MARINE ENGINES.
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between the flanges, having a spindle forged on, and passingthrough the cap; they have a screw cut on the end with nut andlock nut fitted, by which means the brasses can be tightened up oradjusted at any time. In other arrangements a single wedge pieceis introduced, having one central spindle fitted with two nuts fortightening up against the cap. Some makers introduce the brassesin four parts, one at each side and one at the top and bottom; bythis means they can be adjusted vertically and longitudinally.
The condenser .—We now come to consider the arrangements foreffecting the condensation of the steam with ordinary injectioncondensers. All condensing vessels should be constructed as simplyas possible; and the arrangement of the water pipes leading intoand from them, as well as valve seats, discharge chambers or hot
wells, and all their vari-ous fittings, requirescareful consideration.Where large flat sur-faces are required, theyshould bewell strength-ened with ribbed barsin the casting; somemakers use wrought-iron stays, which tendgreatly to strengthenthe condensing vesselagainst collapsing. The other parts of the general casting must bewell bound with the various divisions required for the air pump andvalve fittings. The capacity of the condenser is greatly afifectedby the size of the exhaust pipe from the cylinder; this pipe shouldhave a large area, so as to freely pass the steam to that part of thecondenser where the water from the sea is showered in; thus thelarge pipe receives the steam, which is at once Condensed, and thecapacity of the condensing vessel need not be so large as when theexhaust steam finds its way into a condenser placed alongside ofa cylinder having no pipe connection.
The exhaust pipe should be fitted with an expansion joint, whichis generally placed on the condenser casting, the end of the pipepassing through a loose hoop placed at the bottom of the stuffingbox; by this means the pipe can be angled into its place withoutdisturbing the cylinder or condenser. The loose hoop and gland