Fibreglass tubes made of fibre glass based on epoxide resin or silicone resin or quartz glass for production of impeder casings for high-frequency welding of steel tubes.
The correct choice of impeder casing’s material for producing steel tubes by high-frequency welding is of primary importance because it is no sense to use high-quality energy saving ferrite cores without their reliable protection providing. Thanks to it more than 20-year long operation experience, USM Company succeeded in developing and making advanced and reliable materials for using as protective casing of impeders.
Advantages of using USM made fibreglass tubes are high mechanical strength, capability of long-term operation at high temperatures, ideally flat surface preventing a sticking to it any drops of melted metal.
Characteristics of FibreGlass Material
| Type | WT912 | WT2000 | BK |
| Maximum working temperature | 180 °С | 220 °С | 280-300 °С |
In most cases main material used for production of impeder casings is Fibreglass WT912 (green line) based on epoxide resin. For higher temperatures it is possible to use following materials:
BK (Quartz Glass Casing) based on quartz glass. After 1000 hours of operation at a temperature of 280-300 °C this material does not deteriorate its parameters.
MICA (Silicon Resin Casing). This material is characterized by increased maximum working temperature (450-500 °C) and has a small thickness of walls – as little as 2-3 mm.
Standard Sizes and Thickness of Tubes for Impeder casings
| Inner Diameter, mm | Tube Thickness, mm | ||||||||
| 4…6 | 0.5 | 0.75 | 1 | 1.5 | 2 | 2.5 | 3 | ||
| 6…10 | 0.5 | 0.75 | 1 | 1.5 | 2 | 2.5 | 3 | ||
| 10.5…15 | 0.5 | 0.75 | 1 | 1.5 | 2 | 2.5 | 3 | ||
| 15.5…20 | 0.5 | 0.75 | 1 | 1.5 | 2 | 2.5 | 3 | 3.25 | 3.50 |
| 20.5…25 | 0.5 | 0.75 | 1 | 1.25 | 1.5 | 2 | 2.5 | 3 | |
| 25.5…30 | 1 | 1.5 | 2 | 2.5 | 3 | ||||
| 30.5…35 | 1 | 1.5 | 2 | 2.5 | 3 | ||||
| 35.5…40 | 1 | 1.5 | 2 | 2.5 | 3 | ||||
| 40.5…45 | 1 | 1.5 | 2 | 2.5 | 3 | ||||
| 45.5…49 | 1 | 1.5 | 1.75 | 2 | 2.5 | 3 | |||
| 50…55 | 1.5 | 2 | 2.5 | 3 | 4 | ||||
| 56…60 | 1.5 | 2 | 2.5 | 3 | |||||
| 61…65 | 1.5 | 2 | 2.5 | 3 | |||||
| 66…70 | 1.5 | 2 | 2.5 | 3 | |||||
| 71…75 | 1.5 | 2 | 2.5 | 3 | |||||
| 76…80 | 1.5 | 2 | 2.5 | 3 | |||||
| 81…85 | 1.5 | 2 | 2.5 | 3 | 4 | ||||
| 86…90 | 1.5 | 2 | 2.5 | 3 | |||||
| 91…95 | 1.5 | 2 | 2.5 | 3 | |||||
| 96…100 | 1.5 | 2 | 2.5 | 3 | |||||
Casing tubes with other dimensions are issued on additional order. An order, issue of rectangular-shaped and square-shaped products is also possible.
To make an assembly impeder, tubes may be equipped with blind plugs (Celeron Bars), which are supported at USM warehouse with diameters from 5 to 90 mm.
