Good quality winding wires exhibit good mechanical properties. And the adhesion strength of enamel to the base copper or aluminium wire is quite critical in that matter. Let us see why.
If the winding wire is of poor quality, the enamel can peel off from the enamelled copper wire under harsh mechanical conditions. It may happen during production while stretching, at bends or if following a high-speed winding process.
As a manufacturer, this can cause significant wastage of time and resources for you, affecting your operating margins.
Not just during production, but it could happen at any time during the lifecycle of the product. If the enamel peels off from the copper wire while the equipment is in operation, it can be a nightmare. It can cause short circuits, insulation breakdown and premature failure of the appliance itself.
Such incidents can affect your brand perception and customer loyalty. The best way to avoid such losses is to ensure that the enamel sticks to the conductor well. In other words, opt for winding wire with good enamel adhesion strength.
What determines the enamel adhesion Strength in Winding Wires?
To understand that, let us see how enamel is attached to the wire.
During enamelled wire manufacturing, the bare copper or aluminium wire is passed through an enamel bath for uniform coating. (This enamel bath is basically a resin and solvent mixture.)
The enamel-coated wire is then cured at a high temperature for the enamel to stick to the base conductor well. Both enamelling and curing processes are repeated multiple times to get the required insulation strength.
As you can see here, the quality of the enamelling and curing process is crucial in obtaining good adhesive strength of enamel on the copper or aluminium wire.
So, What affects the adhesion strength of enamel in Winding Wires?
The quality of raw materials as well as the way the process is carried out decides the adhesion strength of enameled wires.
Quality of Enamel – Here the quality of the enamel is critical as impurities in the enamel can lead to insulation not sticking well to the enamelled wires.
Viscosity of Enamel Solution – If the viscosity of the enamel solution is not within range, it will result in non-uniform enamel coating, as it affects the absorption and drying of enamel.
These could lead to enamel peeling off from the conductor.
Curing Temperature – The curing process removes the residual solvent particles from the enamel. The temperature of curing is critical as low-temperature results in improper removal of solvent particles, affecting the adhesion of enamel to the wire. On the other hand, higher temperature during curing will make the enamel coating hard and brittle leading to crack formation.
Also, note that the purity of copper or aluminium and the presence of any oxidization layer on them also affect the adhesion strength of enamel on the copper. To prevent oxidation, it is ideal to carry out the curing process under a protective environment.
In a nutshell, the adhesion strength of enamel on winding wires is highly influenced by the quality of the manufacturing process.
Quality of Manufacturing of Winding Wires at Geekay
At Geekay, our experience in manufacturing winding wires guides us to follow the best practices required for your specific application needs.
We source our copper and enamel (Elantas, Fupao) from the best vendors in the world. We use best-in-class machinery and technology for winding wire manufacturing. [Read More – How a high-quality winding wire is made?]
Also, we have quality controls in place to monitor the entire process. We run multiple quality tests like the Peel Test, Jerk Test and Flexibility Test to ensure that the winding wires that we hand over to our clients have good enamel adhesion.
These tests are effective ways to evaluate the adhesion strength between the insulation material and the copper conductor. They simulate the mechanical stress applied on winding wires during their usage on a sample wire.
It helps identify any potential enamel adhesion strength issues that might arise during wire production or usage. Here is how –
A jerk test determines the adhesion strength of enamel by introducing sudden mechanical force. A large force is applied on a sample wire under tension, resulting in its breaking. The broken wire is inspected for insulation damage and roughness throughout. Any roughness or insulation breakage indicates poor enamel adhesion strength.
The flexibility test checks for enamel adhesion strength by doing tight winding of sample enamelled wire. The frequent stretching and bending of enamelled wires during the testing process introduce severe mechanical stress to the insulation layer. The tightly wound coil is examined thoroughly under a magnifying lens for any deformities in insulation. The presence of cracks or breaks in insulation indicates poor enamel adhesion strength in the magnet wire.
In the Peel test, scratches are introduced to the sample wire using sharp instruments. The wire is then put under tension and mechanically twisted heavily to see how long it takes for the enamel to peel off. If the enamel peels off in a short time, it indicates poor enamel adhesion.
Conducting regular peel, flexibility and jerk tests during the production process, or before using copper winding wires in various applications, helps prevent potential insulation failures and ensures reliable performance.
A good approach is to source your enamelled winding wires from suppliers stringent on high-quality parameters. Thus, you can be assured of the quality of the insulation’s adhesion strength on the wire and avoid production delays.
Geekay As a High Quality Super Enameled Winding Wire Supplier
Geekay or GK Winding is an established winding wire manufacturer since 1975. We keep innovating to meet the market demands and this has carved us as a versatile enamelled wire manufacturer focused on quality. We follow strict quality controls to deliver the winding wires exactly as per your requirements.
Contact us with your requirements for a sample to experience the quality advantage.