What is Liquid Paper®?

From a chemical point of view, NOMEX insulation paper is an aromatic polyamide, collectively referred to as aromatic polyamide. The molecular structure of the material is particularly stable, which is why the properties of NOMEX paper are produced. NOMEX insulation paper is made of polymers of two forms of aramid. The fine fibrous binder particleschromatographic fibersare cut directly from the polymer under high shear. These particles are mixed with a certain length of short fibers cut from the filaments. Where electrical insulation is required, NOMEX® Aramid products are usually found. It has a unique and appropriate performance balance and has been widely used for many years in transformers, motors, generators and other electrical equipment to improve the reliability of electrical insulation.

NOMEX insulation paper

discuss

From a chemical point of view, NOMEX insulation paper is an aromatic polyamide, collectively referred to as aromatic polyamide. The molecular structure of the material is particularly stable, which is why the properties of NOMEX paper are produced. NOMEX insulation paper is made of polymers of two forms of aramid. The fine fibrous binder particleschromatographic fibersare cut directly from the polymer under high shear. These particles are mixed with a certain length of short fibers cut from the filaments. Where electrical insulation is required, NOMEX® Aramid products are usually found. It has a unique and appropriate performance balance and has been widely used for many years in transformers, motors, generators and other electrical equipment to improve the reliability of electrical insulation.

Chinese name

NOMEX insulation paper

English name

NOMEX insulation paper

From a chemical point of view, NOMEX insulation paper is an aromatic polyamide, collectively referred to as aromatic polyamide. The molecular structure of the material is particularly stable, which is why the properties of NOMEX paper are produced. NOMEX insulation paper is made of polymers of two forms of aramid. The fine fibrous binder particleschromatographic fibersare cut directly from the polymer under high shear. These particles are mixed with a certain length of short fibers cut from the filaments.

The two components of short fiber and chromatography fiber are mixed in a water-based slurry, and then made into a continuous sheet structure by a special paper machine. The density of the paper that has just come out of the machine is low and it has only moderate mechanical and electrical properties.

Densification and internal bonding are then achieved by high-temperature calendering. The NOMEX insulating paper produced in this way has high mechanical strength, flexibility and good electrical properties, and can maintain its characteristics at higher temperatures.

Where electrical insulation is required, NOMEX® Aramid products are usually found. It has a unique and appropriate performance balance and has been widely used for many years in transformers, motors, generators and other electrical equipment to improve the reliability of electrical insulation.

NOMEX® material series is available in various models to suit different application requirements

Nomex Eight Features:

Inherent dielectric strength

The calendered NOMEX® products can withstand short-term voltage field strength of 18 ~ 40KV / mm, and do not need further treatment with varnish and resin. Because NOMEX® products have low dielectric constant, the Electric field distribution is more uniform;

Mechanical toughness

The calendered NOMEX® products have very high strength and good elasticity, tear resistance and abrasion resistance, while thinner products have flexibility;

3. Thermal stability

NOMEX® products are approved by UL material temperature class 220 ° C, which means that they can maintain effective performance for more than 10 years even if they are continuously placed at 220 ° C;

4. Chemical compatibility

NOMEX® is largely unaffected by most solvents and is very resistant to acid and alkali corrosion. It is easily compatible with all varnishes, adhesives, transformer fluids, lubricants, and coolants. In addition, NOMEX® is not damaged by insects, fungi and molds;

5. Low temperature performance

At the boiling point of nitrogen (77K), the tensile strength of Nomex® T410 insulating paper and Nomex® 993 and 994 laminates exceeds the strength value at room temperature;

6. Not sensitive to moisture

When NOMEX® products are 95% wet, their dielectric strength is 90% in a completely dry state, and at the same time, many mechanical properties have actually improved;

7. Radiation resistance

Even if the intensity of ionizing radiation reaches 800 Mrad (8 Mgray), NOMEX® products are basically unaffected, and they retain their mechanical and electrical properties after 8 doses of this radiation;

8. Non-toxic / flammable

NOMEX® products do not have any known toxic effects on humans or animals. Nomex® products do not melt in the air and do not support combustion. And their oxygen limit index (LOI) is greater than 20.8 at 220 ° C (normally empty combustion threshold Value), so it will not burn. NOMEX® products meet the flame resistance requirements of UL94V-0;

NOMEX® insulation paper

T410

It is a calendered insulating paper with high inherent dielectric strength, mechanical toughness, flexibility and resilience. Nomex T410 has excellent flame retardant properties.

Scope of application: T410 can be widely used in most electrical equipment. It has 12 thicknesses (0.05-0.76) (2-30mil) and is used for almost all known electrical tablets.

T411

Without calendering, it is the predecessor of NOMEX® T410 paper. Its thickness is 0.13 ~ 0.58mm, specific gravity is 0.3, and its electrical and mechanical properties are relatively low. This product is mostly used for motor phase insulation and transformer coil insulation. Here, the thickness and adaptability of the product are relatively high. T411 is also easier to penetrate and saturate.

T418 / T419

Add 50% mica in the paper making process, and its thickness is 0.08 ~ 0.36mm. It has stronger insulation voltage resistance and corona resistance. It can be used for insulation of motor wires and coils, transformer grounding and interlayer insulation.

T418 is a calendered product with high inherent dielectric strength. T419 is uncalendered and has a thickness of 0.18 and 0.33mm. It is used in applications with high requirements on adaptability and saturation.

N196

Its characteristic is that the surface has many thin tubes, which can quickly penetrate the resin and varnish. The product has a specific gravity of 0.7 and good mechanical properties. It is mostly used in places with high requirements for impregnability.

NOMEX® laminate

Unlike Nomex® insulation paper, it has a high thickness and rigidity, which can be used as the oil channel and enclosure of oil-immersed dry-type transformers, as well as the insulation of motor ends.

993

It is a low-medium density laminate with a thickness of 1.0 ~ 4.5mm. The material itself is rigid and flexible, and has good saturation and electrical properties.

994

It is a compact modification of Nomex® 993 laminated leather, with a thickness of 1.0 ~ 9.6mm and a specific gravity of 1.

When manufacturing traction transformers, the following measures need to be taken after using NOMEX insulation paper .

(1) Strengthen the calculation of the temperature rise of the transformer winding and strictly control the temperature rise of the winding.

(2) Use simulation calculation software to simulate the internal temperature of the transformer to provide a basis for determining the boundary between the two materials of NOMEX insulation paper and ordinary insulation paper. Based on the characteristics of the transformer oil itself, reasonably determine the use limit of the two materials. Avoid the danger of oil and ordinary insulation paper cracking, insulation electrical breakdown or thermal breakdown.

(3) Increase and improve the oil circuit in the coil to reduce the temperature rise of the transformer oil and avoid oil cracking.

(4) Improve the external cooling system, increase the cooling capacity of the transformer, and reduce the temperature rise during normal load of the transformer.

(5) Improve the support of the inner coil on the circumference, so that the transformer can withstand the mechanical pressure caused by high overload and short circuit.

According to the traction load of electrified railways, new insulation materials are used in the manufacture of traction transformers. Nomex insulation paper replaces ordinary insulation paper, which improves the overload capacity of the transformer, reduces the installation capacity of the traction transformer, and reduces the cost of basic capacity, thereby reducing electrification Railway operating costs have good application prospects.