Pour point (solidifying point). Mineral oils do not have a melting point but a transition zone between "no longer pourable" and solid. The pour point is specified instead of the indeterminable melting point. DIN ISO 3016 (October 1982) defines the pour point as: "The lowest temperature at which oil can still flow when it is cooled under specific operating conditions." After heating the sample, it is cooled under specific conditions and tested for pourability at temperature intervals of every 3K. The lowest temperature at which the oil can still just about flow is the pour point. A value comparable to the pour point is the solidifying point, which is defined in the withdrawn DIN 51583 (October 1962) as follows:

"The solidifying point of a mineral oil is the temperature at which the oil just stops to flow under the standard's conditions. In the case of dark, mostly high-viscosity heating oils, a distinction is drawn between the top and bottom solidifying point, depending on which analysis method is used." Pourability was tested at cooling temperature intervals of 2K. When sealing mineral oils near their pour point, steps must be taken to ensure they do not fall below this point when in the stuffing box.