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Monday (2019.6.17) https://bbs.hcbbs.com/thread-2728056-1-1.html 1. In a closed tank containing a medium with a specific gravity of 1.32, if the liquid level is 12 meters above the bottom of the tank, then the pressure at the bottom of the tank is (D). A 155KPa B Higher than 155KPa C Lower than 155KPa D Uncertain 2. At altitudes above 2000 meters, high-altitude motors should be used (Correct – although the standard specifies it for altitudes above 1000 meters). Tuesday (2019.6.18) https://bbs.hcbbs.com/thread-2728443-1-1.html 1. The connection hole for the vibration sensing sensor of the rolling bearing on the bearing housing is not connected to the interior of the bearing housing (correct) ； 2. For a given self-priming pump, when the specific gravity of the medium increases, its self-priming height remains essentially unchanged (incorrect). Wednesday (2019.6.19) https://bbs.hcbbs.com/thread-2729266-1-1.html 1. The self-priming time is an indication of a self-priming pump’s ability to prime itself; the length of this time is determined solely by the pump itself ； (Mistake: the length and diameter of the inlet pipeline also directly affect the self-priming time.) 2. Magnetic oil seals (magnetic seals) belong to mechanical seals (correct; it’s just that the elastic element is the force exerted by permanent magnets). Thursday (2019.6.20) https://bbs.hcbbs.com/thread-2729820-1-1.html 1. For transporting a medium with a specific gravity of 0.8 through pipelines, with a required flow rate of 340 m3/h and an average flow velocity of 3 m/s, the standard pipeline diameter that should be chosen is (200) mm ； 2. Standard M20x1.5 threads made of the same material have a higher tensile strength than M20x2.5 threads. (Correct). Friday (2019.6.21) https://bbs.hcbbs.com/thread-2730370-1-1.html 1. For a double-cylinder, double-acting plunger pump with a cylinder diameter of 50 mm, a stroke length of 260 mm, and a plunger stroke frequency of 75 times per minute, the flow rate of this pump is ((0.5^2/4)*3.14159*2.6*4*75=153.2) L/min, assuming no losses. 2. In coastal areas, there are unsealed water towers used for domestic water supply; the vertical height of the water level in such towers is 22 meters, and the atmospheric pressure in those areas is 101 KPa. The static water pressure at the bottom of the tower is therefore (1000*9.81*22/1000+101=316.8) KPa(A). Saturday (2019.6.22) https://bbs.hcbbs.com/thread-2730822-1-1.html 1. A PID diagram refers to a process flow diagram (incorrectly – a PID diagram refers to a piping and instrumentation diagram) ； 2. In the Plan62 scheme, the external cooling water can enter from above and exit from below (correct). Happy weekend! ! !