The Grease Injection Control Head is the part of the wireline pressure control equipment and designed to perform a wireline sealing function for test. It is used for wireline sealing. The Grease Head creates a reliable seal between the interior of grease tubes and the outer diameter of the wireline.

Grease Injection Head comprises two major sub assemblies: the stuffing box or pack off and the flow tube assembly. The flow tubes are close tolerance fitting around the wireline. Along with the flow tube sleeves, they form the main length of the grease injection control head. This length provides sufficient column height when in service to form an effective grease seal.