Abstract: For reducing the restart pressure of streams selected from waxy crude oils, water-in-crude emulsions and dispersions of hydrocarbon hydrates, at least partially structured, a mechanic disturbance is applied, in flow-stop conditions, on the streams. The temperatures are lower than the WAT (Wax Appearance Temperature) for the waxy crude oils and water-in-crude emulsions. The temperatures are also lower than the forming temperatures of the hydrates and pressures higher than the forming pressure of the hydrates, for the dispersions of hydrocarbon hydrates.

Abstract: For reducing the restart pressure of streams selected from waxy crude oils, water-in-crude emulsions and dispersions of hydrocarbon hydrates, at least partially structured, a mechanic disturbance is applied, in flow-stop conditions, on the streams, The temperatures are lower than the WAT (Wax Appearance Temperature) for the waxy crude oils and water-in-crude emulsions. The temperatures are laso lower than the forming temperatures of said hydrates and pressures higher than the forming pressure of said hydrates, for the dispersions of hydrocarbon hydrates.

Abstract: A process for reducing the restart pressure of streams selected from waxy crude oils, water-in-crude emulsions and dispersions of hydrocarbon hydrates, at least partially structured. A mechanic disturbance is applied, in flow-stop conditions, on the streams, having: temperatures lower than the WAT (Wax Appearance Temperature) for the waxy crude oils and water-in-crude emulsions; temperatures lower than the forming temperatures of the hydrates and pressures higher than the forming pressure of the hydrates, for the dispersions of hydrocarbon hydrates.

Abstract: A process for reducing the restart pressure of streams selected from waxy crude oils, water-in-crude emulsions and dispersions of hydrocarbon hydrates, at least partially structured. A mechanic disturbance is applied, in flow-stop conditions, on the streams, having: temperatures lower than the WAT (Wax Appearance Temperature) for the waxy crude oils and water-in-crude emulsions; temperatures lower than the forming temperatures of the hydrates and pressures higher than the forming pressure of the hydrates, for the dispersions of hydrocarbon hydrates.

Abstract: Composition of lubricating oil which comprises: a) a greater portion of synthetic lubricating component or a mixture of synthetic lubricating component and a mineral base for lubricating oils, the synthetic lubricating component being prepared by the oligomerization and subsequent hydrogenation and the possible removal of low-boiling by-products, of a composition of olefins basically consisting of:1) a mixture of n-olefins having a content of olefins from C.sub.14 to C.sub.17, preferably from C.sub.15 to C.sub.16, of at least 80%, preferably greater than 85%,2) alpha olefins from C.sub.15 to C.sub.17, preferably basically C.sub.16, the content of the alpha olefin (2) being from 5 to 25% by weight, preferably from 10 to 20%, with respect to the sum of (1)+(2).