Abstract: In a device for optically measuring the external-thread profile of a pipe, comprising a support for the pipe to be measured and an optical measuring unit including at least one measuring device comprising a light source and a camera arranged in the optical path of the light source for recording a silhouette image of the external-thread profile, wherein the optical measuring unit is, in particular rigidly, mounted on a carrier element pivotally held about three spatial axes, the optical measuring unit comprises at least two measuring devices whose optical paths cross each other.

Abstract: A screw joint has a tubular element with a female thread and a tubular element with a male thread, wherein the male thread and the female thread have first contact surfaces that cooperate with each other, and the tubular elements optionally have second contact surfaces adjacent to the female thread and/or the male thread, wherein the first contact surfaces and the optional second contact surfaces each have a coating including a first and a second layer, wherein the first layer is formed as a conversion layer in each case, one of the first contact surfaces that cooperate with each other has a second layer made of ceramic material with a friction reducing effect and the other of the two contact surfaces that cooperate with each other has, as a second layer, a varnish layer with a binding agent made of an organic polymer throughout which solid lubricant particles are distributed.

Abstract: In a device for optically measuring the external-thread profile of a pipe, comprising a support for the pipe to be measured and an optical measuring unit including at least one measuring device comprising a light source and a camera arranged in the optical path of the light source for recording a silhouette image of the external-thread profile, wherein the optical measuring unit is, in particular rigidly, mounted on a carrier element pivotally held about three spatial axes, the optical measuring unit comprises at least two measuring devices whose optical paths cross each other.

Abstract: A screw joint has a tubular element with a female thread and a tubular element with a male thread, wherein the male thread and the female thread have first contact surfaces that cooperate with each other, and the tubular elements optionally have second contact surfaces adjacent to the female thread and/or the male thread, wherein the first contact surfaces and the optional second contact surfaces each have a coating including a first and a second layer, wherein the first layer is formed as a conversion layer in each case, one of the first contact surfaces that cooperate with each other has a second layer made of ceramic material with a friction reducing effect and the other of the two contact surfaces that cooperate with each other has, as a second layer, a varnish layer with a binding agent made of an organic polymer throughout which solid lubricant particles are distributed.