A.face shield
B.a respirator
C.rubber gloves
D.an all purpose gas mask
您可能感興趣的試卷
你可能感興趣的試題
A.lantern rings
B.bearings
C.easing volutes
D.wearing rings
A.packing gland
B.mechanical seals
C.lantern rings
D.wearing rings
A.through a detachable hose connection
B.after passing through an activated charcoal filter
C.after chemical analysis shows it is fit for consumption
D.through a solenoid operated three-way valve
A.worn gland sealing shaft
B.worn wearing rings
C.a bent shaft
D.reversed pump coupling
A.A power end and fluid end
B.A propeller and educator
C.A volute and impeller
D.A turbine and piston
最新試題
Which of the following problems could cause the high pressure cutout switch to shut down the compressor in a refrigeration system?（）
The output volume of a positive fixed displacement pump can be changed only by （）.
The control mode in which the final control element is moved from one of two flexed positions to the other is known as （）.
An increasing head pressure in a refrigeration system, without any corresponding change in the cooling water inlet temperature, would probably be caused by （）.
If you are given the job of adding hydraulic fluid to a mooring winch, and are not certain as to the type of fluid to use, you should （）.
Thermostatic expansion valves can be adjusted for （）.
If the head pressure of a reciprocating refrigeration compressor is excessive, （）.
Which of the following statements is correct concerning heat transfer?（）
The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its （）.
A salinity indicator is used to determine the （）.