Recently, a client ask GN questions about the operation of the big size GN Sludge and solids vacuum transfer pump GNSP40B. The client want to know what is the flow rate of the air supply to GN Sludge and solids vacuum pump? No indication of airflow, clients are just looking at the outlet pressure on the main compressor display to increase the air supply flow rate above 20M3/min will make the pump more powerful.
Below is the communications between GN Solids Control and the client.
The client has been testing the vacuum pump to remove soft sand , and noticed the following situation:
1) Suction pressure is reduced when the status turns into loading (On Auto mode )
2) Continues airflow from the discharge while it is sucking.
3) When the section line is extended to 40 m, the efficiency dramatically reduced.
The client want GN Solids Control could clarify the above.
GN Solids Control replied that,
1) It is right that the air flow goes out from the discharge hose while suction. So this moving air will produce high vacuum by the jet pack. That’s the working principle.
2) The minimum requirement for air supply to feed to the 40 pump is 17M3/hour with pressure 0.8 – 0.9 mpa. What is your air supply now? Clients replied that the pressure while sucking is 0.5 mpa and while unloading increase to 0.8 mpa…. Please advise how to increase the supply pressure while sucking?
GN Solids Control asked the client: Do you have an air storage tank between the air compressor and the pump? And what’s the volume of the Air tank? Clients replied that, there is no air storage tank available, the air is going direct to the pump
GN Solids Control expressed that; it will improve the pump performance a lot
to have air flow rate above 20m3/min Minimum needs to be 17m3/min
Also you need to have an air tank to work as buffer tank to connect to the pump.
By doing above you can make the pump working more properly.
3) 40 meters for water is fine but for solids suction is too long. It’s better to keep less than 12 meters. But as the discharge pressure is high. GN Solids Control suggests the client to reduce the suction hose to less than 12m, but they can have much longer hose for discharge.
4) The longer of suction hose, the longer of the suction time should be set. While leaving factory. GN Solids Control sets 10 Seconds for suction and 10 seconds for discharge. Clients can adjust the suction and discharging time according to job site situation.