What is static electricity
Static means not moving. Static electricity is an electrical charge that doesn't move. All materials are made up of atoms. An atom is the smallest particle of a material that still contains the properties of the material. Each atom consists of a positively charged nucleus around which one or more negative electrons move. In an idle state, the positive charge of the nucleus is equal to the sum of the negative charge of the electrons moving around the same nucleus. Therefore the charge is neutral (see figure 1). If the nucleus loses or gains electrons, an imbalance is caused. An atom that has lost one or more electrons then has a positive charge, and an atom that has gained one or more electrons has a negative charge and is called an ion (see figure 2). There are only two types of charge: positive and negative. Atoms with the same type of charge repel one another, while those with the opposite type of charge attract one another.
How is static electricity generated
Static electricity is a surface phenomenon and is generated when two or more surfaces come into contact with one another and are separated again. This causes a sort of splitting, or a transfer of negative electrons from one atom to the other. The level of charge, (the field strength) is dependent on a number of factors: the material and its physical and electrical properties, temperature, humidity, pressure and speed of separation. The greater the pressure or the speed of separation, the greater the charge (see figure 3).
Conductive and non-conductive materials (insulators)
Materials can be divided into two basic groups: conductors and insulators. In a conductor, the electrons can move around freely. In principle, a conductor that is arranged in an insulated way can take on a static charge. This charge can easily be eliminated by connecting the conductor to earth (see figure 5). Non-conductive material can retain static charge for a long time, even having opposite polarities in different places. The electrons cannot move around freely. This explains why materials are attracted in some zones and repelled in others. Connecting to earth does not work because the material has non-conductive properties (see figure 6). Only active ionisation offers a solution to this.
What is the effect
In production processes, static charge can often be a severe disruption, as it means that materials get stuck to machine parts or to each other. Operators do not like getting electric shocks. The dust in the surrounding area is attracted by the electric charge. In explosionhazardous zones, static charge can cause a spark, which in turn can cause a fire or even an explosion.
How can static electricity be controlled
Neutralising the static charge of nonconductors is carried out by means of active ionisation. Simco is world-renowned as a producer of ionisation equipment. At the high-voltage points of this equipment, air molecules are split up into positive and negative ions. The static charge on the product attracts ions of the opposite polarity, thus neutralising the material. Simco has a wide range of equipment to choose from depending on which type is the most suitable for certain production processes or applications. However, static electricity can also be useful. Using high voltage, materials can be given a static charge so that they will stick to each other temporarily, thus simplifying production processes.
To put it simply, Simco makes equipment for measuring and controlling static electricity. Through a unique concept, the IQ Easy Platform, up to thirty ionisation and charging devices can be connected in a network and allows full control over all parameters. All devices communicate with each other to optimize efficiency.
How Static Charges Hinder Manufacturing Processes:
- Converting: static charge buildup results in dust and dirt attraction to web. Material is rejected.
- Packaging: static charge buildup attracts contaminants so that clear labels do not stick. Production decreases.
- Plastics: injection molded parts attract contaminants and shock personnel during processing due to static charges. Efficiency declines.
- Textiles: static charges cause threads to bind and break in creels and warpers. Machine downtime.
- Nonwovens: trim collection systems clog due to increasing static charge buildup on materials in pneumatic conveyors. Increased maintenance.
- Printing: sheet-fed press feed and delivery is troublesome due to static. Untimely delivery.
- Graphic Arts: static charge buildup while processing film results in costly retouching or remakes. Dissatisfied customers.
- Medical Device Manufacturing: static charges attract contaminants to small plastic parts prior to packaging. Decreased quality.
- Electronics: destructive electrostatic discharge (ESD) causes latent damage to board assembly. Field failure.
How SIMCO Static Control Equipment Enhances Manufacturing Processes
- Converting: neutralized material remains free of dust and dirt during rewind. Decreased rejects.
- Packaging: elimination of static charges on labels and/or bottles allows for successful application of product labels. Increased production.
- Plastics: following neutralization, injection molded parts do not stick together while being conveyed. Line efficiency increases.
- Textiles: threads run smoothly through creels and warpers run at optimum speeds without undue maintenance. No unnecessary downtime.
- NonWovens: trim collection system runs without interruption due to static elimination of charges prior to entering cyclone. Increased production.
- Printing: sheet-fed delivery is clean and stacked accurately-ready for bindery without adjustment. On time delivery.
- Graphic Arts: processed film remains dust free, eliminating the need for remakes. Satisfied customers.
- Medical Device Manufacturing: contaminant free packaging of small plastic parts due to elimination of static charges on parts and packaging materials. Increased quality.
- Electronics and Semiconductor: protection from ESD during assembly work ensures achievement of quality assurance standards. Reduced product failure.