HALLIBURTON ENERGY SERVICES is one of the world's largest diversified energy services, engineering, maintenance and construction companies.

Here in the Duncan Okla., manufacturing plant, Halliburton Energy Services operates approximately 250 metalworking machines - mills, drills, lathes, saws, machining centers, and grinders. All of the machines have individual sumps, with the average coolant capacity being 200 gallons.

Over several years, Halliburton had concerns about the performance of the plant's machining coolants. Waste disposal, poor sump life, "Monday morning stench", rancidity, machine down time, and operator acceptance were prominent problems. The company also had a desire to optimize its competitive posture through increasing efficiency and cost effectiveness. To address the problems associated with machining coolants, a Coolant Control Team was formed in 1990. The team consisted of a coolant coordinator, five shop representatives and one manufacturing engineer. The mission of the Team was to solve the plant's coolant problems in a stepwise fashion:

• First, develop training programs and assign specific responsibilities.
• Next, utilize existing equipment to maximum advantage.
• Then, select coolant(s) best suited for the plant's work.
• And finally, bring in new technology as needed to optimize the coolant management process.

Training programs, along with assignments of specific responsibilities, resulted in some early savings with respect to the frequency of sump clean-outs and occurrences of rancid coolant.

The company owned a coolant recycler that it had purchased in 1985. This recycler included a centrifuge and an ultra-filtration unit.

Shortly after its formation, the Coolant Control Team put these two processes to work separately: the ultra-filtration unit to remove water from spent coolant, and the centrifuge to clean coolant that was not completely spent. Cleaned coolant was treated with biocide, mixed with fresh coolant and placed back into circulation. Sludge from the centrifuge, along with any spent coolant, was passed through the ultra-filtration unit. These programs resulted in $115,000 savings in disposal costs in 1992.

In late 1992, the Coolant Control Team was replaced by a Coolant Management Team consisting of a coolant coordinator, a manufacturing engineer, and one shop representative.

At that time, a water soluble oil was being used as coolant in over 90 percent of the machines in the plant. The grinders used a synthetic coolant. As the demands on coolant performance continued to increase, especially as it pertained to increased usage of exotic metals, the Coolant Management Team concluded that a better coolant might add to performance.

The team designed and conducted a testing procedure to select another coolant. A semi-synthetic coolant was selected and , excepting grinders, the plant was converted to the new coolant by early 1994. (The grinders continue to use a synthetic coolant.) Annual usage was reduced by 50 percent and the coolant is still in use today.

In 1994 and 1995 other major technologies contributed to further significant reductions in the overall cost of the coolant program. An evaporation unit was designed and built internally to help reduce the volume of coolant waste. And the plant adopted the "0" Waste System from BioTech International Inc. of Sugar Land, Texas.

The "0" Waste System is a management program that focuses on controlling the root cause of coolant spoilage - bacterial activity. Record keeping and tracking of trends are part of this system. Daily tests on the coolant concentration are performed and fresh coolant is added as dictated by the test results.

The "0" Waste System includes a biological testing device that makes it possible to test the bacterial activity in the sumps, and have the results in 15 minutes. A non-biocidal stabilizer, the BioTech MARK II, is added, if indicated by this test. The frequency at which biological testing on particular sumps is conducted has been reduced to once every two weeks.

The "0" Waste System also includes portable filtration units that are moved from machine to machine to remove machine fines and other contamination. The Duncan plant utilizes five of these units to service the entire machine shop. The units run unattended, cause no machine downtime, and are moved every two to three hours. If, for some reason, disposal of coolant should become necessary, it is removed to a holding tank where it is fed into the evaporator.

The "0" Waste System, along with the evaporator, has reduced the overall cost of waste disposal by reducing the volume by 95 percent. Recording and reviewing the data from this program allows the Coolant Management Team to focus its efforts on areas of the plant where their services are needed most.

Bottom-line results from the changes made at our Duncan plant include a reduction in the spent coolant disposal cost of $450,000 per year, and is ongoing. Further savings have been realized in the volume of new fluid concentrate, and the amount of labor necessary to maintain the coolant. Sump life on some machines has exceeded one year, as compared to seven weeks previously.

In conclusion, it may be said that the technology exists to solve a diversity of coolant problems, resulting in significant cost savings, labor savings and creating a more pleasant work atmosphere. The successes enjoyed at the Halliburton Duncan plant were made possible largely by the commitment made by company management to have the cleanest, most efficient operation possible, and then empowering the team(s) to find and implement the means to achieve the desired results.

The Coolant Management Team remains active and continues to search for ways to increase plant efficiency.