Siemens intelligent valve positioner and the selection and application of engineering practice case
1, selection of smart valve positioner
In the project Settings, select the appropriate intelligent valve positioner, have to pay attention to the following:
(1) required to satisfy the operating mode, implement intelligentized: we choose our intelligent valve positioner, is to obtain the function of the intelligent and improve overall control requirements. Therefore, under the condition of meet the condition, intelligent is our important indicator. Intelligence includes its communication function, online or offline fault diagnosis function, etc.
(2) require site operation more convenient: for some intelligent valve positioner products, due to the set is more complex, affect the product effect in actual use. So, we first convenient operation of the product.
High performance/price ratio, and (3) requirements, save energy consumption and cost, besides considering an investment instrument, we also think of running cost. Look from time, choose the products with high comprehensive ability.
(4) on site show that for some intelligent valve positioner products, because there is no LCD display, so must use hand operator to adjust them in the adjustment. This increases the cost.
(5) requirements in some cases, to ensure the normal work of the remote installation: because now large petrochemical enterprises adopt combination is more and more, so the distance from the control room to the field only valve locator may be far away, must consider the problem of voltage drop cable, smart valve positioner can not work normally.
2, the intelligent valve positioner application case in engineering practice
In the process of engineering construction and device driving operation, due to the design, construction and maintenance of a variety of reasons, the regulator can produce all kinds of faults. For some problems, can be solved through the intelligent valve positioner.
Case 1:
Refinery plant found in the operation process a few regulator can't open or not fully closed. Through inspection, after exclusion of all other factors, due to the actual operating pressure is higher than the design pressure, valve differential pressure of the friction force increases and actuator can't overcome. In this case, the change or more actuators, or to find a way to increase the air pressure. Due to the replacement actuators are time-consuming, affected the normal production plant is the most important, so try to increase the air pressure. Site USES is ordinary locator and filter pressure reducing valve, adjust the filter decompression outlet pressure, still can't solve the problem, the experiment instrument directly to membrane actuator head wind, problem solving. But as a result of public pressure fluctuations and other factors, the influence of ordinary locator can't normal use and regulation. Siemens intelligent valve positioner, therefore, is not being affected by the fluctuation of the gas source, the locator before installation on the filter after installation to the valve, regulating valve normal work, to solve problems.
Case 2:
Plant shutdown overhaul. Regulating valve testing a lot of work, time is tight, the task. Due to Siemens intelligent valve positioner valve configuration, fault diagnosis function, it has rich heroine with Siemens intelligent valve positioner fault diagnosis to the regulator, including valve leak amount, key parameters such as the valve packing according to the results of fault diagnosis for problematic regulator to be removed for maintenance, and there is no problem of the regulator is confirmed as can normal use. After construction, after a year of operation, prove that the regulator working in good condition.
Case 3:
A few years later, a factory, because the regulator was put into operation data of constant use and personnel changes, cause a loss of data. When new project and transform, chose Siemens intelligent valve positioner, through the corresponding hardware and software, the locator and the related information to ensure factory, in the later during the production and maintenance, easy to access and use.
Case 4:
Petrochemical plant regulator, as involves selecting the role, but in the construction process for reaction, which requires the regulator to adjust. Due to the regulator to adjust more troublesome, choose Siemens intelligent valve positioner, so, by simply adjusting the parameters of the intelligent valve positioner, the transition of the regulator is positive and negative effect problem.