Model 626

Flow Switch, Inline Body, Seawater Deluge Service

The Delta Controls Model 626 Paddle Actuated Flow Switch is equipped with a body that becomes an unobstructed part of the pipeline. Model 626 is used to detect very low-flow rates in offshore deluge firewater piping systems. The Model 626 is equipped with a ‘fitted’ full swing-type paddle that fills the inside area of the in-line pipeline body under no flow conditions. It rotates 90 degrees to rest against the inside of the pipeline when the flow rate exceeds the calibrated alarm activation flow rate. The paddle has been ‘cupped’ and ‘fitted’ to fill the pipe and is flush against the pipeline’s interior curve during higher flow rates. Only the paddle’s thin edge, plus its support block, is in the flow resulting in a full pipe size open bore. Therefore during extremely high flow velocities no damage or pressure loss occurs.

For more than 15 years, the 626 has been used to detect seawater flow in deluge fire systems. It is also in service on drill ships and floating production facilities. Model 626 actuates at the very low-low rate which occurs when a single nozzle begins to operate. The paddle is magnetically connected to the output switch. A heavy-duty sealing tube separates seawater from the switch mechanism which eliminates failures occurring due to seal, diaphragm, and bellows leaks.