Please read our Terms of Use page before using the instructions shown below. Oil Samples Production samples should be collected at the well head . Well head samples are preferable to header samples, because even header samples may be contaminated by leaking valves, corrosion inhibitor, etc. Flush the sampling point, since taps and needle valves are dead spots in the flow stream and may contain non-representative fluids. Samples should be collected in glass bottles or metal cans , avoiding contact with any plastic and avoiding contact with any oil-contaminated sampling equipment.
Plastic bottles contain plasticizers that contaminate the sample.
It is NOT necessary to try to separate oil from water, or to try to break emulsions. Condensate Samples Extra care to avoid contamination should be taken when sampling condensates because they typically have low biomarker concentrations and can be easily contaminated by fluids left in the separator from a previous test. To minimize contamination, start with clean equipment and sample near the end of the test. If a condensate is waxy, it should be sampled near the well head upstream of any suspected wax precipitation in the flow lines. RFT Samples RFT samples are often vented at the surface, thereby losing the gas fraction of the sample.