Changing Lubricant Brands, Murphy’s law applicable?Stratson
Changing Lubricant Brands, Murphy’s law applicable?
One of the most frequently asked questions we receive concern the changeover from brand X to SWEPCO products. All new and many current customers must weigh the risks that may occur when switching Brands due to possible incompatibilities and others potential issues. Contrary to popular belief not all lubricants are the same and Murphy’s law “Anything that can go wrong will go wrong” still shows up at the most inopportune times.
There are a variety of reasons to change lubricant suppliers such as:
- Companywide lubricant supplier change;
- Unsatisfactory historic performance;
- Reduced lubricant cost through extended drains or initial price;
- Current product has been discontinued.
Base fluid compatibility
One of the major issues concerns base fluid compatibility. There are several suppliers that use glycol, silicon, or ester based synthetic fluids for long life compressor fluids, turbine lubricants, and other applications. These fluids are usually not compatible with mineral oil, PAO’s, or other fluids so they must be thoroughly cleaned out of the system prior to the final fill with new SWEPCO lubricants. Fluids will gather in trapped cavities such as heaters, coolers, off-line loops, hoses, filters, low –point traps, line extensions, etc. Even after a drain is complete, oil will still cling to internal metal surfaces especially if there are sludge or varnish deposits.
Why SWEPCO 728 & SWEPCO 729?
It is also recommended that hoses, seals, and filters be changed after flushing. Most hose materials will absorb fluids during use, and then expel them when a different fluid is introduced, causing compatibility issues, leaks, and downtime. Glycols have been known to react with the additives in mineral oils and form a gelatin like material that can clog filters and oil ways. This can lead to lubricant starvation and failure. It is highly recommended that an oil flush such as SWEPCO 729 be completed according to directions prior to using a new fluid. If sludge or varnish is present, then using SWEPCO 728 with the SWEPCO 729 is recommended to remove these contaminates followed by a second flush with SWEPCO 729.
Additive compatibility is a possibility when switching brands with similar base fluids, i.e. mineral oil to mineral oil. Some additive packages may react to form sludge or other deposits and shorten the life of the oils. This is why it is recommended that you always top off with the same oil that is in the system in between changes.
If sludge, varnish or other deposits are present it is highly recommended that SWEPCO 728 be used according to directions prior to draining the old fluid to help remove these deposits. Introducing a different fluid may clean up deposits that will circulate until the next drain interval. If these deposits are left in the system for a long period of time they could cause wear, leaks, filter plugging, and other issues. One way to determine if there is a compatibility issue is to make three blends of the old and new oils, 10:90, 50:50, and 90:10. Warm these blends to 49°C to 55°C (120°F to 130°F) and allow to cool to room temperature. Any separation, sediment, cloudiness, or discoloration could mean that there is a compatibility issue. Of course you can always call your agent or distributor for guidance.
Monitoring is highly recommended
Finally after a changeover has been completed, follow up monitoring is highly recommended to help prevent equipment failures. These may include early oil analysis, machine inspections, and fluid inspections. The inspections would consist of looking for foam, cloudy fluid, high temperatures, noisy operations, and discoloration. Remember to change lubrication procedures and supply to include the new lubricant for top-ups and future oil changes.
This information is provided so that you will be aware of possible issues and concerns you may have regarding changing lubricant brands and/or when switching to SWEPCO products. Using this information you have been informed on the precautions, recommendations, and procedures to make a successful changeover.
When changing lubricant brands, Murphy’s law applicable? Absolutely not, when correct steps are followed!
As always, check the EOM requirements, current lubricant, and operating conditions prior to making a change and you can always contact your agent or distributor for guidance and suggestions .