The inability to perform full strokes (FST) during the partial strokes (PST) has forced this research to be conducted. The essence of this project is to overcome the inability of the emergency stop system valve in the facility or platform to operate smoothly and successfully. This project will also emphasize on designing the logic controller using Ladder Logic Diagram on a Programmable Logic Controller (PLC).
Two (2) methods are implemented to successfully complete this project, requiring design and testing procedures. Both steps are implemented to obtain the data for analysis purposes in the final part of the project. I would like to take this opportunity to express my deepest gratitude to all parties involved in the implementation of this project, ranging from Universiti Teknologi PETRONAS teachers, technicians, graduate assistants to external institutions who have made great efforts to make this project a reality.
I am very grateful to my mentor, associate professor dr. To Nordin Saad, who guided me and gave me this once-in-a-lifetime opportunity to lead this project. I would like to dedicate this project to my family and friends who have given me tireless support and constant motivation to complete this project over the past year.
INTRODUCTION
- Background of Study
- Problem Statement
- Objectives and Scope of Study
- The relevancy of the project
- Feasibility of the project within the scope and time frame
The project aims to compare and verify the technology used for Partial Stroke Tests (PST) of ESD valves. The function of the logic software is very good, easy to understand and easy to use. The implementation of the logic is then performed on the installed valves to obtain the data and information required for analysis purposes.
The data is very important as it will determine the ability of the valves to perform as required by the customer, PETRONAS Group Technology Solution (GTS). The test is performed to verify the performance of the valves to operate in certain conditions for an extended period of time. Because of that, the Emergency Shutdown System (ESD) is very important as well as the last element of the system, the Valve.
This partial impact test of emergency stop valve is by performing testing the capacity and functionality of the particular valves due to the required requirements. Basically, the testing should be done in daily mode, by which one can identify the capability of the valves and analyze the problems faced during the testing process.
LITERATURE REVIEW
Critical Analysis of Literature
It shows that valve exercise is really important and necessary to avoid the problem from happening. However, if there is too much PST being tested, it will cause leakage at the valve. Disadvantage of leakage is not a good choice as it can disturb the operation of the valve afterwards.
Normally, the leakage always happened between the valves themselves and the body of the valve, because there is contact between them [5]. A ball valve is a valve that opens by turning a handle attached to a ball inside the valve. When the valve is closed, the hole is perpendicular to the ends of the valve and the flow is blocked by the ball.
Compared to ball valves, butterfly valves do not have pockets to hold fluid when the valve is in the closed position. Basically, it is the force required to move the valve from its initial position to start moving [9].
METHODOLOGY
- Procedure Identification
- Project Activities
- Tools and Equipment
- Software
- Hardware
- Project Design
The graph is also important as a collection of data for smoothness of valve movement during partial stroke testing. The objective of the analysis and data collection is to determine the advantages and disadvantages of both valves, ball and butterfly, for a particular vendor's product. For certain parameters, values were set before testing was performed, such as PST travel speed, drop rate, valve open percentage and much more.
The main criteria to consider is the ability of the valves to implement the PST and FST when both applications are required at certain times, especially the FST during an emergency shutdown. This criterion must be evaluated because, given the actual situation in the factory, we do not know the capabilities of the valves to perform the operation. This project has its specific procedures to implement the testing requirements for the PST and FST tests.
It is used and programmed to control the communication program within the PLC for the implementation of the PST and FST. The PLC inside the chassis will be the heart of the system which will execute the programming language to do the PST and FST testing. The Masoneilan ball valve is a valve that opens by turning a handle attached to a ball inside the valve.
For this Masoneilan ball valve, it is complemented by the pneumatic actuator that performs the movement of the valve by initiating the air pressure, controlled from the engineering workstation. Air pressure is applied to open and close the valve when the PST and FST tests are tested. Because the valve has two wings, the valve moves only a quarter of the cycle to perform the 100% opening [2].
The connection is basically from the layout of the drawing given by the supplier. The PLC is then connected to the multiplexer before connecting to the valves from different suppliers. The PLC contains programs that have been designed using ladders to implement PST and FST, while the multiplexer acts as the device to connect more than one instrument, and in this case they are ball and butterfly valves from each supplier.
RESULTS & DISCUSSION
Findings, Data Gathering & Analysis
The communication failure between the workstation and the valves is believed to be caused by the unstable functionality of the Hart communication means, MTL. In the middle of PST testing, the software suddenly indicates that the PST is not working. The graph also gives an accurate indication of the smoothness of the PST movement, showing valve position versus forced pressure.
Most of the time, the ball valve managed to complete the full stroke test (FST) on each test day. The ball valve managed to perform the "Triggered" operation when the signal is forced by tripping the system and not "turning off" the system. For PST, Droop is sometimes outside the limit, but since it is not affected by the PST test, it can be tolerated.
The graph also shows that the movement of the Butterfly valve is smooth without any problems during the PST test in the operating mode. The output pressure data is the pressure supplied by the regulator to initiate valve movement from its initial position. The drop data indicates the exhaustion of the air supply as the PST SVI II device is completing the PST test.
Due to the limitation of the set drop, the drop of the ball valve is always exceeded. Most of the time the indicator will show that the drop ball valve is in failure mode. However, the drop failure does not affect the PST testing as the PST testing is still successfully completed.
The importance of getting friction data is because it indicates the smoothness of the valve's movement. The result of the test of PST and FST is displayed after the test is completed. Compared to the Butterfly valve, the PST of the valve has a double failure for PST number 1 on day 24 and day 50 of the test.
But the rest of the PST test on the same day and on that period is tested successfully. The inability to perform the operation can be seen from the movement of the valve itself.
CONCLUSION AND RECOMMENDATION
Conclusion
Recommendation
9] Masoneilan SV II Quick Start Guide and Safety Manual ESD Smart Valve Interface with SIL 3 Emergency Shutdown.
