Grease Injection Control Head is required to obtain a seal when using braided cable.
Principle of Operation: Grease is injected at a pressure higher than the well pressure (approximately 20% higher). The grease fills the interstitial grooves between the braided line strands. The most critical components of the grease injection head are the ‘flow tubes’. These should be approximately 0.010” ID larger than the measured outside diameter of the line. A seal is effected by pumping grease at slightly above the well pressure. This action causes pressure drop to occur across each tube. The pack off at the top is closed fully in order to gain control of the pressure before running the cable.
Ancillary Equipment:
The following equipment is required to operate the grease injection system
- Grease control head
- Compressor (Back-up system essential in high pressure situations)
- Grease reservoir
- Grease pump
- Connection hoses
- Dual BOP system
Use :
The following factors will effect the volume of grease required :
- Clearance between the flow tubes and line
- Temperature
- Well pressure
- Line speed
- Line size
- Grease viscosity
