In an era where energy efficiency isn’t just desirable but essential, the components within electrical equipment face increasing scrutiny. Every watt lost to heat or inefficiency represents both environmental impact and operational cost. For manufacturers of motors, transformers, and generators, electrical laminations offer a proven solution to one of the most persistent challenges in electrical engineering: minimising energy losses whilst maximising performance.
At Cotmor Tool and Presswork, we’ve spent over 70 years refining our electrical lamination manufacturing capabilities, supporting clients across diverse sectors with precision-crafted components that enhance efficiency, reliability, and longevity in critical electrical equipment.
Electrical laminations are thin sheets of specialised metal—typically silicon steel or similar alloys—that are stacked together to form the cores of transformers, electric motors, and generators. But why use multiple thin sheets rather than a single solid core? The answer lies in a phenomenon called eddy currents.
When alternating magnetic fields pass through conductive materials, they induce circular electrical currents within the material itself. These eddy currents don’t contribute to the device’s intended function; instead, they generate heat and waste energy. In solid metal cores, these losses can be substantial, reducing efficiency and creating thermal management challenges.
By dividing the core into thin, electrically insulated layers, electrical laminations dramatically restrict the path available for eddy currents to flow. Each lamination is coated with an insulating varnish or oxide layer, preventing current flow between layers whilst allowing magnetic flux to pass through effectively. The result is significantly reduced energy losses, cooler operation, and improved overall efficiency.
Creating effective electrical laminations requires precision at every stage. The process begins with high-grade electrical steel sheets specifically formulated for optimal magnetic properties and minimal energy losses. These materials must meet stringent standards for composition, grain orientation, and surface finish.
Our manufacturing process includes:
Precision Stamping: Using carefully designed dies, we stamp lamination shapes with exceptional accuracy. Dimensional precision is crucial—variations of even fractions of a millimetre can affect stacking efficiency and magnetic performance.
Insulation Coating: Each lamination receives a thin coating of insulating material. This coating must be durable enough to withstand handling and stacking whilst remaining thin enough not to significantly increase the overall core dimensions.
Quality Verification: Throughout production, we verify critical characteristics including dimensional accuracy, coating integrity, and material properties. Our ISO 9001:2015 accreditation ensures consistent processes and thorough documentation.
Stacking and Assembly: For complete core assemblies, laminations are precisely stacked and securely bonded, maintaining alignment whilst ensuring the insulation between layers remains intact.
Enhanced Energy Efficiency
Reducing eddy current losses directly translates to improved energy efficiency. For equipment operating continuously or under heavy loads, even modest percentage improvements in efficiency generate substantial energy savings over the equipment’s lifetime. In industrial settings, these savings can significantly impact operational costs.
Reduced Heat Generation
Lower energy losses mean less heat production. This reduces cooling requirements, extends component life, and improves reliability—particularly important in enclosed or thermally challenging environments. Equipment that runs cooler experiences less thermal stress and requires less maintenance.
Improved Magnetic Performance
High-quality electrical steel laminations enhance the magnetic properties of cores, improving the power density and performance characteristics of motors and transformers. This allows engineers to design more compact, powerful equipment or achieve better performance from existing designs.
Extended Equipment Lifespan
Cooler operation and reduced electrical stress contribute to longer equipment life. The initial investment in quality laminations pays dividends through reduced maintenance, fewer failures, and extended replacement intervals.
Regulatory Compliance
Modern energy efficiency regulations increasingly mandate higher performance standards for electrical equipment. Quality electrical laminations help manufacturers meet or exceed these requirements, ensuring their products remain competitive and compliant in regulated markets.
Transformer Manufacturers
From small distribution transformers to large power transformers, laminations are essential for efficient energy conversion and distribution. Whether you’re producing units for utilities, industrial facilities, or specialised applications, precision laminations ensure optimal performance.
Motor Manufacturers
Electric motors power countless applications—from industrial machinery and HVAC systems to automotive applications and home appliances. Quality laminations improve motor efficiency, reduce operating costs, and help manufacturers meet increasingly stringent energy standards.
Generator Manufacturers
Generators for power generation, backup systems, and portable applications benefit from laminations that maximise energy output whilst minimising losses. This is particularly crucial in renewable energy applications where every watt counts.
Renewable Energy Sector
Wind turbines, solar power systems, and other renewable technologies rely on highly efficient electrical components. Our laminations support the renewable energy transition by helping maximise the output from sustainable sources.
Industrial Automation and Robotics
Precision motors in automated systems and robotics require consistent, reliable performance. Electrical laminations contribute to the smooth, efficient operation these applications demand.
Research and Development
Whether you’re developing next-generation motor designs or testing innovative transformer configurations, we can support prototype development with small-batch production and rapid turnaround times.
Decades of Specialised Experience
Our seven-decade history includes extensive work in electrical laminations for diverse applications. This experience informs our understanding of critical tolerances, material selection, and quality requirements specific to electrical applications.
Comprehensive In-House Capabilities
From initial tool design through final production, we handle electrical lamination manufacturing entirely within our West Midlands facility. This integrated approach ensures consistent quality, rapid problem resolution, and complete control over the manufacturing process.
Material Expertise
We work with various grades of electrical steel and specialised alloys, helping you select the optimal material for your specific application requirements. Our supplier relationships ensure access to high-quality materials that meet international standards.
Flexible Production Volumes
Whether you need prototype quantities for R&D work or high-volume production runs for established products, we can accommodate your requirements. Our scalable approach means you work with the same team and quality standards regardless of order size.
Quality Assurance
Our ISO 9001:2015 accreditation reflects our commitment to quality management throughout all processes. Regular sampling, dimensional verification, and coating integrity checks ensure every lamination meets your specifications.
Design Support
Our engineering team can review your core designs and offer recommendations for manufacturability, material selection, and cost optimisation. This collaborative approach often identifies opportunities to improve performance or reduce costs before tooling production begins.
Every electrical application presents unique challenges and requirements. Standard laminations may not always provide the optimal solution for specialised equipment or innovative designs. Our custom manufacturing capabilities allow us to develop lamination profiles tailored to your specific needs, whether that involves unusual geometries, specialised materials, or unique coating requirements.
We’ve supported clients developing everything from compact, high-efficiency motors for electric vehicles to large industrial transformers for power distribution. Whatever your application, we’re equipped to develop solutions that meet your performance requirements whilst maintaining manufacturing efficiency.
At Cotmor, we view our client relationships as partnerships rather than transactions. Our family-run business model ensures you receive personal attention and responsive communication throughout your project. We’re genuinely invested in your success because our reputation depends on delivering components that perform reliably in demanding applications.
Many of our electrical lamination clients have worked with us for years, trusting us with both ongoing production and new development projects. This loyalty reflects our consistent quality, competitive pricing, and commitment to supporting our clients’ evolving needs.
Ready to enhance your electrical equipment’s efficiency with precision laminations? Contact Cotmor Tool and Presswork on 01384 482 993 or visit www.cotmor.co.uk to discuss your electrical lamination requirements with our experienced team.
