Proof Test





We’ve an unrivalled reputation for the quality and reliability of our proof testing solutions.

For over 30 years, we’ve manufactured and supplied water-filled proof test bags to organisations across the globe to test the strength and safety of lifting equipment and structures.

Our easily transported and stored proof test bags are used daily across the globe by partners in:

Marine and shipping construction
Oil and gas industry
Defence industries
Crane, winch and davit manufacturers
Lifeboat construction

“Our relationship with Structure-flex began in 1996. Their know how has proven to be reliable from the beginning.

In 2009, we worked together to create the first 100 tonne load testing waterbag in the world.

We are proud to have Structure-flex producing our high standard products for more than 20 years now.”

Eddy Schroemges, Director

Get in touch

Testing Bags

Our incredibly tough and versatile water-filled proof test bags are manufactured to the highest standards, in capacities up to 110 tonnes.

Proof Load Testing Bags

Our standard proof test bags are manufactured in sizes ranging from 1 to 110 tonnes.

In addition, we provide a range of low head room test bags for use in restricted height environments, from 1 to 15 tonnes.

Test bags are where possible TUV NEL dynamic type tested up to a 6:1 safety factor, with larger bags undergoing mechanical stress calculations completed by a professor of mathematics, or expert Finite Element Analysis modelling.

European manufactured 1680g/m2 PVC coated 2,200 dtex polyester 3×3 weave
Harness assemblies to BS EN1492-1:2000 with 7:1 safety factor
Genuine Green Pin shackles to BS EN13889 and FRAM quad links to BS EN1677-4
Manufactured using the latest high-frequency welding technology
Single lifting point for ease-of-use
Available in orange and yellow material, or as a hybrid combination

Standard Test Bag

Low Head Test Bag

Standard Test Bag Specifications

SIZE (tn)	CAPACITY (kg)	HEIGHT (m)	DIAMETER (m)
1	1,000	2.4	1.2
2	2,000	3.7	1.7
3	3,000	4.1	2.0
5	5,000	4.6	2.1
10	10,000	5.8	2.4
20	20,000	5.8	3.7
25	25,000	6.1	3.8
35	35,000	7.0	4.2
50	50,000	8.5	4.6
55	55,000	8.9	4.8
100	100,000	10.7	5.9
110	110,000	12.0	5.9

Low Head Test Bag Specifications

SIZE (tn)	CAPACITY (kg)	HEIGHT (m)	DIAMETER (m)
1	1,000	1.5	1.5
2	2,000	1.8	1.8
3	3,000	2.3	2.1
5	5,000	3.4	2.3
6.5	6,500	3.7	2.3
12.5	12,500	4.7	2.8
15	15,000	5.1	2.8

DOWNLOAD INFORMATION

Lifeboat Testing Bags

Our cylindrical lifeboat bags are used to provide a simple and accurate way to load test lifeboat supports and winches and other emergency craft in situ.

They provide a uniformly distributed load and are easy to use, transport and store.

Available in standard capacities from 100kg to 500kg, with bespoke designs available.

European manufactured 1680g/m2 PVC coated 2,200 dtex polyester 3×3 weave
1” BSP flanged brass fill/empty port
1” BSP ball valve with camlock fitting
Separate 2 PSI pressure relief valve
Handling straps for ease-of-positioning
Easy to fold and compact to store
Also available with manifold, pipework and air pump

Gangway Testing Bags

Our cylindrical gangway bags are used to provide a simple and accurate way to load test gangway, walkways and ladders.

They provide a uniformly distributed load and are easy to use, transport and store.

Available in standard capacities in 1,000kg to 1,500kg.

European manufactured 1680g/m2 PVC coated 2,200 dtex polyester 3×3 weave
2” BSP GRPP fill/empty port(s) for strength
2” BSP ball valve(s) with camlock fitting
Separate 2 PSI pressure relief valve
Handling straps for ease-of-positioning
Easy to fold and compact to store
Bespoke sizes available upon request

Lifeboat and Gangway Test Bag Specifications

Model No.	CAPACITY/SWL	DIAMETER (m/ft)	LENGTH (m/ft)
LBB100	100 KG	0.32m/1.05ft	1.24m/4.07ft
LBB200	200 KG	0.47m/1.54ft	1.16m/3.81ft
LBB250	250 KG	0.47m/1.54ft	1.45m/4.76ft
LBB350	350 KG	0.47m/1.54ft	2.00m/6.56ft
LBB375	375 KG	0.47m/1.54ft	2.17m/7.12ft
LBB500	500 KG	0.50m/1.64ft	2.60m/8.53ft
GWB1000	1000 KG	0.60m/1.97ft	3.55m/11.65ft
GWB1500	1500 KG	0.60m/1.97ft	5.33m/17.49ft

DOWNLOAD INFORMATION

Moon Pool Test Bags

Moon pools or ‘wet porches’ are used by drilling platforms, fishing vessels and exploration vessels which need to test the winch equipment, tasked with lowering expensive equipment such as diving bells in confined spaces.

Capacities have ranged from 400kg to 48 tonnes, utilising a cylindrical shaped design as opposed to the ‘teardrop’ shape seen with traditional crane test bags.

To offer enhanced strength and all-important dimensional stability when full, several 30cm wide circumferential polyester webbing bands are introduced to the design to ensure the bag does not ‘bulge’. This helps prevent side wall or other structural damage during testing.