As unclesyd indicated, there is more information needed in order to properly respond. Among these would be:
What is the lubricant or material being removed?
What are the pipes and contact materials constructed of?
What delivery methods are currently available? (Are there circulation pumps available in the system that could be used?)
How large a system is it? (Pipe diameter, linear feet etc)
What recovery methods will be used? (remediation, collect and dispose etc)
Are there general or specific safety issues involved? (Flammables, Corrosives, personel issues, environmental etc.)
There are any number of solvent based products that could be used in such a situation. My main concerns would be removal of all residues, hazardous nature of the cleaning product, wetted material compatability (seals, pipes, pumps etc) and disposal issues.
There could also be environmentally friendly products based on natural solvents that could do the job and have the benefit of being non-hazardous.
Any additional information you could supply would be helpful. I'll do the best I can in recommending product types for your application.