TTI Testing has a range of options available for Bend Fatigue and Cycling Bend over Sheave (CBoS) testing whether its for synthetic or wire ropes or electrical and umbilical cables including continuity monitoring.
Simple bend tests over a fixed bend/sheave to the more completed multiple driven sheave and reverse bend sets ups can be accommodated.
Most of our larger horizontal machines, utilising their modular fames can accommodate multiple sheave options and combined with our rotary motors give maximum flexibility.
Test bed lengths depending on machines can be up to 15 metres and can be combined with additional sub-assemblies to again provide further flexibility.
CBOS - Cyclic Bend of Sheave
Example of typical CBOS set up.
Dynamic Angled Bend Test
The video shows an example of a dynamic angled bend test with a synthetic rope being bent around a polymer liner. The fatigue test simulated the heave movements and imparted loads from a marine renewable energy device system. These tests were conducted as part of a MESAT supported programme. Details of the case study on this can be found here.
Key Bend Tests that can be offered:
Fixed bend test - such as OCIMF's MEG4 angled endurance test.
Dynamic angled bend test - Specimen is bent around a fixed bend/sheave but with varying wrap angle.
CBoS Test - Typical synthetic and wire bend test where tensioned samples are cycled around two sheaves using a long stoke resulting in single and double bend zones.
Reeling/Unreeling Test - Typically over a long-stoke to simulate deployment and retrieval off a winch or around sheaves etc.
Heave Test - Typically over a short-stoke to simulate vessel heave movements deployment and retrieval off a winch or around sheaves etc. An extended stroke length can be used where heave compensators are used.
Reserve Bend Tests - Typically combining multiple sheaves to bend specimens in opposing directions.
Driven or Locked Sheave - Used to assess dynamic and static friction coefficients.
Umbilical continuity can be checked continuously through tests.
Bend stiffness at temperatures.
FLIR and thermocouples for monitoring sample external and internal temperatures.