| 摘要 |
A data acquisition system (1) by which environmental parameters proximate to plant installed valves (2) may be monitored, recorded and correlated with other valve operating data. The system includes sensors (8) for sensing environmental parameters such as gas/vapor concentration, temperature or humidity. The system also includes sensors for sensing changes in the actuating variable (34) and sensors for sensing valve stem displacement (58). The sensors (8, 34, 6) generate electrical signals proportional to the value of the sensed parameter. First data interface equipment (32, 42, 43) is provided for digitizing the sensed actuating variable as the actuating variable is changed to displace the stem, preferably a full stroke from the open-to-close-to-open positions or vice versa. Second data interface equipment (7, 45) is provided for digitizing the sensed environmental parameter as the stem is displaced. Third data interface equipment (6, 45) is provided for digitizing the sensed stem displacement. The digitized data are stored, preferably with a computer (45) and associated random access memory, and can later be uploaded for use in, for example, a plant database system or correlated to evaluate valve operability.
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