How balls of ball point pen is manufactured?


Most of the times steel wires are used as raw material which is fed to forming machine which has spherical shaped dies.

Step followed for manufacturing
1. Forming by Heading
2. Flashing
3. Heat treatment
4. Grinding
5. Lapping
6. Washing
7.Precision and NDT testing

This wire is fed from a roll into a machine that cuts off a short piece, and then smashes both ends in toward the middle. This process is called cold heading.

Process is explained through following figures




         The steel wire is fed into spherical shaped dies


                            And a spherical ball is produced


Flashing is a process of removing uneven burrs and surfaces

 Heat treatment is done to increase the hardness of the steel balls.
Precision grinding is done to improve surface finish further
Then lapping is performed to produce mirror like surface finish

In the same way different sizes of balls can be manufactured for different uses.
Close view of steel ball of ball point pen.

Text format of manufacturing process of steel balls

Cold heading: Cut the tested coil wire into short lengths and then compress each piece into ball shapes with heading machine. After this precess, each ball still has a protruding band (Burr) around the middle. It need to be removed in the next process.

Deflashing: Remove the burrs and produce a spherical shape with deflashing machine. In this process, the noise is very loud. It is because the balls are being ground inside grooved disks at a tremendously high pressure.

Heat treatment: Heat the balls with high temperature and then quench and temper them to give them sufficient strength and durability. Quenching means cooling the balls quickly from a high temperature. It will change the structure of the steel to make it harder but the balls are still brittle. Then the balls need to be heated again to a high temperature for further strengthening which is called tempering.

Hard grinding: This process adjusts the dimensional precision and finishes the balls to the stipulated dimensional difference with grindstone disks. According to the requirements, it could be separated into first grinding and second grinding.

Lapping: This process is the last process of manufacture. In our company, there are first lapping and second lapping to ensure the precision of steel balls. All the requirements include ball diameter, roughness, variation ball diameter, cariation of ball lot diameter, deviation from spherical from & vibration value etc. must be strictly inspected.

Visual Inspection: All the completed steel balls will be visually inspected by our inspector to make sure no surface defects.

There are also many inspections in or after the production processes, like hardness, surface roughness, deviation from spherical form etc.

Comments

  1. Unknown8 June 2019 at 01:47

    Good work.
    And maybe you can use gifs for better sharing.

    ReplyDelete
  2. Anonymous30 August 2020 at 05:35

    Very educational, thank you

    ReplyDelete
  3. RobertNelson9 February 2021 at 07:50

    Thank you for posting such a great blog. I found your website perfect for my needs. Read About Breast Shaped Stress Balls

    ReplyDelete

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