Organize the content of the dashboard posts

Thread Content

This post was last edited by Wang Tianze on 2016-7-9 at 12:29. As of now, the number of topics in the dashboard is 51520; the purpose of this reward offer is to address the issues present in these posts on the dashboard. And summarize the issues. Examples: 1. Instrument failure categories: 1.1 Temperature instrument failures; 1.2 Pressure instrument failures; 1.3 Flow meter failures; 1.4 Level gauge failures; 1.5 Actuator failures; 1.6 Positioner failures. 2. Instrument selection-related issues. 3. Instrument calibration-related issues. How to participate: Submit your issue in this post (a brief description of the failure plus a link); do not submit the same link multiple times. Additionally, organize and summarize the content of the control-related posts. Please note that unresolved issues should not be submitted. Resource posts, please do not submit. Thank you. This is meaningless spamming behavior; please have the moderator handle it. Thank you! Examples are as follows: [Flow Meters – Throttling Elements] Sharp and obtuse surfaces of orifice plate flow meters. Address: http://bbs.hcbbs.com/thread-1600128-1-1.html Q: Why are there sharp and obtuse surfaces on an orifice plate flow meter, and what is their function? A: There is an issue related to the flow direction when installing an orifice plate flow meter. When installing the orifice plate, the sharp-angle end must face the direction of the flow of the medium, while the obtuse-angle end should face downstream; it must not be installed in reverse. This problem does not exist in two-way metering orifice plate flow meters. Q: Are there any considerations to prevent the formation of vortices? A: After the flow rate decreases, it needs to recover, and an acute angle will facilitate this recovery by reducing turbulence and thus pressure loss. A: Standard orifice plates have a directional property, so they cannot be installed in the wrong orientation. The acute angle is at the front, and the obtuse angle is at the back. The purpose is to increase the differential pressure and reduce the pressure loss due to eddies. reward_7ree