When a LACT unit is in operation, the sampler (which typically consists of a small piece of pipe or tubing with a beveled end that is inserted horizontally through the LACT pipe wall) is connected to a small solenoid-operated valve which periodically opens for a short time to permit the line pressure to force a small amount of fluid through the tubing and solenoid valve into the sample regulator.   The line pressure compresses the regulator’s diaphragm load assembly to the precisely calibrated volume of crude oil, i.e., 8 cc’s.  As soon as the sampler solenoid is de-energized, the trapped fluid, under pressure, in the volume regulator is injected into the sample container using both the fluid trapped pressure and the spring loaded diaphragm.   This cycle then repeats.