Weir completes sale of Flow Control unit to First Reserve

2019 ◽  
Vol 2019 (7) ◽  
pp. 14
Keyword(s):  
2015 ◽  
Author(s):  
S. V. Delia ◽  
M. V. Chertenkov ◽  
A. V. Zhakovschikov ◽  
V. V. Matsashik ◽  
O. N. Zhuravlev ◽  
...  

2010 ◽  
Vol 57 (4) ◽  
pp. 393-404
Author(s):  
Riza Gürbüz

Controlling Flow Rate and Fluid Level by Variable Frequency Drive Unit The Variable Frequency Drive (VFD) is used to control the speed of the pumpmotor to attain the desired flow rate and fluid level in a fluid system. An AC drive provides efficient flow control by varying the pump-motor speed. The comparison of energy requirements and costs in a system where a throttling device is used for flow control on a centrifugal pump with the power used when an variable frequency drive (VFD) is used to control the same flow, evidently shows potential savings. In this system, AC Motor Frequency drive and static pressure transmitter, turbine type flowmeter and Analog/Digital cards, micro-control unit and computer connection are designed specially to control flow rate, fluid flow type (turbulence or laminar) and water level at the different conditions with different PID parameters.


2015 ◽  
Author(s):  
S. V. Delia ◽  
M. V. Chertenkov ◽  
A. V. Zhakovschikov ◽  
V. V. Matsashik ◽  
O. N. Zhuravlev ◽  
...  

Author(s):  
Essam Elsaed ◽  
Mohamed Abdelaziz ◽  
Nabil A. Mahmoud

A unique method of improving energy efficiency in fluid power systems is called digital flow control. In this paper, binary coding control is utilized. Although this scheme is characterized by a small package size and low energy consumption, it is influenced by higher pressure peaks and larger transient uncertainty than are other coding schemes, e.g., Fibonacci coding and pulse number modulation, consequently resulting in poor tracking accuracy. This issue can be solved by introducing a delay in the signal opening/ closing of the previous or subsequent valve, thus providing sufficient time for state alteration and valve processes. In a metering-in velocity control circuit, a feedforward neural network controller was used to create artificial delays according to the pressure difference over the digital flow control unit (DFCU) valves. The delayed signal samples fed to the controller were acquired through the genetic algorithm method, and the analysis was performed with MATLAB software.


2020 ◽  
Vol 169 ◽  
pp. 150-157
Author(s):  
Alexander S. Lovtsov ◽  
Michael Y. Selivanov ◽  
Andrey N. Kostin

Author(s):  
N.S. Allen ◽  
R.D. Allen

Various methods of video-enhanced microscopy combine TV cameras with light microscopes creating images with improved resolution, contrast and visibility of fine detail, which can be recorded rapidly and relatively inexpensively. The AVEC (Allen Video-enhanced Contrast) method avoids polarizing rectifiers, since the microscope is operated at retardations of λ/9- λ/4, where no anomaly is seen in the Airy diffraction pattern. The iris diaphram is opened fully to match the numerical aperture of the condenser to that of the objective. Under these conditions, no image can be realized either by eye or photographically. Yet the image becomes visible using the Hamamatsu C-1000-01 binary camera, if the camera control unit is equipped with variable gain control and an offset knob (which sets a clamp voltage of a D.C. restoration circuit). The theoretical basis for these improvements has been described.


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