A Textbook on Steam Engineering ...International Textbook Company, 1902 |
Συχνά εμφανιζόμενοι όροι και φράσεις
air chamber air cock amount armature arrangement attached binding post boiler bottom brake button cable car safeties circuit clip closed coil condensation connected counterweight crank crosshead cubic feet cylinder dashpot delivery pipe delivery valves diameter direct-acting pump discharge pipe door double-acting drain drum duplex dynamic brake electric elevators exhaust feet per minute floor flow gate valve gear heating surface horizontal horsepower hydraulic elevator lever lift limit stop live steam low-pressure machine magnet main valve motion motor moved operating device Otis Elevator Company packing passes pilot valve piston rod placed plunger port position pressure prevent radiator resistance reversing rheostat riser screw shaft shipper rope shipper sheave shown in Fig slide solenoid spur-geared square feet square inch starting stroke stuffingbox suction pipe suction valve supply pipe switch tank tion tube vacuum vertical water end water hammer weight
Δημοφιλή αποσπάσματα
Σελίδα 21 - ... cylinder and calculating the horsepower of the engine on the assumption that all the work is done in the low-pressure cylinder. To do this, the mean effective pressures of the two cylinders are found from indicator diagrams; the mean effective pressure of the high-pressure cylinder is then divided by the ratio of the volume of the low-pressure cylinder to that of the high-pressure cylinder, and the quotient is added to the mean effective pressure of the low-pressure cylinder.
Σελίδα 26 - Regulator. — Fig. 20 shows a regulating device much used in elevator work. Referring to the illustration, the operation is as follows: Steam from the boiler enters the regulator at the point marked "inlet" and passes through into the pump, which continues in motion until the required water pressure is obtained in the system, which acts through a ^-inch pipe connected at a and upon the diaphragm D. This diaphragm is raised by the excess water pressure and carries with it the weighted lever...
Σελίδα 4 - Multiply the square of the diameter of the pipe in inches by . 7854 ; then multiply the result by 100 ; the result is the total amount of heating surface in square feet which the pipe will supply. EXAMPLE.— What amount of direct heating surface may be supplied by a steam pipe 7 inches in diameter ? SOLUTION.— 7
Σελίδα 8 - ... in turn gives steam to the steam piston P and operates the pump. The main valve v is a plain slide valve of the B form working on a flat seat. The chest piston has a rod R to which is clamped an arm S, the latter being connected to the rocker bar T by a link /. The main piston rod carries an arm O, which is provided with a stud, or bolt, on which there is a friction roller. This roller moves back and forth under the curved rocker bar with the motion of the main piston rod and lifts the ends of...
Σελίδα 34 - ... valve for the car to go up. Also open the valve in the drain pipe from the side of the cylinder, and from the lower head of the cylinder, thus allowing the water to drain out of the cylinder. When the cylinder is empty, throw the valve for the car to descend in order to drain the...
Σελίδα 34 - To pack a vertical cylinder piston from the top, run the car to the bottom and close the stop-valve in the supply pipe. Open the air cock at the head of the cylinder and also keep open the valve in the drain pipe from the side of the cylinder long enough to drain the water in the cylinder down to the level of the top of the piston. Now remove the top head of the cylinder, slipping it up the piston rod out of the way and fastening it there. If the piston is not near enough to the top of the cylinder...
Σελίδα 26 - The accumulator used is of the differential type; that is, it has a small cylinder e filled with oil or water in which its ram moves, and above it has a much larger cylinder d filled with compressed air. On the top of the ram of the accumulator is an enlarged piston rod carrying a piston, which fits closely in the air cylinder. From this construction it follows that the pressure per square inch on the ram of the accumulator will be the pressure of the air in the air cylinder per square inch multiplied...
Σελίδα 46 - ... S, S' are connected in series across the armature terminals, forming a shunt circuit to the armature. When the main switch is closed, all the resistance is in series and the pressure across the armature terminals and coils S, S' is very small; consequently, very little current flows through S, S'.
Σελίδα 40 - The starting, stopping, and reversing are controlled by a shipper sheave 5 operated from the car. When the shipper sheave is moved in either direction, a cam moves the rod r back and forth. In the figure the shipper sheave is in the neutral position. R is the reversing switch that connects the motor to the line and controls the direction of rotation of the motor. This switch is operated by the cam c. The shaft s of the switch carries a number of arms, which engage with suitable contacts when the...
Σελίδα 33 - ... should become slack. For this purpose a rod r is placed across and underneath the drum, which rod is attached to the end of a weight-actuated lever that is tripped and closes the clutch C when there is any weight resting on the rod r. Both kinds of slack-cable safeties are extensively used. 63. Fig. 27 shows a worm-geared elevator built by Morse, Williams & Co., Philadelphia, Pennsylvania. In this machine the various requirements are fulfilled by slightly different means than have so far been...