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The Functions of Zerk Fittings

In aircraft and other heavy-duty vehicles, grease is crucial to carrying out preventive maintenance. A majority of mechanical parts regularly require proper lubrication for functionality and protection, and a zerk is a component necessary for greasing aircraft and other vehicles. A zerk is a fitting that permits you to inject grease lubricant into points where wear occurs on cars, trucks, aircraft, and more. It is like a one-way valve in which grease is implemented, promoting smooth movement of parts and more effective handling by keeping grease within a mechanism.

Another benefit of zerk fittings is that they make it possible to apply grease to specific areas rather than all over a mechanism. To do this, they rely on a design that consists of a nipple with a metal ball that has been placed at the end of a spring. When the fitting is pressed by a grease gun, the spring compresses, removing the ball from the nipple and allowing grease to flow into the mechanism.

Zerks typically feature a variety of angled configurations, such as 30-degree, 45-degree, and 90-degree angles, and they are typically made of metals like brass or stainless steel with finishes that include nickel and zinc. Moreover, they are available in a number of different styles such as ball-check, pin-type, and self-tapping zerks.

To lubricate aircraft mechanical parts, a few different tools are necessary, including a standard grease gun, fitting rejuvenator, and extra zerks. Standard grease guns hold an entire tube of grease, and they are designed to help you reach the right angle to press grease into inflexible fittings. Many also have swivel heads and long hoses to make zerk lubing easier in tight spots. Another important tool is a fitting rejuvenator which helps bearings and zerks avoid being stuck in the opening after experiencing a stint without lubrication. To use the fitting rejuvenator, you fill it with grease, place it over the zerk, and strike it using a hammer to knock the bearing loose again. The process of lubing zerks can sometimes damage them, which is why it is a good idea to bring extras along with you.

When you are lubricating a zerk, there are several precautions you should take. First, it is important to make sure the fitting is clean before attaching the grease gun to keep dirt from getting into the fitting. Once this is done, one must pump in grease until they notice increased resistance. For safety, you should always be working alongside a lubrication diagram for reference, especially when you are unfamiliar with the particular equipment you are servicing. Furthermore, be sure to mark the zerk fitting with the type of grease being used and avoid changing that type in the future if possible. Lastly, always keep the grease gun clean and covered at all times when it is not in use.

Properly greasing and working to upkeep zerk fittings is crucial to ensure the safety of an aircraft, and their role of lubricating and promoting smooth operations is a foundational component of aircraft maintenance. When you are searching for top-quality aircraft parts of any type, you can count on Stacked Purchasing to assist you through the procurement process. Once you take the time to browse through our expansive catalog and discover items of interest, we encourage you to take advantage of our RFQ service by requesting a quote for your comparisons. Our team will get back to you with a customized solution within 15 minutes of receiving your detailed request. To learn more about how we can serve as your strategic sourcing partner for all your part needs, call or email us today!


November 29, 2022
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