Procedure for Changing from Mineral Oil to Biodegradable Fluids

Procedure for changing from mineral oil to biodegradable fluids:

As more and more governments are pushing for “green” alternatives, customers may be required to use biodegradable lubricants in their equipment. This is becoming more common in reclamation projects, environmentally sensitive areas, and in some new construction. Important is a correct procedure for changing from mineral oil to biodegradable fluids.

Varnish, sludge, and deposits tend to build up in hot zones and “dead zones” in gear boxes, hydraulic, and hydrostatic equipment. Most mineral oil based products are not designed to clean out a system and will leave all the undesirable stuff behind when the fluid is drained. When a biodegradable fluid is introduced, it acts like a solvent throughout the system cleaning out the varnish, sludge and deposits which in turn clogs filters, valves and tight pathways. Final result is poor performance and an unhappy customer. Some additives present in gear, hydraulic or hydrostatic oils are not compatible with biodegradable fluids and gelling or other undesirable problems may occur.

By following this procedure, you will greatly reduce potential problems or issues that may arise due to switching fluid types.

1. Prior to changing the fluid, add SWEPCO 728 In-Service Cleaner at 1 to 16 to the sump, do not overfill the reservoir or sump. It may be necessary to remove some fluid from the sump to accommodate the 728.
2. Operate the equipment at normal operating temperatures and pressures for 30 to 60 minutes.
3. While still hot, drain out all of the old fluid completely. This includes disconnecting hoses, cylinder drains and filter.
4. Fill the sump ½ full with SWEPCO 729 Flush and operate the system:
   • Fill the system with SWEPCO 729 Premium Flushing Oil.
   • Operate at no load or at minimum pressure, then, slowly bring the fluid up to normal temperature and operate all parts.
   • Operate only long enough to insure complete circulation of flushing oil. (Most gear boxes can be filled to one-third their normal capacity and operated at no load for 10 minutes.
   • If the initial drain oil was severely Oxidized, drain and refill again to one third capacity and run no load for 15 minutes.
   • If a one-third fill would be insufficient to insure proper splash or circulation of lubricant in a gear box, then a full fill to normal capacity can and should be used.)
   • Systems that were previously lubricated with synthetic fluids should be operated for no longer than two to eight hours.
   • Carefully observe operating temperatures, filters and inlet screens while operating on flushing oil and shut down if filters plug or temperatures exceed normal no load limits.
   • When the flushing cycle has been completed, drain the flushing charge as completely as possible while it is still warm and without allowing it to settle.
5. Drain the sump, hoses, cylinders, and filters.
6. Fill the sump ½ full with SWEPCO 737 EcoPro Anti-Wear Hydraulic Oil and repeat flush procedure.
7. Drain the sump, hoses, cylinders, and change the filters.
8. Fill to the recommended level with SWEPCO 737 and operate normally.
9. Check the system daily for the first week for leaks, increases in operating temperature or pressures, and any performance issues.
10. If any issues occur contact your Sales Manager for further instructions.

This procedure should clean out varnish, deposits, and old fluid from the system. Following this will reduce compatibility issues and prepare the system for the new fluid. This procedure can be used when changing fluid types and even the same type from different suppliers.

As always please contact your SWEPCO agent if you have any questions.

Source: SWEPCO®
Southwestern Petroleum Corporation®