New Products # 1995 Edinburgh
For reasons of environment and energy savings, the sales of High Efficiency Boilers have been stimulated in the last years. The low temperature flue gas emission which is characteristic for these boilers, leads to condensation of the flue gases in the chimney, attacking the masonry. The condensates contain aggressive components such as H2S04, HCI and HN03 with a pH value of 2-3. The use of traditional lining materials such as Stainless Steel, Aluminium or glass are either technically or economically unattractive. Furthermore, these materials, mainly camed out in a rigid form, do not permit easy installation in renovation projects. After evaluating a number of technopolymers, Polyvinylidene Fluoride (PVDF) has been chosen as a basis for the development of a complete lining system for chimneys. The system consists of flexible and rigid pipes and a wide range of fittings covering the needs for all installation situations. The design of the system has had to take account of working temperatures of up to 160°C and the said aggressive condensate. The flexible pipe has been developed especially for easy installation into chimneys. The special jointing system is capable of withstanding high axial forces at high temperatures and maintaining its tightness. Several years of experience have shown now that PVDF combined with good design criteria gives a much longer lifetime expectation than every other available material. Approvals have been obtained in several European countries.