DHD Design Features
Furnace
A major advantage of the horizontal configuration of the DHD series is its superior thermal uniformity. A horizontal furnace is not subject to convection parallel with the specimen, and can be made a lot more symmetrical than a vertical one. For long specimens, a horizontal system is a must to ensure reasonable thermal uniformity. The DHD-1000 features an air-cooled shell around a water cooled Ni-Cr wound muffle flange to support testing temperatures from ambient to 1000°C. The plate specimen furnace of the DHD-300 is designed to test polymers and other low thermally conductive materials over the range -150 to 300°C by lacing the flat specimen in direct contact with the heating/cooling surface to minimize thermal lag during controlled-rate heating/cooling. Any two furnaces can be configured on a single platform. Additional furnaces can be easily exchanged by the user.
Specimen Holder
The dual DHD-1000 specimen holders and pushrods are constructed from selected grade fused-quartz with matched construction. Featuring an integral specimen cradle, they are designed for easy removal and exchange. The DHD may be operated either as a two-specimen absolute or a conventional differential dilatometer for the highest sensitivity for very small expansion on low-CTE materials.
Technical Specification