tailieunhanh - CONTROL VALVE HANDBOOK Episode 2 Part 2

Tham khảo tài liệu 'control valve handbook episode 2 part 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Chapter 8 Installation and Maintenance Control valve efficiency directly affects process plant profits. The role a control valve plays in optimizing processes is often overlooked. Many process plant managers focus most resources on distributed control systems and their potential for improving production efficiency. However it is the final control element typically a control valve that actually creates the change in process variable. If the valve is not working properly no amount of sophisticated electronics at the front end will correct problems at the valve. As many studies have shown control valves are often neglected to the point that they become the weak link in the process control scheme. Control valves must operate properly no matter how sophisticated the automation system or how accurate the instrumentation. Without proper valve operation you cannot achieve high yields quality products maximum profits and energy conservation. Optimizing control valve efficiency depends on 1. Correct control valve selection for the application 2. Proper storage and protection 3. Proper installation techniques and 4. An effective predictive maintenance program. Control valve selection is covered in Chapter 5. The other three topics are included in this chapter. Proper Storage and Protection Proper storage and protection should be considered early in the selection process before the valve is shipped. Typically manufacturers have packag- 167 Chapter 8. Installation and Maintenance ing standards that are dependent upon the destination and intended length of storage before installation. Because most valves arrive on site some time before installation many problems can be averted by making sure the details of the installation schedule are known and discussed with the manufacturer at the time of valve selection. In addition special precautions should be taken upon receipt of the valve at the final destination. For example the valve must be stored in a clean dry place away from any .