When operating properly, vacuum pumps can improve the efficiency and consistency of manufacturing machinery onsite. However, to appreciate their benefits, pumps must always be regularly maintained. An important part of vacuum pump maintenance includes checking and changing the oil they use. Read on to learn more.
Why does vacuum pump oil need changing?
Vacuum pumps use oil to move liquid and air and to process any byproducts present. The oil is vital to achieving optimum performance, but the process of changing pump oil is disruptive. Change intervals temporarily take the system out action, causing lags in productivity. As a result, many operators are tempted to skimp on routine oil changes or in some cases miss them out entirely. However, that consequence of such inaction can cause machinery to fail faster than normal as well as introduce unwanted process variability. When vacuum pump oil degrades, it can affect the vacuum levels, resulting in lost production and profits.
When should you change vacuum pump oil?
The initial resource to refer to when deciding whether to change the oil in your pump is your equipment manual. When companies purchase a vacuum pump, it will typically arrive with a manual that lists necessary maintenance schedules (including oil change intervals). Experts recommend that vacuum pump oils should be changed after approximately 500 hours. However, it is important to remember that oil changes could be required more frequently than recommended depending on application.
There are specific circumstances and signs that oils in vacuum pumps should be changed earlier. If the vacuum pump has been out of use and in storage for some time, a change is advised but the colour of the oil and the way it looks can also show you if you need to refresh your system with new lubricant.
Why oil colour and appearance are key
A strong indicator of whether to change vacuum pump oil is by looking at its colour. Typically, it should appear light in colour, but there are a range of different shades which are acceptable and at which your machinery will still function. As a rule, when you are checking the vacuum pump oil and find it’s at shade number four or darker, it’s high time your drained off the old oil and replaced it with a fresh supply.
Colour isn’t the only indicator; the oil’s overall appearance can also offer information. Vacuum pump oil should be mostly clear and viscous. If you are assessing the oil in your pump and it looks either frothy or milky, it might indicate that condensation has become mixed with the oil or that you have a leak within the system. If this occurs, oils should be drained, and your system checked for any leaks. Once you are sure your system is leak-free, you can then refill it with new vacuum pump oil.
How do you change vacuum pump oil?
Ensure that the vacuum pump has reached operating temperature before you change the oil. To maximise oil drainage, it should have been running for at least half an hour. Next turn off the vacuum pump and extract the oil drain plug. Remember that the oil will be extremely hot so wear protective gloves or keep your hands well clear.
Drain all the fluid from the vacuum pump. Allow the used lubricant to drain into an appropriate container. Tilting the pump can improve the drainage process, but some oil will always remain inside the pumping chamber.
When a vacuum pump features an external oil filter, you can replace it using a dedicated oil filter wrench. Remember to lubricate the rubber seal with a little of the fresh oil and then install a new oil filter. Be mindful not to overtighten the filter.
After you have drained the old oil, you can refit and then tighten the pump’s oil drain plug. You can now refill the pump using the specified oil grade recommended by your original equipment manufacturer (OEM). Always add the lubricant slowly while keeping the vacuum pump level.
You should fill the oil up to the centre of the vacuum pump’s sight glass or, if present on your make and model, the specific fill line. Never overfill it.
Now you can reinstall the pump’s oil filter plug and then tighten it up. Turn on the vacuum pump and make certain that the oil level stays below the top of the pump’s sight glass. Check both the oil filter and the drain plug for any signs of leaks while the pump runs around 15 minutes. Operate the pump for another two hours and check your oil level in the sight glass. Top it up with more oil if required.
Oil changes in vacuum pumps are crucial to keep systems running smoothly and enhance productivity. If you are unsure when to conduct this maintenance, always check your owner’s manual and the colour and appearance of your vacuum pump oil.