Non-Intrusive Multi-Turn Actuators - MXa | Limitorque - Flowserve MX is available for modulating applications up to 1200 starts per hour. Network Service MX is available for network applications that utilize Modbus, Foundation Fieldbus, Profibus DP or PA, DeviceNet, and HART. Linear Control Valve Service MX is available for use with control valves that may require exacting position utilizing a linear thrust base. Non-Intrusive Quarter-Turn Actuators - QX | Limitorque - Flowserve The Flowserve Limitorque QX, non-intrusive electric actuator is designed for a wide range of environmental applications in power, oil & gas, and water industries. The QX design builds on more than 20 years of proven MX technology to provide all the user-preferred features in a quarter-turn smart actuator package.