Midstream

Pump Station Pressure Control Pressure control of incoming and discharge flows at the pump stations directly correlates to overall pipeline safety and security. A critical part of the control systems is pressure control in the pipeline. Pressure control serves two essential purposes. The first is to control the discharge pressure of the pump station to achieve the proper flow rate and to attenuate pressure fluctuations in the transmission to downstream pump stations. The pressure control systems, which include valves and actuators, must ensure the pipeline is operating below the system design pressure. The second purpose of the pressure control system is to ensure that the incoming pressure to the pump station is kept above the NPSH (Net Positive Suction Head) required by the pumps in order to prevent cavitation within the pumps and the possibility of damage that could result from the cavitation. Pressure control is interactive from one pump station to another, which means that pressure fluctuations at one station will affect all of the other pump stations along the pipeline. The control system must be able to provide fast response to pressure disturbances during starts, stops, and flow rate changes. It must also provide fast response to set point adjustments at one station in order to achieve the desired flow rate and pressure at another Literature Download the Pump Station Pressure Control Application Spotlight! Download

Terminal Inlet Pressure Control Background Pressure control is critical when transferring crude oil and petroleum products from the main line to the terminal. Therefore, reducing the variation in delivery pressure will result in uniform flow rates that provide protection from over-pressure conditions in terminal systems. Installing a terminal inlet pressure control valve in the delivery line reduces pressure variation. The inlet pressure control valve is also known as a “holding pressure” or “delivery pressure” control valve. Achieving Poor valve performance could potentially cause unwanted pressure excursions – leading to unscheduled pipeline shutdowns and unit downtime. Problem High pressure differentials are concerning due to the potential cavitation in the flow through the terminal inlet pressure control valve. Cavitation will occur when the flow stream pressure falls below the fluid’s vapor pressure, therefore forming bubbles which will implode once the fluid pressure recovers. These bubble implosions cause severe damage to the valve and, consequently, to the downstream pipeline itself. Solution REXA Electraulic™ Actuators are the solution for fast response to signal command and precise modulation of the terminal inlet pressure control valve. This ensures proper flow control and stable pressure for safe operation. Literature Download the Terminal Inlet Pressure Control Application Spotlight! Download

Pump Recycle Control What is Pump Recycle Control? Pump Recycle Control, also known as pump re-circulation flow control, is one of the most common applications found within the Liquid Pipeline industry. Pump Recycle Control keeps pumps operating at a point on their curve. This preventative measure prevents over-pressure of downstream piping and components. The loop directly controls pressure and (by the nature of the system hydraulics) flow rate.  When selecting control valves for this application, it’s important to understand cavitation and consider designs that will limit it. Globe valve designs are generally preferred for pump recycle control due to their higher cavitation coefficient. Response times should be moderately fast.  Explore the significance of Pump Recycle Control, a crucial application in the Liquid Pipeline industry. Learn how it maintains optimal pump operation, prevents over-pressure, and the importance of selecting appropriate control valves to mitigate cavitation effectively. Literature Download to read the full Pump Recycle Control Spotlight! Download