HC Deb 30 May 1892 vol 5 cc201-2
MR. GOURLEY (Sunderland)

I beg to ask the First Lord of the Admiralty if it is correct that it has been found necessary, in order to prevent leakage, to fit ferrules to some of the tubes of the "Royal Sovereign"; if so, is it in consequence of the boilers being of a similar type to those of the "Thunderer"; and whether he anticipates that the ferrules proposed to be used in the tubes of the "Thunderer," "Vulcan," and other vessels will prevent the unequal distribution of heat consequent upon the boilers being constructed with single combustion chambers?

*LORD GEORGE HAMILTON

The ferrules in question will improve the working efficiency of any type of boiler to which they can be fitted; and in order to test this in extended practice, the "Royal Sovereign," which is about to proceed on service in the Channel, has, with other vessels, been selected for a trial of the ferrules. Her boilers are not of the same type as those of the "Thunderer." Those ferrules do not prevent the unequal distribution of heat, but they tend to counteract in the weakest part of the boiler the injurious effect of the contraction and expansion of the tube plate and tubes consequent upon variations in the heat of the combustion chamber.