Dry-type transformer winding
A shaped insulating support or winding interface where the contact faces, section and continuous length must fit the coil assembly.
F1-FORM· Custom pultruded profile
Fiberglass dog bone profiles for electrical equipment
A drawing-led pultruded GFRP shape for transformer winding and insulating support assemblies. Match the dog bone section, material grade and qualification plan to your equipment before production.
FIG. 1 Dog bone cross-section conceptSchematic · not to scale
A shaped support designed around the equipment
Continuous glass reinforcement and a cured polymer matrix form a consistent pultruded length. The widened ends provide defined contact regions while the narrower waist creates clearance for the surrounding assembly. Actual geometry is established by the equipment drawing.
The supplier reference page identifies transformer core winding, dry-type transformers, reactors and other high-voltage equipment as typical uses. Its published figures and certification claims describe that supplier's offering; this page does not present them as verified F1 product data.
Where a dog bone section may fit
These are design contexts from the supplier reference, not automatic approvals for an F1 grade or an installed high-voltage assembly.
Reactors and power equipment
A nonmetallic spacer or support profile used around coils and other components, subject to the equipment maker's electrical and mechanical design.
High-voltage assemblies
A custom insulating section for capacitors, disconnectors or power modules when creepage, clearance, finish and attachment details have been reviewed.
Define the profile before asking for a price
The section, process and test scope should be fixed together. A supplier's generic property table cannot replace the data for a selected production grade.
| Specification field | What to send | Review before release |
|---|---|---|
| Cross-section | End widths and radii, waist width, overall height, bearing faces and tolerances | Approve a dimensioned drawing or physical sample before tooling release |
| Length and processing | Cut length, end finish, holes, slots or other machining and their tolerances | Check exposed fibers and edge finish after secondary operations |
| Material system | Glass reinforcement, resin, color, surface finish and operating environment | Select a production grade for the required thermal and environmental duty |
| Electrical duty | System voltage, insulation arrangement, creepage and clearance, test method | Qualify the finished profile and assembled equipment for the actual duty |
| Mechanical duty | Support loads, restraint method, winding pressure, vibration and temperature | Review the load path and request grade-specific test evidence |
Qualify the grade and finished assembly
Ask for the test method, specimen orientation, test conditions and report scope behind any quoted tensile, flexural, dielectric, moisture or temperature value. Check that the report applies to the proposed resin, reinforcement and section.
For electrical service, define the equipment-level voltage, creepage, clearance, partial discharge and thermal acceptance criteria. The equipment manufacturer remains responsible for validating the final design and installed assembly.
A practical approval sequence
- 1. Approve the dimensioned section and machining drawing.
- 2. Review the proposed grade and test plan against equipment requirements.
- 3. Check production samples in the intended assembly.
- 4. Release production only against agreed acceptance criteria.
Fiberglass dog bone questions
What is a fiberglass dog bone profile?
It is a pultruded glass-fiber reinforced polymer section with wider ends and a narrower middle. In electrical equipment, the shaped section can serve as an insulating support or winding interface. It is not a standardized test specimen or a universal replacement for an approved insulator.
Are standard dog bone sizes available?
The supplier reference shows example dimensions, but those are not an F1 stock list. Send a drawing or sample so we can check die availability, geometry, tolerances and production quantity before quoting.
Can you guarantee a voltage or temperature rating?
A rating depends on the selected material grade, section, surface, test method and final assembly. State the equipment standard and acceptance criteria in the RFQ; grade-specific reports and samples must be reviewed before a rating is used in design.
Can the profile be drilled or cut?
Cut lengths and secondary machining can be reviewed with the drawing. Holes, slots and exposed cut ends may change mechanical and electrical behavior, so their location, finish and inspection requirements belong in the approved specification.
Send the drawing and equipment duty
Start with the information you have. We can identify any missing dimensions or qualification inputs during review.
Attach the cross-section drawing and describe where the profile sits in the electrical assembly. We reply within one business day; a formal quotation follows once the specification and delivery are reviewed.
- Drawing
- Dimensioned cross-section, tolerances, cut length and any machining.
- Electrical duty
- Equipment type, voltage, insulation arrangement and required test methods.
- Service conditions
- Temperature, humidity, chemicals, vibration and expected support loads.
- Supply plan
- Sample quantity, production volume, packing, destination and target date.