FRP Dogbone

Our frp dogbone is made of fiberglass reinforced plastic. The cross-section shape looks like a dog bone. It also looks like the letter "I". That is why the English name is dogbone. The Chinese name is I-shaped support strip. Where is the frp dogbone used? When winding transformer coils, you need to create an oil duct between the coils. Transformer oil flows through the duct. The oil provides cooling and insulation. The frp dogbone is placed between the coils. It holds them apart. It creates a gap for the oil to flow. Why is the shape an "I"? The I-shape has two wide edges. One edge touches the upper coil layer. The other edge touches the lower coil layer. The middle is narrow. Oil can flow through the hollow space on the sides. This gives good cooling. A solid square bar would block the oil flow.

A large power transformer company came to us. They used to use wooden spacers. Wood absorbs moisture. Over time, it deforms. Also, wood is not flame retardant. We recommended our frp dogbone. It does not absorb moisture. It does not deform. It is flame retardant at V0 level. They tested it and switched to our product completely. Now they buy 100,000 meters of our frp dogbone every year. The performance data is as follows. Bending strength is 200 MPa. Compression strength is 150 MPa. Temperature class is F (155°C). Flame retardancy meets UL94 V0. Breakdown voltage is 10 kV. Water absorption is less than 0.2%. We can make heights from 3 mm to 20 mm. Widths from 5 mm to 15 mm. Lengths from 500 mm to 2000 mm. The dimensional tolerance is ±0.1 mm. We use special molds. The pultrusion process gives stable dimensions.