Fluid Leak Control…
Just how much fluid could be saved if hydraulic system leaks could be completely eliminated? The number is estimated to be in the hundreds of millions of gallons per year. Although this number may seem high at the outset, consider all of the components which use hydraulic fluid, such as sumps, pumping systems, gear cases and hydraulic machines. Approximately 80 percent of oil loss can be attributed to failure of O-rings, fittings, spills, hose breakage and general leakage.
The problem of leakage is so prevalent, in fact, that in just one year, your plant could be using 4 times the oil that your machines hold. So what can be done to control fluid leaks? This depends on where leaks originate, as well as on the knowledge about component design held by engineers, and the level of training maintenance personnel receive.
Knowing where leaks occur
Your first line of defence when trying to control leaks is knowing possible leak points. The failure of hydraulic seals and O-rings are common leak sources, as are vessels and lines which have become corroded, damaged or have ruptured. Gaskets and pipe joints are another common location of fluid leaks.
Common mistakes made prior to leakage
The most common, yet overlooked cause of leakage, is using an O-ring material unsuited to the application. Should a designer choose seal materials that are inappropriate due to temperature range underestimation, this can cause imminent seal failure and subsequent leakage to occur.
Mistakes can also be made at the component size selection stage. The use of incorrectly sized components is one of the biggest causes of external fluid leakage. Similarly, poor installation and improper application also cause significant fluid loss.
Even if the right components are selected and installed, fluid loss can still occur via improper or inadequate maintenance of the hydraulic system. Not filling the system according to manufacturer instructions can cause overfilling and leakage, as can over-torqueing gaskets. Not ensuring vents are unplugged can cause leak-forming pressurisation, and not checking seals on a regular basis can cause wearing and eventual leakage as well.
Common mistakes made after leakage has occurred
There are also several mistakes which can be made following the failure of a component and fluid leakage. The first step after a seal has failed is to purchase a new one. However, all too often a low-quality seal is purchased, or the incorrect seal chosen.
Mistakes can also be made during installation or replacement of seals. Although they may not be significant, the resultant fluid leaks will be ongoing. If left unchecked, leakages can be considered to be a normal part of equipment operation, instead of the problem that they are, leading to significant fluid loss over time.
Leak detection and containment
There are several ways to confirm that fluid leakage is occurring. It may be that visual inspection is enough to detect leaks, but they can also be found using oil records or dyes.
How to contain a leak will depend on the leak location and the volume of oil being lost. Small leaks may only require peat moss or loose granular corn to prevent spreading, while more significant leaks may require pillows, absorbent pads or dikes to be installed.
Is it worth it to try and stop fluid leakage? In a word, yes. Leaks can be stopped up to 75% of the time. However, to ensure complete leak prevention, better decisions must be made at every level of the process, from component design and engineering to knowledgeable component purchases and the effective use of materials.