Developing the Right Oil Flushing Plan

What is the right acceptance criteria to use for oil flushing activities?

For clients, new to the world of oil cleanliness and flushing it is easy to get confused by the nomenclature. Those more seasoned professionals will throw out abbreviated words, acronyms, or API (American Petroleum Institute) Standards; like everyone has read and memorized all 300 pages of each standard. Here at RIG it is our goal to be the technical resource needed in executing flushing services. There is key information needed while developing the right flushing plan for each piece of equipment. Let’s break down each piece.

Does the OEM (Original Equipment Manufacturer) have a specific guideline to use for flushing activities on the rotating equipment? Most OEM’s do have criteria for commissioning and some include general guidelines for maintenance

1. Is equipment under warranty? If yes, OEM specifications supersede API standards. Each OEM is different.
   RIG works with the client and OEM to develop the right plan to meet cleanliness criteria.
2. Has rotating equipment been modified where original OEM specifications are no longer valid? Not a typical situation but not totally unheard of. You would review the modified piece specifications and set criteria to the tightest (most stringent) specification.
3. Has the site or plant developed their own criteria? We have seen this happen with larger corporations who share best practices on a national (and sometimes international) level. This situation usually take place when companies have had failures due to lubrication cleanliness issues. RIG experts have assisted in development and revisions to “Best Practices” alongside these companies. Focusing on prevention first, then executions of flushing during downtime to maintain cleanliness.
4. Is the unit from 50+ years ago and no one has the specifications anymore? Or, is the criteria outdated and no longer best practices? This is the most common situation we run into today. Units from the 1950 and on are still in use today. Far out of warranty and flushing in the 50’s consisted of running some oil through the system and out the other side to disposal.

If you are in a situation with no obvious criteria from manufacturer what is the right direction? There are (5) key documents issue by ASTM (American Standard for Testing and Materials).

1. API 686 – Machinery Installation and Design, Chapter 8 – Lubrication Systems Installation
2. ASTM: D 4174 – Cleaning, Flushing, and purification of Petroleum Fluid Hydraulic Systems
3. ASTM: D 6439 – Standard Guide for Cleaning, Flushing, and Purification of Steam, Gas, and Hydroelectric Turbine Lubrication Systems
4. API 614 – Lubrication, Shaft Sealing and Oil Control Systems and Auxiliaries
5. ISO (International Standard Organization): 10438-1 – Petroleum, petrochemical and natural gas industries – Lubrication, Shaft Sealing and Oil Control Systems and Auxiliaries (Note: ISO10438-1 was developed jointly with API614 and is equivalent to)

The most utilized standard is the API614 for specific acceptance criteria (see example 1.0). All of the listed documents have useful information on what to flush in the system, inspection media, and minimal flow rates. However, these documents do not always take into account newer “Best Practices”. For example, a pneumatic vibrator will shake the pipes without damaging paint or scuffing fittings that “hammer blows” do. Or, in place of system pumps bringing in one of RIG’s high volume flushing skids. Increase volume will eliminate days of flushing utilizing flow to 2-3 times normal operating level. This will develop turbulent flow and a higher Reynolds number than can be achieved with system pumps.

At RIG our goal is to become an extension of your Reliability and Maintenance Teams. Providing that technical expertise in Lubrication Services.

If you would like to learn more about RIG, contact Jason Bandy at info@therigteam.com to schedule a Lunch and Learn at your facility today.

By: Larry Jordan