Insulators
Composite insulators with HTV silicone housings on brittle-fracture-resistant ECR glass-fiber cores: 3FL long-rods for suspension and tension on overhead lines (SML 70–630 kN, up to 800 kV), hollow-core housings for apparatus, and station posts.
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Most-documented entries in this area — full specifications, downloads and orderable designations.
3FT Composite post insulator 3FT
SCL 18 – 150 kNm (3FT2 – 3FT7) · Unit length 0.5 – 5.5 m, stackable · AC & DC, systems up to 800 kV Datasheet · Dimensions ↓
3FL8 Composite long-rod insulator 3FL8
Um 72.5–800 kV (3FL family) · SML 70–630 kN (3FL family; per-type by order code) · Creepage factor 2.8 / 3.5 / 4.5 (three shed profiles) Datasheet · Dimensions ↓
3FL2 Composite long-rod insulator 3FL2, ≤ 70 kN
SML up to 70 kN · Um 12 – 72.5 kV · Creepage class > 31 mm/kV Datasheet · Dimensions ↓
3FL4 Composite long-rod insulator 3FL4, SML 120 kN, 72.5 – 550 kV, HTV silicone on ECR FRP rod, suspension & tension
SML 120 kN · 72.5 – 550 kV · HTV silicone Datasheet · Dimensions ↓How to choose an insulator
Mechanical class first — the specified mechanical load (SML) of the string sets the 3FL size — then system voltage and pollution class set housing length and creepage. Silicone's hydrophobicity transfer keeps pollution performance high in coastal and industrial environments.
- Overhead-line suspension/tension → 3FL2–3FL8 by SML class
- Apparatus housings (arresters, bushings, instrument transformers) → 3FH hollow-core
- Substation busbar support → 3FT station posts
Official brochures — current online editions
Mirrored from the published marketing literature on siemens-energy.com; source links included.
Technical documentation
13 documents available across this area — datasheets, catalogs and drawings.
Flyer 3FL long rod insulators — Composite technology up to 800 kV Flyer 3FL long rod insulators — Composite technology up to 800 kV (Siemens Energy, 2021) Product guide Power Engineering Guide Ed. 7.1 — Ch. 4 Products and Devices, §4.10 Silicone Long Rod Insulators (3FL2 technical data, p. 251) Brochure Portfolio of surge arresters & composite insulators (3FL and 3FS/3FT family overview)Own or operate this equipment?
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