What thread has a grease nipple?

Grease nipples undoubtedly belong to the category of "small parts with a significant impact." These compact yet essential components play a crucial role in maintaining machinery and vehicles. Whether it’s thread lubricants or drive-in grease nipples, their simple yet ingenious design allows for precise lubrication at critical points, ensuring the smooth operation of various systems. They are particularly vital in industries like construction and agriculture, where their presence is ubiquitous.

Drive-in grease nipples are typically installed using a hammer and a bit of force. However, many grease nipples also feature a thread, which becomes highly relevant when it comes to replacements. If you're looking to find the right grease nipple thread tap without wasting too much time, we’ve compiled all the necessary details for you below.

Why Does the Thread Matter on a Grease Nipple?

Grease nipples themselves are maintenance tools, but they require regular upkeep as well. Operating in dirty, dusty, and harsh environments, grease nipples accumulate grime over time, necessitating frequent cleaning or replacement. The thread on the grease nipple ensures a secure and reliable connection to the machine component, allowing it to stay firmly in place during use. Moreover, the thread enables easy removal and reinstallation when servicing is required. If you’re unsure about the thread type while replacing a grease nipple, don’t worry—our guide will help clarify things.

The Thread Varies Based on the Grease Nipple Type

Ideally, each grease nipple type would correspond directly to a specific thread type and size—but unfortunately, it isn't that straightforward. To determine the appropriate thread, start by identifying the grease nipple type, as this information provides valuable clues.

Common Types of Grease Nipples

There is a wide variety of designs, but three types of grease nipples are most commonly used:

• Cone grease nipples according to DIN 71412
• Flat grease nipples according to DIN 3404
• Funnel grease nipples according to DIN 3405

Of these three types, the cone grease nipple, recognized by its rounded head, is the most widely used. Flat grease nipples, with their flattened heads, and funnel grease nipples, featuring a funnel shape, are less common but still popular. While the visual differences between these types are apparent, understanding how they relate to the thread requires deeper exploration.

Cylindrical vs. Conical Threads

Based on the type, you can determine whether the grease nipple thread is cylindrical or conical. Cone grease nipples typically have a conical or tapered thread. Meanwhile, flat and funnel grease nipples generally feature a cylindrical thread. This distinction helps narrow down the possibilities.

The Most Common Threads for Grease Nipples in Germany

Next, we need to differentiate between metric and imperial threads on grease nipples. With both pieces of information, you can accurately identify the thread, assuming the component is German-made. Globally, things become more complex, but let’s break it down step by step.

Metric Grease Nipple Threads

Metric threads dominate on grease nipples, with two main types depending on whether the thread is conical or cylindrical.

Conical Metric Thread on the Grease Nipple

This type of grease nipple typically features a conical metric thread as per DIN 158. It has a flank angle of 60° and a cone of 1:16. The thread designation starts with the letter M, followed by the nominal diameter and pitch, along with the suffix "keg." For instance, M 6x1.0 keg.

Metric Fine Thread on the Grease Nipple

When the grease nipple has a cylindrical thread, it is usually a metric fine thread MF. Similar to the conical variant, it has a flank angle of 60°, and the thread designation includes the nominal diameter and pitch.

Imperial Grease Nipple Threads

Imperial threads on grease nipples often resemble familiar pipe threads.

Cylindrical BSP Thread

The BSP thread on the grease nipple is a cylindrical Whitworth pipe thread, also known as British Standard Pipe Parallel (BSPP) in the UK. Its thread designation combines the letters BSP and the nominal diameter in inches.

Conical R Thread

This is another familiar Whitworth conical pipe thread, British Standard Pipe Tapered (BSPT). It is identified by the letter R followed by the outside diameter in inches.

International Variations of Grease Nipple Threads

Besides the four common threads you’ll encounter frequently in Germany, there are international alternatives worth knowing. These are particularly relevant when working with components from the USA or other countries. American Unified National Fine (UNF) and Unified National Extra Fine (UNEF) fine threads are common, as are American pipe threads like National Pipe Taper Fuel (NPTF) and Pipe Thread Fuel (PTF), with 1/8" NPT being the most prevalent grease nipple thread size. Another lesser-known but frequently encountered option is the SAE-LT thread from the Society of Automotive Engineers.

How to Identify the Right Grease Nipple Thread Tap

To figure out which thread your grease nipple uses and what thread tap you need, you have multiple approaches. Follow these three steps to determine the thread:

1. Determine whether the thread is conical or cylindrical.
2. Identify the pitch by comparing it with a template or a screw with a known pitch.
3. Measure the outside diameter.

These factors should help you pinpoint the exact thread.

For those who work with grease nipples regularly, an identification aid—a rectangular card with threads of all standard sizes—can be incredibly useful. You can simply screw the grease nipple onto the card to see which thread fits. Alternatively, self-tapping grease nipples can create their own thread upon installation, ensuring compatibility. If you’re still uncertain, feel free to reach out to us—we’re experts in thread taps and can assist with any questions regarding grease nipple threads.

At the BAER Online Shop, you’ll find a perfect match for every grease nipple thread. Check it out today!