Place of Origin: China (Mainland)                                          Brand Name: XINCHENG

Model Number: bakelite Tube for transformer( bkl)          Type: bakelite Tube for transformer( bkl tube )

Application: High Voltage                                                        Temperature grade: E class (120℃)

Material: phenolic resin and cable paper                             Use: Fit for insulating parts

Rated Voltage: 33KV                                                               Tensile Strength: ≥60Mpa

Water absorption: Wall thickness 3mm≤8%                     Thermostability(24h): 120℃

Flexural strength: ≥60.0Mpa                                            Keywords: phenolic laminated paper tube

Standard color: Natural color                                           Type: Insulation tube

Outer diameter: 10-1400 mm /customized                      Length: 1000mm /customized

Certification: ISO9001:2000 , CE/ROHS                         Services: OEM,ODM,CNC available

Standard: IEC61212-1:2006



Product Description

The phenolic aldehyde paper laminated tube is made up of rolling paper which is first soaked in phenolic resin, and then be heated, rolled and pressed, baked and solidified. It has very good dielectric property, and is applicable to be a part of insulating structure in electrical equipment.

High Density Insulation Material Bakelite Tubes phenolic laminate paper tube for electric equipment

phenolic paper laminate pipe has certain mechanical strength and electrical properties and is applicable to motors, electrical appliances and other electrical equipment. It can be used in transformer oil.


Phenolic paper laminated tube is made of insulating paper or insulating impregnated paper impregnated with phenolic resin, heated by rolling, baking and curing from the phenolic laminated paper tube.


This product has a high mechanical, heat and dielectric properties.


Suitable for electrical equipment for insulation structure parts, and can be used in humid environments and transformer oil.


It is suitable for mechanical & electrical applications, with good electrical properties in oil and under normal conditions;



Technical data:

Properties Unit Grade
Phenolic Paper Laminate Tube
Inside diameter(5-25mm) Inside diameter (>25mm)
Density g/cm3 ≥1.03 ≥1.20
Water absorption rate % Wall thickness 3mm   ≤8
Thermostability(24h) °C 120 120
Flexural strength MPa ≥50.0 ≥60.0
Compressive strength MPa ≥50.0 ≥60.0
Shear strength MPa
Dissipation factor 50Hz ≤0.03 ≤0.03
Dielectric strength perpendicular to laminations(withstand voltage) kV/mm Wall thickness 1.5-2.5mm ≥8.5 ≥8.5
(in 90±2°C/5min transformer oil) >2.5-3.5mm ≥8.0 ≥8.0
>3.5-4.5mm ≥7.0 ≥7.0
>4.5-6mm ≥6.5 ≥6.5
>6-9mm ≥6.0 ≥6.0
Dielectric breakdown parallel to laminations (in 90±2°C/5min transformer oil) kV 20 25
Surface withstand voltage (in case of humidity, under normal condition air withstand voltage 1 min) kV 12 12


Electrical winding paper immersed with phenolic resin and partially curing, then baking and finished by hot rolling. Heat resistance class is E class.

3520 has good mechanical and electrical property, can be used for motors and electrical equipment, also can be used for transformers.


Phenolic Paper Tube Technic data:

1 DENSITY g/cm3 ≥1.10 1.14  GB/T3172-1999
(120 degree ,/24 H )
No crack,
no muster
No crack,
no muster
(in oil 90°C ,five minutes)
8.0MV/m 8.0MV/m pass
5 DIELECTRIC LOSS FACTOR ≤3×10-2 2.1×10-2
Note: the sample is prepared by the client.
The following blanks



Packaging & Delivery

Outer packaging Details: pallets

Inner packaging Details

  1. Special packaging: Wrapped with packaging film and packed in carton.
    Class A: carton + wooden + iron packaging
    Class B: bubble bag + carton + plastic packaging
    Class C: bubble bag + carton + particles bag
    Class D: bubble bag + carton
    Normal packaging: carton
    3. Convenience packaging: PE bag, particles bag.
  2. Store it in dry and clean room at room temperature and keep it from moisture. The storage period is 12 months.

Delivery Detail:  Shipped in 20 days after payment



Our Services

We also CNC to your CAD drawing, cut to size customized, and sell full sheets in quantity. This epoxy glass fabric laminated sheets material is also available THINNER and THICKER. Please call our Sales Department for information.



1.What is the minimum ordering quantity ?

MOQ can be a small quantity even 10 kgs to meet various needing .

2.Do you have stocking for different thickness ?

Yes, We have 25 tons stock for common stock . Production time is very fast if one certain not in stock .

  1. Can we order mixed thickness for one order ?

Yes, We could match your ordering request even mixed different  thickness and colors .

4.Can you give me a discount price?

It is depending on the volume, the larger the volume is ,the more discount you can enjory.

  1. What are your design capabilities?

We have staff trained in AutoCAD and several design programs. We can work with many  different file formats, as well as develop designs based on sketches, drawings, blueprints and other formats.