Which types of valves are permissible to use in NH3 systems?

In ammonia (NH3) systems, the use of specific types of valves is critical due to the properties of ammonia as well as operational requirements. The correct answer identifies globe, angle, and quarter-turn valves with specific actuation as permissible options.

Globe valves are suitable for controlling flow and throttling, which is essential in ammonia systems to manage pressure and flow rates effectively. Angle valves, which are designed in a configuration allowing for better flow management in pipelines, help minimize pressure drops and are also resistant to the corrosive nature of ammonia.

Quarter-turn valves, such as ball valves, provide quick shut-off capabilities, which are vital in emergency situations where swift action is required to prevent leaks or pressure build-up. The mention of specific actuation highlights the importance of using the correct materials and mechanisms to ensure the safety and reliability of the valve operation under the demanding conditions present in ammonia systems.

Overall, the selection of these valve types, along with appropriate actuation, ensures that the system operates safely and efficiently while adhering to the necessary standards and regulations for handling ammonia.