How Are Ballpoint Pens Made?
Overview of Ballpoint Pens
A ballpoint pen is a writing instrument that dispenses ink via a metallic sphere at the pen's tip. There are two main types of ballpoint pens: disposable and refillable. Disposable pens contain a fixed plastic ink cartridge and are discarded when the ink is used up. Refillable pens have a removable ink cartridge that can be replaced when empty. Disposable pens are made from plastic while refillable pens are made from either metal or plastic. Some ballpoint pens have a retractable tip that is attached to a spring, which can be retracted or deployed by a button at the top of the pen. Ballpoint pens are cheap and durable and are the writing instrument of choice in modern society.
Components of Ballpoint Pens
A variety of components are used to make ballpoint pens, including plastic, metal and chemicals. In most ballpoint pens, the writing sphere is made from brass, although you can also use steel or tungsten. In metal pens, the body, ink cartridge and spring are also made of brass or aluminum. Virtually all ballpoint pens contain a significant amount of plastic. Even the most expensive pens use plastic for the push button, ink cartridge, cap and tip. Ballpoint pen manufacturers use a variety of plastics, including high-density polyethylene, vinyl resins and thermosetting plastic, which remains rigid after being molded and cooled.
Manufacturing Process -- Ink
Ink is manufactured by combining a variety of chemicals, which are then mixed together and heated or cooled in order to facilitate the necessary chemical combinations. Workers follow strict formulas when producing ink, and most modern pen manufacturers use computerized controls to regulate the quantities of chemicals and the mixing process. A separate group of workers performs quality checks throughout the ink manufacturing process.
Manufacturing Process -- Metal
The metallic writing spheres for ballpoint pens are generally purchased from an outside supplier, such as a light metal manufacturing business. Pen manufacturers create the remaining components for metal pens using metal stamping and molding equipment. Small pieces of metal are fed into a molding machine, which liquefies the metal and pours it into a compression chamber. The compression chamber injects the liquefied metal into a die cast mold, which cools the metal and forms the various pen pieces. When the metal is cooled and hardened, any excess metal is scrapped of. The die cast opens and the pen component is removed. The components are then cleaned and machine-cut according to the specifications of the pen for which they will be used. The cut pieces are machine polished and cleaned again before being sent to assembly.
Manufacturing Process -- Plastic
The plastic components are manufactured by injection molding. In this process, plastic resin is placed in a hopper, which forces the resin through a heated compartment. The heat liquefies the resin, which is injected into a die cast mold, cooled and removed. Excess plastic is then scrapped away, and the pieces are polished, cleaned and sent to assembly.
Assembly
During the assembly process, the metallic writing sphere is first inserted into a cavity at the tip of the ink cartridge. The ink cartridge is then placed in an injector, which fills the cartridge with ink. For retractable pens, workers then attach a spring to the front of the cartridge to allow the tip to retract and deploy. The completed ink cartridge is then placed inside the body of the pen. Then the pen's cap and top are attached. Assembly is now complete, and the finished pens are cleaned, packaged and shipped.
