- Buyer's Guide
It is all too easy to overlook the details when creating an onsite oil analysis program. But these overlooked details may be the difference between a successful onsite oil analysis program and an unsuccessful one.
Typically, the space allocated for a test area is often in some dark and unused area of the plant that nobody else wants. Therefore, it is important to plan from the beginning the amount of space required, what furniture and benches are necessary, and to make provisions for storage, lighting, power and ventilation. In designing the workspace, ergonomics is the key, so that tests may be conducted quickly, simply, accurately and safely.
Making the work area efficient and procedures as simple and painless as possible, will encourage ownership and enthusiasm in the program, and ensure the job is done properly. Keeping in mind that several people may be involved in the program, procedural consistency and good housekeeping are critical to accurate, trendable data. By keeping the workspace, neat, tidy and efficient, both employees and visitors will walk away with the impression that oil analysis is as desirable and critical as any other technology, further enhancing the perceived value of the program.
Once the critical components to be sampled have been determined, the next step is to identify primary and secondary sampling points, and where necessary, install appropriate sampling valves. In doing so, it is necessary to ensure that the right tools are available for the job. A sampling tool kit should contain pliers, adjustable wrenches and a selection of lint-free rags for wiping the sampling ports, as well as the necessary adapters and vacuum sampling pumps required to extract a sample. In addition, there should be some clippers for cutting the tubing for the vacuum pump, as well as a permanent marker suitable for writing labels.
A waste container is also useful, because test ports, tubing, etc., should be flushed at least 5 to 10 times the dead volume, requiring the collection of a significant volume of waste fluid. If possible, the oil flushed into the waste container should be returned to the tank if it is a significant volume, otherwise it should be discarded, obeying all environmental and safety standards. Avoid cross-contaminating the fluids. Having a small cart (or trolley) to carry the toolbox and other equipment is recommended as space permits.
Where portable instruments are used for online testing, a small cart relieves the agony of carrying the instrument over great distances. Such a cart may also require a suitable power extension to be fitted for certain instruments, along with a mount for a data collector unit where necessary.
Sample bottles should be prepared in the test area before going onsite and packed in a clean case, complete with ready-to-apply labels. This ensures that the correct information is on the sample and helps to avoid potential errors through poorly written or incorrect labeling. For sampling components in areas of heavy contamination, the zip-close bag sampling procedure should be used.
The label should include the machine and sample port identities, and space for information about oil hours, machine hours, lubricant brand, type and grade, any make-up oil that may have been added since the last sample, and other information such as a filter change or any visual observations. This will assist not only the analyst onsite, but also the analyst at the laboratory when exception testing is necessary.
Work Area and Health and Safety
The work area is critical to the smooth operation of the program. The comfort of the analyst is a prime concern given the sometimes-tedious nature of the testing. As with any job, giving ownership to the individual responsible will create a strong interest in the program, which may mean the individual is given an active role in the design of the area. It is also important to ensure that the work area is maintained at a constant room temperature and is adequately ventilated. This will minimize inaccuracies, particularly when conducting tests that are sensitive to temperature fluctuations such as viscosity and water saturation.
There should be a workbench at the appropriate height with sufficient work surface in the testing area to allow for instrumentation (typically allow space for double the footprint area of the instrument), and preferably allowing for expansion with further units. Electrical outlets should be provided for the instruments, and in some instances, an air line might be required, as well as ventilation where noxious (or flammable) samples or solvent vapors are anticipated.
A storage area is also needed for incoming samples. It is recommended that tested samples be held for three months in case of subsequent questions, or the need to perform exception testing. Other storage will be required for the portable instruments, consumable materials (such as bottles, tubing, etc.), solvents and reagents, and if relevant, space for the cart and waste containers.
Fluid disposal should be carried out in accordance with local safety and environmental regulations. It is worth requesting a Materials Safety Data Sheet (MSDS) for each lubricant to keep in the office in case questions arise. This serves as a reference for the analyst to check before handling the sample. The MSDS also applies to the chemicals, solvents or reagents used in some tests, which must be handled and disposed of according to standards. It also goes without saying that smoking should be prohibited in this area. A first-aid kit (with eye-wash solution) and fire extinguisher should be easily accessible. It is recommended to install a small sink unit with hot and cold water along with a good hand soap.
In addition to company policy on wearing hard hats and safety shoes when collecting samples, safety gloves and eye protection should be worn at all times. This is especially important when working with online test units on high-pressure systems and when performing tests such as the hot plate crackle test or AN/BN titration. Install a nonslip flooring that is impervious to oil spillage and allows for easy clean up. A concrete floor will look unsightly after a period of time, and is difficult to sweep, which could contribute to airborne contaminant and inaccurate data. For similar reasons, the walls should be painted or tiled to minimize cleaning and dust release.
In the interest of good housekeeping, keep paper towels on hand. Place instruments in a stainless steel drip tray to contain any spillage. A special disposal canister should be used for the disposal of the paper towel. Paper towels should be high quality and lint-free to avoid contaminating the samples.
To avoid creating problems in the future, routine flushing of the instruments after testing should be standard practice by following manufacturers’ guidelines. Build a small recirculating rig to minimize the cost of certain flushing fluids. This is of particular relevance to onsite particle counters.
The rig should consist of a tank, a pump, a small 1-micron or 3-micron filter and a tapping point for dispensing into bottles. For some fluids, an earth strap or grounding line is required to prevent static build-up and the risk of fire. The back flush or drain line from the instruments should be directed to the waste container to avoid contaminating the flushing fluid tank. A supply of environmentally friendly solvents should be kept handy for cleaning the instruments, spillage or diluting heavy samples. Be sure to wear appropriate surgical safety gloves to avoid skin contact with solvents.
When diluting high viscosity samples, dispense the solvent from the canister through a small 0.8 µm membrane filter to avoid adding contaminant to the sample. The best canisters for this are stainless steel, which can be pressurized to allow for easy dispensing. Plastic dispensing units tend to shed particles, and should be avoided if possible. If extreme levels of fluid cleanliness are measured, then consider utilizing a clean-room cabinet. These have a positive pressure displacement to avoid airborne contaminants entering the work area, and should be fitted with suitable air filters. Adequate lighting and good ventilation are also important. In all instances where samples are tested for contamination and wear debris, a paint can
shaker should be used to ensure proper agitation of samples and resuspension of particles prior to testing.
Because many onsite labs are an extension of an existing condition-monitoring program, the data should be used in conjunction with other technologies. As such, it is important to provide a computer to trend the data with other technologies. To facilitate this, network provision is essential to link with other groups and perhaps other sites. Many of the newer instruments now incorporate connectivity via RS232 or similar systems for the upload of data to the computer, so this must be considered when designing the workspace layout. Ideally, a suitable desk should be provided, along with shelving for the storage of files, manuals and textbooks. Wall charts are useful in displaying proper sampling techniques, the shapes of common wear particles, etc., so plan space for these.
Not all of the information discussed here will be relevant to the more basic oil analysis programs, but by carefully planning room for growth and expansion, success with onsite oil analysis will be greatly enhanced. Rather than simply buying an appropriate instrument, think about the long-term goals of your program, give some thought to planning, and reap the rewards that onsite oil analysis can provide.