Apparatus for coating internal surfaces.

摘要

A plasma spray apparatus adapted for coating an irregular internal surface (103) of a tubular object (101) in which the spray apparatus has a nozzle (140) for directing the coating material on the internal surface (103) of the object (101) and wherein a central spray axis (109) drawn through the centre line of the nozzle (140) comprises: (a) a plasma torch (105) having a spraay nozzle (140) (b) first arm means (111) attached to the torch (105) (c) second arm means (121) attached to the first arm means (111) (d) third arm means (131) attached to the second arm means (121) (e) moving (147,149) and rotating means (151) connected by a shaft (153) in suitable stiff bearings (155) and connecting means (157) to the outer end of the third arm means (131) for moving the first arm means (111), second arm means (121), and third arm means (131) to effect movement of the spray nozzle (140) in a direction parallel and in the direction perpendicular to the longitudinal axis (101a) of the tubular object (101), and for rotating (159) the spray nozzle (140) about a rotational axis (145) so that the central spray axis (109) is directed perpendicular to the impingement point (107) on the internal surface (103) of the tubular object (101); and (f) conventional co-ordinating means for co-ordinating the movement and rotation of the spray nozzle (140).