific testing requirements.

Rental and purchase availability, bag configurations and associated engineering support depend on regional capabilities and project requirements.

Unique Group supports Water Weights® load testing requirements through its international network of regional offices and independent partners.

Water Weights® proof load testing bags are available for rental and purchase enquiries across the Middle East, Europe, Asia Pacific, India, Africa and the Americas.

Our buoyancy and ballast teams can assist with equipment selection, capacity requirements, specialist bag configurations and project-specific rigging considerations.

Equipment availability, delivery arrangements and regional technical support depend on the project location and requirements.