Double wall pipe providing intermediate chamber for lambda sensor support - is insulated to prevent loss of heat from exhaust gas of motor vehicle so that catalyser can be effective from cold start

摘要

The pipe (3) which is constructed with a double wall (10, 11) over at least part of its length has an inner (11) and outer (10) pipe section having an intervening airspace (15) which provides a thermal insulating layer. Both inner and outer (10) pipe sections are pierced (34) to receive a bush (16) which is welded in position to form a threaded (21) entry for a lambda-probe (not shown) as used for the determination of exhaust gas (5) composition. A sealing ring (not shown) ensures a gas-tight bush (16) and extends to the inner pipe to prevent the entry of gas into the airspace (15). USE/ADVANTAGE - Provides efficient thermal insulation wherein operating temp. for good catalytic action during processing of emissions is quickly reached. Enables wide choice of location for mounting probe.