罗斯蒙特 2051 无线直连式压力变送器技术说明.pdf

Technical Note Rosemount Pressure Transmitters 00840-0200-6114, Rev AA April 2019 Thread Galling Maintenance and Prevention Best Practices for Inline Pressure Transmitters and Manifolds 1.0 Overview Galling is a mechanical issue that can occur when metallic materials slide across each other. This is especially common in threads and can range from surface scratches to full thread deformation. Important threads to maintain are the process connection threads on inline pressure transmitters. Damage to these threads may cause delayed maintenance schedules, process readiness concerns, or transmitter replacement costs. Emerson uses industry standard NPT thread specifications for inline pressure transmitters and considers thread maintenance and integrity during factory assembly and shipping. Further recommendations for maintenance of the threads to ensure safe, consistent, and reliable process connections are outlined below. 2.0 NPT thread care Emerson ensures consistent thread quality through a variety of controls including raw material selection, thread creation techniques, transmitter assembly, and final quality tests. As galling occurs in metal to metal connections (e.g. NPT connections), thread care extends beyond the factory. The following steps can be taken to help maintain current and future thread integrity. 2.1 Lubrication If assembled at the factory, Emerson applies thread lubricants to avoid galling upon installation.