Ball Valve Flow Directions - Tee Port versus LPORT

L Port Valve and Tee Port (TPort) Valves are both known as 3-way valves due to their T-shape body with three ports. Both divert flow to and from different ports, however the L Port Valve has an elbow (L) shaped cavity a allows for through flow through only 2 x ports at the same time whereas the T Port Valve can facilitate flow through all ports if so required .

The L Port valve is commonly used to direct the flow from two separate sources in one direction. For example – When emptying tanks, once one tank is empty the fluid can be drawn from the next tank to the same line by turning the handle to change the source.

The T Port Valve is commonly used for directing the flow in two directions. Fluid is directed to more than one location simultaneously, passing directly through the valve body as well as to the side port at a slightly lower pressure.

See the diagram in the first photo here showing the various positions which can be selected for both the Lport and the Tport ball valve.

– Many actuators are 90 degree turn and only provide for any 2 of these available positions.

The actuator can only move sequentially through these positions. I.e. if one position as the starter position, the actuator can only turn the valve either one step forward or one step back in the diagram shown.
Eg for Tee port Position 1 can only turn to Position 2 or Position 4 (not to Position 3)