An automatic portable preassure testing RIG to determine the performance of the GRE composite pipes under various stress ratios
Abstract
This product is a novel automated pressure test rig to perform Ultimate Elastic Wall
Stress (UEWS) test. It is fabricated using Rotex make solenoid valves controlled using
NI DAQ and Labview interface. The test rig is designed to conduct pressure testing of
GRE pipes in accordance with ISO 14692 through ASTM D2992 document. The test rig
is capable of automatically testing under five stress ratios by a combination of internal
pressure and axial loadings through inclusion of indigenous design of pressure intensifier.
[pure axial (OH : 1A), hoop to axial (1H : 1A), pure hydrostatiC (2H : 1A), Quad hoop to
axial loading (4H : 1A) and pure hoop (1H : OA)l, The test rig also allows for short term
tests such as UEWS test where the strain response can measured and analyzed offline
to determine the initial failure of the pipe. The tubes are further tested until the weepage
failure occurs. The failure envelope for different stress ratios are mapped and provides a
design limits for engineers to design the composite pipes.
The results are associated with ASTM D2992 type of regression testing for the
determination of long term strength of composite pipes.