Local reinforcement of insulated mesh for transposed conductors
Category:
Product Description
To enhance the local electrical insulation of the windings at specific locations—such as the top, bottom, and sides of the interposed lead wires—insulating paper is inserted; heat dissipation is then accomplished through the remaining surfaces where no insulating paper is applied.
This product can reduce conductor current density, decrease the dimensions of conductors and spacers, and improve the spatial utilization of the windings, thereby facilitating a reduction in transformer size and lowering manufacturing costs. Moreover, the use of mesh straps for binding significantly reduces thermal resistance and enhances the winding’s heat dissipation performance.
This product can be widely used in the low-voltage windings of AC transformers across various voltage levels.
Main technical specifications:
Number of core conductors: 5 to 87.
Enamelled flat wire specifications (mm): side a: 0.90–3.50; side b: 3.35–14.00. For transposed conductors with more than 55 strands, to better ensure the winding processability of the conductor, it is recommended that side a be 1.30–1.70 mm and side b be 5.3–7.5 mm, and that semi-rigid conductors be used.
Enamel-coated flat wire width-to-thickness ratio: b/a ≤ 7.
Core dimensions of the transposed conductor (mm): W1 ≤ 28; H1 ≤ 90.
Aspect ratio of the transposed conductors: ≤6.
Enamel coating thickness for acetal enamel wire (mm): typically 0.09–0.13. (Customization available upon customer request.)
Self-bonding enameled wire enamel film thickness (mm): as per customer requirements. When no specific requirement is provided by the customer, the acetal layer is typically 0.08–0.10 mm, and the self-bonding layer is typically 0.03–0.05 mm.
Paper wrapping methods: overlapping wrap, gap wrap, interlocking wrap, etc., subject to mutual agreement.
Webbing thickness (mm): 0.28; 0.40; (custom processing available upon customer request)
Transposition pitch (mm): The transposition pitch S shall not exceed π/n times the minimum coil diameter Dmin, i.e., S ≤ π/n × Dmin. Typically, 8b ≤ S ≤ 18b; in special cases, the parties involved may negotiate otherwise, and the transposition pitch may be less than 8b.
Bonding strength (120°C for 24 hours, MPa): ≥ 5.
Resistivity ρ20 (Ω·mm²/m): ≤0.017241.
Specified non-proportional extension strength Rp0.2 (MPa): 80–280. (Wire with a strength exceeding 100 MPa is classified as semi-hard wire.)
Paper tray positions: top, bottom, and side.
Any requirements beyond the above may be determined through negotiation between the supplier and the buyer.
Previous Page
Next page
Product Advantages
Leveraging more than two decades of technological expertise and industry-leading manufacturing capabilities, the company has developed core product advantages characterized by high electrical conductivity, low loss, corona resistance, and exceptional reliability. By employing high-purity oxygen-free copper and state-of-the-art insulation processes, the products deliver outstanding mechanical and electrical performance, meeting the stringent requirements of high-voltage transmission and transformation applications as well as emerging sectors such as new-energy vehicles. This comprehensive approach enhances equipment operational efficiency, extends service life, reduces overall energy consumption, and provides customers with a stable, efficient, and secure one-stop electromagnetic wire solution.
Higher electrical conductivity
● Excellent electrical conductivity and low copper losses, enhancing motor efficiency and service life.
● Hongyuan Company Standard: Copper purity ≥ 99.99%, resistivity at 20°C ≤ 0.01710 Ω·mm²/m.
Control measures: High-purity Class A copper plates are self-cast to ensure excellent electrical performance.
Lower oxygen content
● Low oxygen content ensures high welding quality, thereby extending the service life of the motor.
● Hongyuan Company Standard: Oxygen content < 8 ppm.
Control measures: High-quality Grade A copper plates are self-drawn and cast, and process technical requirements are established for the charging frequency of electrolytic copper plates, smelting temperature, cooling rate, and protective measures during the melting process in the upward-drawing production process, to ensure that the copper rods have high purity and low oxygen content.
Smaller fillet radius
● A smaller fillet radius results in a higher packing density and higher motor efficiency.
● Hongyuan Company Standard: Minimum corner radius of 0.30 mm.
Control measures: Molds are manufactured using precision CNC technology and inspected with a projector, ensuring that the round-corner radius deviation is within ±10%.
Smaller coating film eccentricity
● The smaller the eccentricity, the more uniform the coating film and the better its electrical properties, such as corona resistance.
● Hongyuan Company Standard: Coating film eccentricity: maximum thickness/minimum thickness ≤ 1.3.
Control measures: Maintain optimal baking temperature, varnish bath temperature, and viscosity; conduct projection inspection on both bare-wire molds and coating molds to ensure that the fillet radii are properly matched, thereby guaranteeing uniform coating.
Better film flexibility and adhesion
● Excellent flexibility and adhesion to prevent cracking of the coating at the ends during bending.
● Hongyuan Company Standard:
Film flexibility: The coating film shall not crack when rolled up to twice its original thickness and twice its original width.
Coating adhesion: After cutting and stretching by 15%, the distance at which the coating loses adhesion shall be no greater than 0.5 times the conductor width.
Control measures: Employ the optimal painting process and precisely control the thickness of each paint layer.
Higher partial discharge inception voltage (PDIV)
● The higher the PDIV value of the winding, the longer the insulation system’s service life under aging conditions.
● Hongyuan Company Standard: Single-coat film thickness of 0.13 mm, PDIV (Vp) ≥ 1900 V.
Control measures: use PI varnish with a low dielectric constant, increase the varnish film thickness, and enhance the degree of varnish curing.
Higher corona resistance
● Enhancing corona resistance can reduce partial-discharge-induced coating degradation, thereby extending the service life of electric motors.
● Hongyuan Company Standard: Single-coat film thickness of 0.12 mm, corona resistance life ≥ 500 hours.
Control measures: modify the properties of the insulating varnish, increase the coating thickness, reduce coating eccentricity, and enhance coating cure.
Get more product information
Contact us now for a free expert consultation!
Phone
Address
No. 12, Shenxi Third East Road, Shenyang Economic and Technological Development Zone, Shenyang, China
Follow us