IBL Testing

KW Designed Solutions has developed and engineered Pressure Vessel Systems specifically for carrying out Instrumented Buoyancy Loss (IBL) testing of subsea syntactic foam buoyancy products in line with API 17L (ISO 13628-11).

The IBL Pressure Testing System consists of a Pressure Vessel incorporating a Test Fixture to support the sample under test, a Pressure-balanced Load Cell, Pressure Transducer and a Pressure Control System complete with HMI control panel with an integrated PC based operator interface for data logging.

During a typical IBL test, the sample is subjected to hyperbaric pressure equivalent to the rated depth of the Buoyancy Module for over 96hrs.  The amount of buoyancy (or uplift) is monitored throughout the duration of the test and the amount of buoyancy loss is plotted and extrapolated out to end of life (EOL).

The Test Fixture that supports the sample is attached to the underside of the Vessel Cover - whilst lowering the sample into the Vessel, the Test Fixture supports the dry weight of the sample and ballast plates without overloading the precision load cell.  Once loaded and the Vessel filled with water, the locking mechanism is released so that the load cell is under tension for the duration of the test.

Data acquisition via a PC based operator interface allows the operator to write test programs, monitor and log pressure and force vs time as well as the log the temperature of the test media.  The user interface can be tailored to suit the customer requirements ensuring that the required outputs are achieved all via one system.

IBL Testing


  • Suitable for all sizes of Buoyancy Modules up to Ø1.6m x 3m
  • Protective framework with load rated lifting eyes
  • Removable Ballast System for neutral or negative buoyancy
  • Pressure balance load cell with low range, full scale resolution
  • Dry weight Load Cell protection mechanism
  • Fully integrated operator interface with pressure, temperature and force data acquisition


  • Specifically designed data acquisition to structure and simplify test operation
  • Low range, full scale resolution, pressure balanced load cell for increased accuracy – replaces the previous LVDT method of measurement
  • IBL Testing System can be supplied independently or as part of a turnkey package with a Pressure Vessel

Applications and Customer Uses

Specifically for use in Pressure Vessels for customers manufacturing and testing subsea syntactic foam buoyancy products in line with API 17L such as: Distributed Buoyancy Modules (DBM’s), Drilling Riser Buoyancy, ROV & AUV Buoyancy.

Project Examples

Project examples to follow

kw designed solutions

Tel: +44 (0) 1257 474 507

KW Designed Solutions Ltd, KW Group, Drumhead Road, Chorley North Business Park, Chorley, Lancashire PR6 7DE. United Kingdom.

Designed and manufactured in the UK Designed and manufactured in the UK.