We have shared full knowledge about GPO-3 insulation board in previous articles from YILONG. This article will focus on a widely concerned topic: simple identification methods to distinguish qualified finished GPO-3 insulation boards from inferior ones. Let’s take a closer look.

How to identify the defective GPO-3 Insulation Boards?
Conduct Open Flame Test with Matches
Smoke generation marks inferior products Qualified GPO-3 insulation board features excellent bonding performance and eco-friendly raw materials, so no smoke will be released during combustion. By contrast, inferior boards will produce thick smoke when ignited.
Release of toxic pungent fumes Inferior products rely on low-quality flame retardants to achieve flame resistance, which will emit irritating toxic gas while burning. As the flame retardant volatilizes gradually, the overall performance of the board declines sharply. Such inferior boards are not suitable for environments with human exposure or continuous high temperature conditions.
Delamination after burning indicates counterfeit products The mechanical tensile strength of standard GPO-3 comes from its internal uniform glass fiber mat structure. No internal delamination will occur even after high-temperature carbonization. If obvious delamination appears during combustion, the product is counterfeit and substandard.
YILONG strictly implements full inspection standards for all GPO-3 Insulation Board finished goods to guarantee stable arc resistance, flame retardancy and long service life. Should you need free samples, technical test reports or customized processing services, kindly get in touch with our sales team:
Email: yilong@yilonginsulation.com
Website: www.yilonginsulation.com
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With balanced and comprehensive performance, Mica Board has broken the restrictions of single-industry application and been deeply applied in household appliances, traditional industry, power and electrical engineering, high-end new energy manufacturing and other fields, making it a universal all-around safety substrate.
We have shared full knowledge about GPO-3 insulation board in previous articles from YILONG. This article will focus on a widely concerned topic: simple identification methods to distinguish qualified finished GPO-3 insulation boards from inferior ones. Let’s take a closer look.
GPO-3 Insulation Sheet is a rigid sheet insulating material manufactured by impregnating non-alkali glass fiber mat with unsaturated polyester resin paste together with corresponding additives, followed by hot pressing. It refers to unsaturated polyester glass fiber mat sheet material for mechanical and electrical purposes. It delivers excellent electrical properties under high humidity, favorable mechanical performance at medium temperatures, inherent flame retardancy, as well as outstanding arc resistance and tracking resistance.
FR4 Sheet, also known as epoxy fiberglass sheet or flame retardant insulation board, is fabricated by impregnating fiberglass woven cloth with flame-retardant epoxy resin and hot-pressed under high temperature and pressure. It is widely utilized in high-end precision equipment that demands high safety and reliability standards.
FR4 fiberglass sheet is an insulation plate formed by hot pressing after impregnating woven fiberglass cloth with epoxy resin. It boasts excellent insulation performance, high mechanical strength and great temperature resistance, along with antistatic and flame-retardant features. Thanks to its comprehensive properties, it maintains stable dielectric performance in both dry and humid environments, making it one of the indispensable materials for photovoltaic power generation equipment.
Epoxy Glass Sheet boasts outstanding comprehensive performance, featuring high temperature resistance, corrosion resistance, high mechanical strength, superior machinability, low water absorption, reliable insulation and excellent electrical properties. There are various types of Epoxy Glass Sheet available, including 3240, G11, FR-4, G10 and so on.
Against the backdrop of global energy transition, new energy vehicles are reshaping the landscape of the traditional automotive industry at an unprecedented pace. As core components of new energy vehicles, batteries, traction motors and charging infrastructure have growing demand for insulating materials. As a critical type of insulating material, Insulation Sheet plays an irreplaceable role in the new energy vehicle sector.
Behind the reliable operation of electrical equipment, industrial machinery, renewable energy systems, and modern electronic devices lies a critical yet often overlooked component—insulation materials.
Mica Board is manufactured by bonding mica paper with organic silicone adhesive, followed by heating and hot pressing. It is a high-performance electrical insulation and thermal insulation material. The available colors are typically gold and white.
Mica Paper is widely recognized as a “core material” in high-temperature electrical insulation applications. With its outstanding thermal resistance, electrical insulation performance, and stable chemical properties, it plays a critical role in modern electrical, industrial, and high-tech engineering systems.
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