Thinwall ™ Pre-Impregnated Phenolic Tubing

General Description

Thinwall ™ tubing is produced from a dielectric kraft paper that has been pre-impregnated with a special phenolic resin and cured to the Class B stage. After forming, tubes are baked to complete the resin cure. In this process, the phenolic and the special adhesive coalesce to form a complete homogenous product. (For round phenolic resin impregnated tubing, see "Resinite").

Material Properties* :
Dielectric strength- VPM min:  165
AlEE Temperature Class - °C:  90(0) to 105(A)
Specific Gravity: .85
* Based on 10 mil sheet, as provided by mill before forming.
Patent No 3,314,133.


Additional Information

Advantages: This patented tubing was developed to provide many of the desired properties of round Resinite phenolic impregnated tubing in both square and rectangular shapes. It has excellent mechanical strength as well as good electrical properties. Strength for strength, Thinwall™ can provide a much thinner wall than kraft, and will hold its shape better than kraft; particularly under humid conditions. The extra strength and thinner walls allow a wire saving up to 10%. It is excellent for fabrication purposes. It is available as a 100% phenolic material or can be combined with dielectric kraft for special properties and lower cost.

Minimum Wall Thickness:.010" (Combination Construction) 
.015" (P-100 Construction)

Suggested Uses: Coil forms, collars, spacers, terminal rings and tubes, motor-switch hardware, high strength, corrosion resistant tubing for mechanical applications, fuse parts, shafts.


Thinwall ™ - Kraft Construction
P-100: 100% phenolic impregnated material in square or rectangular forms. No kraft is used. Strength is maximum and is approx. 40% stronger than kraft. P-100 offers minimum cutting burrs. For relatively large coils where rigidity is required. Pieces may break off in lead picking if care is not exercised.
P-60: 60% phenolic - 40% kraft buried. Offers minimum cutting burrs. Tubing made with this construction is approx. 30% stronger than kraft. With the addition of the buried kraft, it will not shatter. Best general purpose "Thinwall" tubing.
PL-60: 60% phenolic lined - 40% kraft overwrap. Same strength as P-60. Phenolic lining aids in insertion and laminations. Kraft overwrap provides easier lead picking.
PO-60: 60% phenolic on outside - 40% kraft lining. Choice of PO-60 or PL-60 depends on whether minimum cutting burrs are required on outside or inside of tube wall.
PB-60: 60% phenolic buried within 40% kraft. Kraft acts like a protective covering. This construction has some cutting burrs but less than kraft alone.
P-30: 30% phenolic - 70% kraft buried. Lowest cost construction that still retains increased strength over kraft alone. Approx. 20% stronger that kraft. Helps prevent twisting. Still provides minimum burrs with phenolic on outside.
PL-30: 30% phenolic lined - 70% kraft overwrap. Same strength as P-30. Phenolic lining aids in insertion of laminations.
PO-30: 30% phenolic on outside - 70% kraft lining. Choice of PO-30 or PL-30 depends on whether minimum cutting burrs are required on outside or inside or tube wall.
PB-30: 30% phenolic buried within 70% kraft. Basically, a kraft tube but with higher strength and less tendency to twist.


Additional Tubing Resources (PDF Downloads)