Coil winding is the process of wrapping wire, foil, bar, or hollow conductor into the shape of spiral wild, jumble, helical or custom form with copper or aluminum material. The shape and dimensions of a coil are designed to fulfill a particular purpose with certain parameters such as inductance, resistance, and the strength of the desired magnetic field, and coil winding technique is widely used for magnetic applications such as motors, transformers, and generators.
Description
Electromagnetic coils are used in applications where electric currents interact with magnetic fields, such as in inductors, electromagnets, transformers, and sensor coils. Either an electric current passes through the coil to generate a magnetic field, or conversely, an external time-varying magnetic field passes through the interior of the coil, generating a current in the conductor. An electromagnetic coil is produced by winding an electrical conductor such as copper wire, bar or hollow tube into the desired shape. According to the design and technological features, custom coil winding can be classified by shape like cylindrical, disk, continuous, twisted, and screw-type (helical) windings. The choice of winding type depends on the number of turns, size, cross-sectional shape and number of parallel wires, as well as cooling method, transformer power, coil material, insulation strength, inductance property, and space allowance. Fabmann provides custom coil winding service for electromagnets, and we are able to supply you custom electromagnets which are economical to build in low quantities for affordable prototyping & experimental applications. Our hollow conductor electromagnets offers the highest thermal conductance to deliver maximum heat dissipation, they are widely used for applications requiring high power (20 kGauss and greater).
What's the difference between coil and winding?
Coil and winding may sound similar, but they represent different concepts in electrical world. If winding is the housing for an electrical component, coil is designed to maximize the area of the magnetic field once the electrical current starts to flow through it.
Winding, winding process starts with the physical act of arranging the conductive wires into certain loops and turns to form the base of many electrical components, and this process begins with selecting the wire, choosing the shape, and carefully wrapping the wire to form the desired coil.
Coil, it is a series of conductive materials wrapped in a specific shape for unique electrical properties based on its construction, which makes it an essential component of many electrical devices. Coils are ideal for electric applications needing a strong, more focused electromagnetic field.
Winding is the act of wrapping a conductor to create a coil.
In short, winding focuses on the arrangement of the conductor, while a coil focuses on its electrical or magnetic function. A winding can be incomplete or ongoing, while a coil is the finished product of the winding process, a single or multiple turns of wire with specific electrical and magnetic properties.
What are the advantages of hollow conductor coil wound?
Custom Winding of Hollow Conductor
Hollow conductor is designed for flowing liquid coolant through the entire coil length, it allows greater winding heat transfer than any other construction method, enabling the highest field strengths with extremely low temperature rise meanwhile insulated hollow tubing carries coolant without impacting the magnetic field pattern. Therefore, the hollow conductor coil wound has following advantages:
√ Excellent for "brute strength" applications requiring high power (20kG and greater)
√ Coaxial coolant path in direct contact with entire coil length
√ Optimal thermal conductance delivers maximum heat dissipation
√ Great malleable characteristic for complex or unusual designs
√ Strong isolation of turns minimizing shorting, allowing low AC losses.
Due to above stated strength, Fabmann is able to fully explore hollow conductor's great flexibility and malleability to make custom electromagnets with wide range of shape options including racetrack, thin pancake, open yoke, and much more. We specialize in designing, building, and testing AC, DC, and pulsed electromagnets, and our engineers proactively working with our clients to initiate the design meanwhile our simulation engineers can further polish the design, and our coiling division can bring the design into reality. We specialize in both ferrous and non-ferrous electromagnets for applications such as beam focusing, bending, and kicking as well as force, flux uniformity, and levitation.
What are the advantages of wire coil wound?
Wire coil has very obvious advantages, and that's why they are widely used for many industries like electromagnets, motor & generator, transformer, inductor & capacitor, communication and heating. The advantages are:
√Economical to build in low quantities
√ Shortest first-unit delivery time
√ Built from standard materials, utilizing standard tooling
√ Enables affordable prototyping for experimental applications
√ Successfully serves a broad range of applications
√ Flexible options for heat dissipation
√ Square or rectangular wire options enable reduced power requirements
What are the advantages of foil wound?
Winding of Copper Foil
Foil wound offers a unique alternative to traditional wire-wound electromagnets, with distinct advantages below:
√ High winding precision
√ Highest field accuracy with lowest transverse field
√ Great fill and packing factor, yielding highest field to weight ratio
√ Economically viable for building in larger quantities
√ Most compact weight and space-saving configuration
√ Most flexible configuration in shape and size
√ Customable design for slots and holes
√ Vastly improved heat dissipation
Due to above benefits, foil wound coils are widely use for high-power electromagnets, pulse magnets as well as compact electromagnets. Since foil wound has higher current density, which can lead to increased skin effect, resulting in reducing efficiency. Meanwhile winding foil requires specialized equipment and techniques, making it more complex than wire winding. Foil wound electromagnets offer advantages in terms of current density, cooling, and compactness, making them suitable for high-power and space-constrained applications. However, their lower mechanical strength and higher skin effect require careful design considerations. When selecting between wire and foil windings, the specific application requirements and constraints should be carefully evaluated to determine the most appropriate choice. If you have any further questions or require more specific information about foil wound electromagnets, please provide details about your application, and Fabmann electromagnet engineers will be able to assist you.
What are the winding solutions for custom coil?
High precision coils can minimize the materials and volume required for a specific application, and the ratio of the area of electrical conductors, to the provided winding space is called "fill factor". Round wires always have some gap, and wires also have some space required for insulation between turns and between layers, the fill factor is always smaller than one. To achieve higher fill factors, rectangular, square or flat wire are often chosen. Coil winding involves wrapping a wire around a cylindrical object in a spiral-like shape to produce a standalone coil or a coil on a toroid, bobbin, or other type of center support. The coil may be made of one or more layers of wires depending on its intended application, and coil winding is a delicate basic techniques employed to achieve high quality winding:
√ Shedder winding, also called flyer winding, this solution attaches wires to a rotating part called a flyer, and clips hold the wire in place as it spins around the coil, and it is not suitable for good wire packing requirement.
√ Needle winding, the winding solution uses a needle with a special nozzle to guide wires up and down as they are wound into coils. This type of winding is similar to a sewing machine, whereby the wire goes through a hollow needle that moves around the pole circumference over and over again. As the pole becomes covered, it will move up and down in neat rows, before moving onto the next pole to repeat the process. This technique can be used for both direct and indirect winding but is not typically used for indirect winding because it is a slower process.
√ This technique is used in many applications as it is a simple and more cost-effective method, and automation is very easy.
√ Linear winding, it involves wrapping wire around a rotating coil body or device, and the wire is then wound in layers to create the coil with even spreading. It shares the similarity to needle winding, is used to wind onto the cartridges of bobbins at extremely fast speed.
√ Toroidal winding, this process creates coils in the shape of a circular ring called a toroid.
√ Spiral winding, this winding solution involves wrapping wire around a core in a continuous spiral pattern with each turn of wire placed directly above the previous one, and this technique is often used in applications where compact size and efficient use of space are important.
√ Parallel coil winding, it involves winding multiple wires side by side in parallel, typically with the same number of turns. This technique is chosen when increased current-carrying capacity or lower resistance is required.
√ Orthocyclic winding, it is a specialized technique that creates layers of wire wound at various angles to the coil axis, and this winding solution optimizes coil properties for certain electromagnetic devices which require specific magnetic field patterns. This type of winding structure creates an optimal fill factor above 90% for round wires, and the windings of the upper layer need to be placed into the grooves provided by the lower layer.
√ Wet winding, it involves coating the wire with liquid adhesive or resin before winding onto the core, providing bonding and insulation for improved coil integrity and longevity, and boosting reliability and performance.
√ Thermal winding, also called hot air winding, it heats the wire during winding, enhancing flexibility and adherence to complex core shapes. This technique ensures reduced residual stresses with smoother winding for better conformity to core contours, and it can improve coil stability and durability for applications demanding precise coil formation and optimal electrical performance.
Coil winding requires specialized tools and great expertise to achieve precision, consistency, and efficiency, and the winding techniques are widely used for dipole, quadruple, hexapole, rectifier, bending and solenoid electromagnets.
Fabmann specializes in designing, building, and testing AC, DC, and pulsed electromagnets as well as ferrous and non-ferrous electromagnets for applications such as beam focusing, bending, and kicking as well as force, flux uniformity, and levitation.
Withstand Voltage Test to Ground
What are the test requirements for coil winding?
Coil windings are crucial components in various electronic devices and systems, ranging from transformers and motors to inductors and sensors. Ensuring the quality and reliability of coil windings requires comprehensive testing to verify their electrical, mechanical, and functional characteristics. Below are the key test requirements:
1. Electrical Test
√ Insulation resistance test, it measures the resistance between the conductor and the core to ensure proper insulation and prevent electrical shorts.
√ High-Voltage test, also called hipot test, it applies a high voltage to the coil winding to test its dielectric strength and identify any insulation weaknesses.
√ Resistance measurement, this test verifies its conductivity and identify any breaks or loose connections.
√ Inductance test, it measures the inductance of the coil winding to verify its ability to store magnetic energy and ensure it meets design specifications.
√ Capacitance test, it measures the capacitance of the coil winding running at high frequencies.
√ Leakage inductance test, it measures the inductance between adjacent turns in the coil winding, which can cause energy losses and reduce efficiency.
√ Q-factor measurement, it measures the quality factor of the coil winding, which indicates its efficiency and losses at a specific frequency.
2. Mechanical Tests
√ Tensile strength test, it measures the strength of the coil winding to withstand pulling forces without breaking.
√ Vibration test, it tests the coil winding's ability to withstand vibrations and shocks without degradation in performance or structural integrity.
√ Temperature test, it measures the temperature rise of the coil winding under operating conditions to ensure it remains within safe limits.
√ Life cycle test, it simulates repeated operation of the coil winding to assess its durability and identify any potential wear or fatigue issues.
3. Functional Tests:
√ Frequency response test, it measures the impedance or gain of the coil winding over a range of frequencies to ensure it meets design specifications.
√ Resonance frequency test, it checks the resonant frequency of the coil winding, which is important for its operation in tuned circuits.
√ Harmonic distortion test, it measures the amount of harmonic distortion generated by the coil winding, which can affect signal quality.
√ Performance test, it verifies the coil winding's ability to perform its intended function, such as filtering a signal, generating an oscillating magnetic field, or storing energy.
4. Magnetic Field Test
5. Visual inspection, it is conducted for spotting any physical defects, such as loose wires, broken connections, or damaged insulation.
Fabmann performs thorough testing for ensuring the quality, reliability, and performance of coil windings, and we production and quality engineers are working around the clock to ensure that coil windings meet your desired standards and function.