Section 45.—JETS, NOZZLES, AND INJECTORS.
[794]. Straight jet, for long distances.
[795]. Short jet.
[796]. Rose jet, for spreading.
[797]. Fan jet, or spreader.
[798]. Blast tuyere.
[799]. Smith’s tuyere and water bosh.
[800]. Jet aspirator, for inducing a mixed current of air and water or steam.
[801]. Steam jet pump; the steam enters by the central jet and causes a vacuum, into which the water rises by the branch pipe.
[802]. Insufflator for steam and air blast; used also as a petroleum injector, &c.
[803] & [805]. Spray jets; the liquid rises by gravity at the small vertical nozzles, and is driven in a spray or mist by a cross blast of air from the horizontal jets.
[804]. Injector. The varieties of this contrivance are too numerous to specify. See Graham’s, Gifford’s, Hall’s, Hancock’s, and others in common use.
[806]. Plain or spreading jet. The eight vanes can be pushed into the jet of water to cut it up by moving the sliding ring.
[807]. Ventilating jet or aspirator, with several lateral openings for inducing a current.
Jet condensers. See [Section 25].
Section 46.—JOURNALS, BEARINGS, PIVOTS, &c.
See also [Section 70].
[808]. Plain or solid pedestal.
[809]. Half bearing, sometimes used without a cotter.
[810]. Half bushed bearing, having a half brass on the lower side only.
[811]. Chambered long bearing.
[812]. The ordinary double brassed pedestal or plummer block; sometimes made with the cap and joint of brasses at an angle of 45° when the shaft is subject to horizontal thrust. Numerous modifications of this bearing exist.
[813]. Slot bearing for rising and falling spindle.
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[814] & [815]. End thrust bearings.
[816]. Sliding bearing, with vertical or horizontal traverse.
[817]. Double V bearing to accommodate different sizes of shafts.
[818]. Vertical shaft footstep.
[819]. Vertical pivot.
[820]. Horizontal pivot and set screw; the screw should have a lock nut to prevent it being worked back by the motion of the spindle.
[821]. Conical neck, usually with steel bush.
[822]. Spherical footstep, to allow the shaft to sway out of the perpendicular.
[823]. Horizontal bearing, allowing the shaft to run out of line.
[824]. Balanced bearing, to bear the weight of a light shaft, and placed between the fixed bearings.
[825]. Self-adjusting bearing for line shafts, with ball and socket movement.
[826]. Ball and socket bearing for vertical spindle, allowing considerable variation from a right line.
[827]. Horizontal thrust bearing, with multiple flanges and double brasses, each capable of separate adjustment; used for screw shafts in steam-ships.
[828]. A form of pedestal, with the cap provided with end joggles to prevent looseness.
[829]. Trunnion bearing, for oscillating cylinders, &c. The steam is conveyed through the bearing, which has a stuffing box and gland to prevent leakage.
[830] & [832]. Swinging support for a shaft, having a sliding bevil gear or other motion upon it which has to pass the swinging support; used for lathe sliding gear, overhead travellers, &c.
[831]. Ball and socket centre for car bogies, &c.
[833]. Pedestal with side adjustment for the brasses by taper keys and screw adjustments.
Bearings running under water are generally lined with strips of lignum vitæ and require no lubricant.
So-called self-lubricator bearings are in use, lined with strips of patent composition metal.
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[834]. Centre bearing, with annular grip, for a heavy centre piece or car bogie.
[835]. Centre bearing, with allowance for some amount of oscillation.
Coupled bearings. [No. 671].