Abstract: A liquid/gas helical separator operates on a combination of centrifugal and gravitational forces. The separator includes a primary separator formed basically by an expansion chamber, a secondary separator formed basically by a helix for directing the flow, a tertiary separator which consists of a reservoir or gravitational-separation tank and of a transition region between the primary and secondary separators, which consists of at least two variable-pitch helixes whose inclination varies from an angle of 90.degree. to the angle of inclination of the constant-pitch helix of the secondary separator with the function of providing a gentler flow of the liquid phase at the transition between the first two separators.