Today, we are going to discuss the "Difference between knock pin (dowel pin) and parallel pin and how to use themHere is a note about "The
We have researched and summarized the differences between knock pins and parallel pins and how to use them. If you are looking for positioning pins in the future, please refer to this page.
Difference between knock pin (dowel pin) and parallel pin
Now, we will note the difference between knock pins and parallel pins.
(1) Features, Shapes and Tolerances of Dowel Pins (Dowel Pins)
A "knock pin" is a pin that is "knocked in.Dowel pins are generally referred to as knock pins.Dowel pins are specified in JISB1355 and JISB5062. Dowel pins are pins used for centering and positioning of equipment and are sometimes called "dowel pins.
JIS, but why there are two types of JIS can be broadly divided as follows.
- JISB1355: Dowel pins = No hardness specified
- JISB5062: Dowel pins for molds = hardness specified
Thus, a positive tolerance is applied to the shaft diameter. You can see why they are called "hammered (press-fitted) = knock pins. Also, the greatest feature isThe knock pin is suitable for places that are repeatedly removed and attached because the pin is hard according to the hardness specification.This will be the case.
(2) Parallel pin characteristics, shape, and tolerances
In contrast, parallel pins are,Both positive and negative tolerances present and no hardness specifiedwill be.
Since hardness depends on the material, it is good to recognize that it is rather unsuitable for places where repetitive positioning is required.
Difference between knock pin and parallel pin and how to use them
To summarize the information so far, the difference between a knock pin (dowel pin) and a parallel pin is
- Knock pins are pins that have a positive tolerance hardening treatment and are classified with or without a tap.
- Parallel pins have both positive and negative tolerances and are not hardened (tapped pins are classified with or without a tap, but tapped pins are hardened)
This is how it works. In addition, a brief description of how to use it is as follows.
(1) The required pin diameter tolerance is determined by whether the pin is positioned by press fitting or rough positioning.
- Plus tolerance (knock pin type) for tight tolerances by press-fitting parts together
- Minus tolerance (parallel pin type) for easy attachment/detachment and rough decision making
(2) Do you want the hardness of that pin to be strong enough to withstand repetition?
- If you want to repeat the process, a knock pin with a hard surface is better.
- If you hit it and basically don't move it, you don't need hardness, so a parallel pin is fine.
If you are aware of just these two things, the selection process will be easier.
If someone asks, "What's the difference between knock pins and parallel pins?" If you ask, "What is the difference betweenAlthough knock pins and parallel pins are different in terms of JIS standards, there are many types of pins on the market. The important thing is to understand the purpose of the pin to be used and to select the pin based on the required function.and advise them to do so.
For more detailed information on how to use the system, please check this article.
⇒How to use knock pins and parallel pins and reference design methods such as hole tolerances
Download Excel table
Here you can download an Excel sheet that summarizes the information on knock pins and parallel pins. Please use it if you like.
That's it.