The present invention describes a sampling system and densitometer system for sampling fluids from a pipeline. A flow loop is set up which continuously collects fluid from the pipeline and then returns the fluid with a minimum fluid flow rate so that the fluid is representative of fluid flowing through the pipeline at the time of sampling. For each sample, pressurized fluid is taken from the flow loop and directed to a pressurized sampling chamber. The sample is then directed by gravity to a removable sample container, which may be pressurized or unpressurized, in each sampling cycle.