Siraj Kapasi

Title: M.S.. candidate in Industrial Engineering Advisor:  Dr. David Hall Topic: Automated Liner Displacement Mapping during Liner Buckling Experiments

The aim of this research program is to study the radial deflections of liner as a function of the external pressure applied to the liner system. Another important factor that can be determined by measuring the radial deflections is how the pipe interacts with the host pipe. By studying how the liner deforms outward (outward deformation occurs opposite the lobes), it is possible to detect when the pipe contacts the host pipe. Understanding this interaction with the host pipe is important for obtaining a more complete picture of the evolution on conditions leading to liner buckling.     Thus, with this aim, an automated radial deflection system which will measure the deflection of the liner due to external water pressure was setup. This setup consists of an Linear Variable displacement transducer (LVDT), data acquisition system which connects the LVDT to the computer. A program is written in HP Visual Engineering Environment (HPVEE) controls the whole system through computer. Even before studying the above effects of pressure on liner, errors and variations involved in the automated system will be determined. The repeatability of the LVDT, radial and longitudinal variations in the lead screw and other sources of error will be identified and an effort will be made to quantify all the possible error. Different test to be performed to study deflection history: Perform the short-term test - Collect the radial deflection readings for one cycle at each increments of the pressure till the pipe buckles. This type test generally is over within 2-3 days. Perform long-term test – Collect the data at random intervals of time. Pressure is kept a constant setting. This type of test takes time depending upon the applied pressure, generally 2 – 12 weeks for pressures from 115 Psi. to 90 Psi. Higher the pressure, quicker the test ends.