2024 June

Emergency Removal of a Main Steam Line Plug: A Case Study

Preferred Engineering has decades of experience with the Main Steam Line Plug, and sometimes unique situations arise that make our our expertise in installation and removal especially important. A recent project required us to employ an MSLP Emergency Removal tool during the installation process. One of the latch mechanisms on the plug jammed during the plug installation, and […]

Fuel/Air Cross-Limiting

What is the Application? Steam supply and heating loads in a boiler plant vary throughout the course of the boiler firing cycle. In response to this, the boiler firing rate output % is continuously adjusting to maintain steam or temperature setpoint. This means that the boiler controller’s outputs (typically a fuel valve positioner, air damper positioner, and variable […]

Drum Level Control Essentials

What is the Application? As boilers convert water into steam to supply the plant’s load demand, more water must be supplied to the boiler to maintain the drum level at setpoint. In a modulating PID system, Boiler feedwater flow is controlled by the drum level controller by modulating a feedwater control valve which can be opened to give […]

Learning from Preferred’s Main Steam Line Plug Operating Experience

Preferred Engineering has extensive experience with the installation and removal of Main Steam Line Plugs. Over the years, we’ve developed a number of best practices that are key to maximizing efficiency and cutting critical path time. Here are some of the most important procedures we’ve established in recent MSLP projects: Camera Positioning Camera placement is one of the […]