LE Phenolic Tube — IDs, ODs, Wall Thicknesses & Lengths
LE phenolic tube is hollow cylindrical stock produced from NEMA Grade LE linen phenolic laminate — fine-weave cotton (linen) fabric saturated with phenolic resin and formed into tube by winding or compression molding. Ready Plastics stocks LE phenolic tube as insulating sleeve, conduit liner, and coil bobbin stock where the fine linen weave delivers a smoother interior bore and superior dielectric performance compared to canvas-grade tube. NEMA LI-1 governs Grade LE.
At a glance:
- OD range: approximately 0.375" to 6.0"
- Wall thickness: standard walls from 0.062" to 0.500"+
- Standard length: 48" (4 ft) per piece; cut-to-length available
- Tolerances: OD ±0.010", ID ±0.015" typical
- Material: NEMA Grade LE — fine-weave cotton-fabric phenolic laminate (NEMA LI-1)
- Production method: Wound or compression-molded thermoset
- Color: Natural tan
Standard Tube Size Table
LE phenolic tube is stocked in representative sizes:
| OD | Wall Thickness | ID (approx.) | Standard Length |
|---|---|---|---|
| 0.500" | 0.062" | 0.376" | 48" |
| 0.750" | 0.093" | 0.564" | 48" |
| 1.000" | 0.125" | 0.750" | 48" |
| 1.250" | 0.125" | 1.000" | 48" |
| 1.500" | 0.187" | 1.126" | 48" |
| 2.000" | 0.250" | 1.500" | 48" |
| 3.000" | 0.375" | 2.250" | 48" |
| 4.000" | 0.500" | 3.000" | 48" |
Non-standard OD/wall combinations available on request. Minimum order is one piece cut-to-length.
Mechanical & Electrical Properties
LE phenolic tube properties are based on the NEMA Grade LE laminate per NEMA LI-1:
| Property | Value |
|---|---|
| Tensile strength | 36,000 psi (245 MPa) |
| Flexural strength (LW, 0.125") | 18,000 psi (120 MPa) |
| Compressive strength | 13,000 psi (89 MPa) |
| Shear strength | 13,500 psi (93 MPa) |
| Bond strength | 1,900 psi (13 MPa) |
| M-scale hardness | 100 |
| Specific gravity | 1.34 |
| Water absorption (24 hr) | 1.8% |
| Flammability | UL 94HB |
| Max. operating temperature | 255 °F (125 °C) |
Lower water absorption (1.8%) means LE tube maintains stable bore dimensions and dielectric properties in humid operating environments better than CE tube.
Typical Applications
- High-dielectric insulating sleeves — LE phenolic tube provides conductor pass-through insulation in medium-voltage switchgear with a smoother bore than canvas grades
- Coil bobbins and winding forms — Fine linen weave produces consistent OD geometry for precision wire coil winding in transformers and chokes
- Precision conduit liners — Electrical conduit fittings and panel knock-outs accept LE tube liners for conductor-to-enclosure isolation
- Bushing cores — Pre-turned LE tube sections form the insulating core of custom compression bushings for motor terminal connections
- Spacer columns — Hollow LE tube cut to exact stack lengths maintains conductor and component spacing in relay and switchgear assemblies
- Bearing sleeves for electrical drives — Insulating bearing sleeve isolates motor shaft from frame ground in variable-frequency drive applications
Machining LE Phenolic Tube
LE phenolic tube turns cleanly on a lathe for OD facing, boring, and grooving using sharp carbide tooling. The fine linen weave tolerates tighter chip loads than canvas grades without surface delamination — useful when holding close diameter tolerances on thin-wall sections. Support thin-wall tube with a mandrel or internal plug before heavy OD cuts. Cross-drilling for radial holes is practical with carbide drills at low feed rate and a backing block at exit. Phenolic dust is abrasive — use dust extraction and appropriate respiratory protection.
Related
- LE Phenolic Grade Line Card
- LE Phenolic Rod — solid round stock for precision turned electrical insulators
- LE Phenolic Sheet — flat plate for terminal boards and switchgear insulating panels
- CE Phenolic Tube — coarse canvas grade for general-purpose insulating sleeve applications