What thread has a grease nipple?
Grease nipples clearly fall into the category of "Small part with a big impact." Whether it's thread lubricants or drive-in grease nipples, with a mechanism that is as simple as it is ingenious, they enable quick lubrication exactly at the right place, thus facilitating the maintenance of numerous machines and vehicles. They are indispensable, especially in construction and agriculture, and can be found in many locations.
Drive-in grease nipples are installed with a hammer and a bit of force. In most cases, however, a thread is present on the grease nipple. This fact can become important quite quickly when you want to replace a grease nipple. To help you find a suitable grease nipple thread tap without much searching, we have compiled all the important information for you here.
Purpose of the Thread on the Grease Nipple
Grease nipples are tools for maintenance, but they also need maintenance from time to time. Their oily task and the demanding working environment amid dirt, dust, and adverse weather conditions make it inevitable that you regularly clean or replace grease nipples – in these cases, the threads on the grease nipple come in handy. The thread on the grease nipple ensures a secure hold and a reliable connection to the component at all times. Additionally, thanks to the thread, the grease nipple can be easily unscrewed and screwed back on. A problem arises when you want to perform a replacement and are not sure about the thread size of the grease nipple – our tips can help you here.
The Thread Depends on the Grease Nipple Type
Of course, it would be nice if every grease nipple type were firmly assigned to a thread type and size – unfortunately, it's not that simple. When looking for the appropriate thread, you should first determine the grease nipple type, as this information provides a clue.
Types of Grease Nipples
The range of designs is large, but three types of grease nipples are most common:
- Cone grease nipples according to DIN 71412
- Flat grease nipples according to DIN 3404
- Funnel grease nipples according to DIN 3405
Among these three types, the cone grease nipple, recognizable by its rounded head, is the most widespread. Flat grease nipples, on the other hand, have a flattened head, and funnel grease nipples have a funnel shape. The most common types are visually distinguishable, but how does this help us with the thread?
Cylindrical and Conical Threads on the Grease Nipple
Based on the type, you can determine whether the grease nipple thread is cylindrical or conical. The thread on the cone grease nipple is conical or tapered. Flat grease nipples and funnel grease nipples, on the other hand, have a cylindrical thread. This already takes us one step further.
The Most Common Threads on Grease Nipples in Germany
Now we still need to differentiate whether the thread on your grease nipple is metric or imperial. With both pieces of information, you can then reliably determine the grease nipple thread, as long as it involves German components. Internationally, things get more complicated, but step by step...
Metric Grease Nipple Threads
On grease nipples, you can find mainly two types of metric threads – depending on whether it is a conical or cylindrical thread.
The conical metric thread on the grease nipple
This is usually a grease nipple with a conical metric thread according to DIN 158. This thread has a flank angle of 60° and a cone of 1:16. The thread designation is derived from the letter M, nominal diameter and pitch, and the addition of "keg." for example, M 6x1.0 keg.
Grease nipple with metric fine thread
If the grease nipple has a cylindrical thread, it is usually a metric fine thread MF. This also has a flank angle of 60°, and the thread designation includes nominal diameter and pitch.
Imperial Grease Nipple Threads
For imperial threads on grease nipples, you will encounter thread types that you may already know as pipe threads.
The cylindrical pipe thread BSP on the grease nipple
The thread BSP on the grease nipple is the cylindrical Whitworth pipe thread, which is also known as British Standard Pipe Parallel (BSPP) in its country of origin, the UK. The thread designation consists of the letter BSP and the nominal diameter in inches.
Grease nipple with conical pipe thread R
Here, it is another well-known Whitworth conical pipe thread, British Standard Pipe Tapered (BSPT). You can recognize it by the abbreviation R followed by the outside diameter in inches.
International Grease Nipple Threads: Threads from other countries you should know
In addition to the four types of threads on grease nipples that you will encounter most frequently in Germany, there are also some international variations. Knowing these is especially important when working with components from the USA or other countries. American Unified National Fine (UNF) and Unified National Extra Fine (UNEF) fine threads are often present, but you may also discover American pipe threads National Pipe Taper Fuel (NPTF) and Pipe Thread Fuel (PTF), with 1/8" NPT being the most common thread size on grease nipples. Less known but also frequently encountered is the SAE‑LT thread of the Society of Automotive Engineers.
Determine which Grease Nipple Thread Tap you need
To find out which of the listed threads your grease nipple has and which grease nipple thread tap you need, you have several options. You can determine your grease nipple thread in three steps:
- Determine whether it's conical or cylindrical.
- Identify the pitch by comparing with a template or a screw with a known pitch.
- Measure the outside diameter.
These three aspects should lead you to the correct thread.
If you frequently work with grease nipples, an identification aid could also be useful. This is a rectangular disc with threads of all common standards and sizes, into which you can screw the grease nipple for a test. You can make it even easier by using self-tapping grease nipples that create the thread when screwed in! That will definitely fit. In case of doubt, we are here for you as a thread tap manufacturer and expert for questions and advice on determining the thread of grease nipples.
You can find a guaranteed matching thread tap for every grease nipple at the BAER Online Shop. Take a look!