Bimetal Connecting Tube (Oil-Sealed) — GTL Series
GTL bimetal connecting tube for inline splicing from aluminium cable to copper cable/bus.
Friction-welded Cu–Al body with oil seal design for stable, low-resistance joints.
Straight through-type sleeve; sizes 16–500 with full D / d / D1 / D2 / L2 / L1 / L matrix.
Ideal for transformers, switchgear, feeders, and outdoor distribution.
Overview — GTL Bimetal Connecting Tube (Oil-Sealed)
The GTL Series is a bimetal (Cu–Al) connecting tube used for inline splicing where
aluminium conductors must transition to copper conductors or copper busbars. A friction-welded copper section and
aluminium section provide excellent conductivity and mechanical strength, while the oil-seal structure
improves corrosion resistance and long-term stability in demanding environments.
Type: Through-type bimetal connecting tube (GTL, oil-sealed) |
Materials: Copper (T2) + Aluminium (L3), friction-welded |
Use: Cu–Al transition splice for round/sector cables |
Dimensions: D, d, D1, D2, L2, L1, L (see table)
Technical Data — Dimensions (mm)
| Type | D | d | D1 | D2 | L2 | L1 | L |
|---|---|---|---|---|---|---|---|
| GTL-16 | 9 | 6.8 | 10 | 6.8 | 26 | 40 | 66 |
| GTL-25 | 10 | 6.8 | 11 | 7.8 | 26 | 41 | 67 |
| GTL-35 | 11 | 6.8 | 13 | 8.5 | 32 | 43 | 75 |
| GTL-50 | 12 | 8.5 | 15 | 9.8 | 32 | 51 | 83 |
| GTL-70 | 14 | 9.5 | 17 | 11.5 | 38 | 55 | 93 |
| GTL-95 | 16 | 10.5 | 20 | 13.8 | 40.5 | 58 | 98 |
| GTL-120 | 19 | 13.5 | 15.5 | 43 | 64 | 107 | — |
| GTL-150 | 21 | 16 | 27 | 16.8 | 48 | 66 | 114 |
| GTL-185 | 23 | 18 | 27 | 18.8 | 48 | 72 | 120 |
| GTL-240 | 25 | 21 | 30 | 21 | 53 | 72 | 125 |
| GTL-300 | 28 | 24 | 33 | 23 | 57 | 78 | 135 |
| GTL-400 | 30 | 26 | 32 | 27 | 59 | 81 | 140 |
| GTL-500 | 34 | 29 | 34 | 27 | 63 | 87 | 150 |
Installation Notes
- Use as a Cu–Al transition splice; match each side to the respective conductor metal.
- Clean strands; for aluminium, apply oxide-inhibiting compound before insertion.
- Crimp progressively along the tube using the specified dies to reach rated pull-out strength.
- Seal ends (heat-shrink or sealing compound) to maintain the oil-seal and environmental protection.
