by Robert L. Matthews
Savings with water use reductions can be huge. And, today, especially in the Atlanta area where drought recently left reservoirs high and dry, water is precious and should be conserved everywhere.
Cost savings add up and can finance a lot of the reliability programs as you start. Documentation is the key to its success at start-up and through a reliability maintenance life.
We cool pumps and other equipment with water but often don’t understand the cost for the wasted water or from damaging equipment when we incorrectly cool with water. Savings from the thousands of dollars to the millions have been documented in the industry where plants employ their water cost savings efforts more effectively.
First, the cost of water can be expressed as $2,000 per year for a ½” stream of water. What we need to do is control water usage and document the savings. Yes, it’s time to put some money back in the company pocketbook.
The water to cool equipment should be slowed down such that discharging water is kept at a minimum, warm to the touch. This year, at the NPRA Reliability & Maintenance Conference, Heinz P. Bloch spoke about routine shop upgrades and said cooling water is to be removed from centrifugal pump bearing housings with rolling element bearings. Some of his presentations and books can be found online. Many, such as Process Plant Machinery and Machinery Component Maintenance and Repair, are resources any maintenance organization should have in their library.
Next, too many plants misapply water to industrial braided packing and mechanical seal systems. Water that flows through packing lantern rings is to be 10# to 20# above the stuffing box pressure – and, in most plants, there’s no gauge to show this. Consequently, the passing-through-water is wasted and causes other damages and costs. This includes the packing (it burns up), the sleeve (it wears out), and the process, for which leaks often waste product and create potential safety issues.
We all have to do our part today to save our water and improve plant reliability. That improves the operation’s competitiveness and employee job security.
About the Author: Reliability manager for Houston-based Royal Purple Ltd., Bob Matthews has 35-plus years of pump industry experience – from hands-on to supervision – in plant maintenance management, consulting and training.