I would like to ask about whether a piston rotary pump requires barring, as well as issues related to starting and stopping it

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We have several HZB-type piston rotor pumps from Huanuo here. Today, our equipment supervisor said that piston rotor pumps do not require turning. However, the information I found online states that before starting the pump, all the inlet and outlet valves in the pipeline should be opened; once the medium flows into the pump chamber and turning the pump by hand causes no abnormalities, it can be started briefly to verify its rotation direction and the flow of the medium. Only after that can the pump be operated on a full scale, as operating it without any medium is strictly prohibited. ” And “after the pump has been out of use for an extended period of time, before turning it on, the coupling should be rotated by hand; there should be some resistance, but it should still be possible to rotate it freely with even force.” Also pay attention to checking for any grinding noises or foreign objects inside the pump. ” Doesn’t that mean we need to turn the crank? May I ask, does a rotor pump really not require turning? There are also issues related to the starting and stopping of rotor pumps. I have here some information provided by the manufacturer, as well as some information I found online; I’ve extracted excerpts from it. Please take a look and see if there are any contradictions between these two sets of information Manufacturer’s instructions: (1) Before starting the pump for the first time, it is necessary to fill the pump chamber and the inlet pipelines with the medium, so that both the pump chamber and the pipelines are completely filled with it, thereby preventing damage to the rotor and seals ； (2) Before starting the pump, all the inlet and outlet valves must be opened to prevent excessive vibration or high pressure resulting from sudden startup, which could damage the pump and its seals ； (3) The inlet and outlet valves must not be closed while the pump is running; they can be closed only after the pump has stopped. When starting the pump again, make sure to fully open the inlet and outlet valves, as the pipes are already under pressure at that point, to prevent damage to the pump. Online information: (1) Close the gate valve on the outlet pipeline, as well as the outlet pressure gauge and inlet vacuum gauge. (2) Start the motor intermittently to check whether its rotation direction is correct. (3) Start the motor; once the HZB type piston rotor pump is operating properly, open the outlet pressure gauge and the inlet vacuum pump. Once an appropriate pressure is indicated, gradually open the gate valve, while also checking the motor load. (4) To stop using the HZB type piston rotor pump, first close the gate valve and pressure gauge, then shut down the motor. Please take a look – do the explanations in the upper and lower sections contradict each other regarding whether it should be turned on or off alternately?