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As the primary well control barrier, our industry-first Elmar™ Enviro™ grease injection control head creates a seal around a moving wireline, giving positive protection and allowing intervention access to wells under pressure
Engineered to minimize environmental impact by ensuring optimal line wiper element positioning and performance, the Enviro assembly maintains a clean working environment for operations and personnel around the wellhead.
With an integral and replaceable check valve that eliminates well pressure return to the injection unit, the Enviro grease injection control head’s tulip design prevents wireline damage during pressure control rig-up whilst its replaceable manifold block ensures that the integral check valve is fully protected.
Positioned at the uppermost point of the pressure control equipment string, the Enviro™ grease injection control head comprises two major sub-assemblies—the Enviro combination stuffing box and line wiper and the flowtube assembly.
The hydraulic stuffing box is designed to pack off on a stationary wireline using a pack-off rubber while the hydraulic line wiper removes the excess grease from a moving wireline.
The grease injection head is supplied with concentric flowtube assemblies as standard, with an inner flowtube sized to fit tightly around the wireline and an outer sleeve to support the assembly.
The number of flowtubes and injection points is dependent on expected well pressure and well fluids, with a recommended flowtube to wire clearance of +0.003 to 0.005 in. optimum and 0.008 in. maximum.