更多"Gear pumps are （） because they disc"的相关试题:
[单项选择]Gear pumps are （） type because they discharge a near constant amount of liquid regardless of pressure.
A. positive displacement
B. non-positive displacement
C. mixed-flow
D. axial-flow
[单项选择]Gear pumps are of positive displacement type pumps because they discharge a near constant amount of liquid （） pressure.
A. depending on
B. in relative to
C. regardless of
D. because of
[单项选择]Positive displacement, helical gear pumps are well suited for pumping oil because （）
A. stuffing boxes eliminate the leakage problems usually associated with other gear pumps
B. it is not necessary to closely maintain design clearances with this pump
C. they are essentially self-priming and produce a high suction lift
D. these pumps are designed with extreme tooth angled
[单项选择]Under rotary pumps are the gear, （）, cam-and-piston and screw types.
A. reciprocating
B. diffuser
C. turbine
D. vane
[单项选择]The gear and screw pumps are classified as （）.
A. variable stroke pumps
B. multistage pumps
C. positive displacement pumps
D. triple-ported pumps
[单项选择]The gear, screw, and vane pumps are all classified as （）.
A. variable stroke pumps
B. multistage pumps
C. positive displacement pumps
D. triple-ported pumps
[单项选择]The fuel injection pumps on a diesel engine are controlled by a linkage system attached to the （）
A. camshaft
B. crankshaft
C. governor
D. flywheel
[单项选择]I saw your man not operating the winch gear（）gear.
A. in
B. by
C. of
D. against
[单项选择]Hydraulic pumps most commonly used in steering systems are of the （）.
A. lobe type
B. screw type
C. axial piston type
D. volute type
[单项选择]Overgreasing of ball bearings installed on pumps will result in （）.
A. smoother pump operation
B. overheating of the bearing
C. reduced corrosion in the bearing
D. increased pump capacity
[单项选择]Regulations require that cargo pumps in tankers carrying grade D liquid cargo shall be isolatedfrom sources of vapor ignition by（）.
A. cofferdams
B. gastight bulkheads
C. passageways or living quarters
D. general cargo spaces
[单项选择]Cooling water pumps driven by direct reversing diesel engines are usually of the straight impeller vane type pump with a concentric housing to（）
A. facilitate bi-directional operation
B. provide the greatest pump efficiency
C. prevent pump clogging from marine growth
D. prevent cavitation at the pump outlet
[单项选择]Which of the following pumps belongs to centrifugal pump?（）
A. Piston pump
B. Screw pump
C. Diffuser pump
D. Water-ring pump
[单项选择]Centrifugal pumps are popular because they are very simple in construction,and produce smooth, constant, （） discharge.
A. non-pulsating
B. pulsating
C. positive
D. non-positive
[单项选择]Chafing gear（）.
A. reduces and prevents corrosion of standing rigging
B. prevents corrosion of running rigging
C. reduces and prevents wear caused by the rubbing of one object against another
D. protects the body against extreme cold
[单项选择]When fire pumps are used for other than firefighting service，each pipe connecting the other service (except for branch lines used for deck washing) must have a（）.
A. check valve installed in the line
B. shut off valve at a manifold near the pump
C. quick disconnect union within ten feet of the pump
D. regulator in the line set at 125 psi
