How is the maximum water supply capacity of a fire station calculated?
Thread Content
The last edit to this post was made by juncaide on 2011-5-20 at 22:31. I have a question for everyone: The company originally had Fire Station No. 1, which was equipped with 2 fire pumps. The flow rate of each pump was Q=486 m^3/h, the power was P=250 KW, the head per pump was H=120 m, and the pipe diameter was 400 mm. As part of the expansion, a new Fire Station No. 2 was built, equipped with 2 fire pumps. The flow rate of each pump is Q=576 m^3/h, the power is P=345 KW, the head per pump is H=165 m, and the pipe diameter is 400 mm. Then they are connected in parallel to meet production needs. However, the problem that arises in practice is that the power of Fire Pump Station No. 2 is too high, while Fire Station No. 1 is unable to discharge water properly. To address this issue, the company has installed a control system that allows the outlet pressure to be maintained at 1 Mpa. What we want to know now is what the maximum water supply capacity of the entire fire station is ? ? Thank you all, I’ll be online the whole time.
Fire station No. 1, equipped with 2 fire pumps, with a flow rate of Q=486 m^3/h and a power rating of P=250 KW – what is the head? Fire station No. 2, equipped with 3 fire pumps, with a flow rate of Q=576 m^3/h and a power rating of P=345 KW – what is the head? What are the diameter and flow capacity of the fire protection main? If the pump head is the same and the pipe diameter is sufficient, the water supply capacity can reach 2700 cubic meters per hour
Does the original poster have a flowchart? Pipe length, diameter? The pump’s head? Operation mode? PS: The flow rate can be roughly estimated based on the pipe diameter, length, and pressures at the start and end points. For detailed calculations, one should consult a specialist in water supply and drainage. Simulated calculations can also be performed using Pipedrop. The pipe diameters are matched; if the flow rate increases significantly, it would be inappropriate not to modify the main pipe. It needs to be calculated before a decision can be made. “What kind of device is a “balance voltage stabilization system”? If it is a complete set of equipment, there should be a nameplate for reference. As I understand it, the most cost-effective approach is to have at least one frequency converter at Station 2 (to automatically control the outlet water pressure by adjusting the speed of one pump). One drive for multiple units or multiple frequency converters. (Determined by the number of pumps in operation), the water pump is automatically adjusted via PID frequency control based on the outlet pressure.
Look, this power is the sum of several pumps.
Reply to 3# pzhmotor: The known conditions have been updated. Could you please help by explaining the process in more detail? Thank you
The conditions are far from sufficient; you have only provided the parameters listed on the pump’s nameplate, or in other words, the operating parameters at the design point. What is needed are the parameters related to the piping system, such as the length of the pipes, the height difference, the number of fittings, the number of bends, etc. Determining the flow rate actually involves finding the intersection point between the pump’s performance curve (the head-flow rate curve) and the piping system’s curve (the head-flow rate curve). To solve your problem, it is necessary to draw both curves; providing only the parameters for one curve makes it impossible to determine the flow rate. . The idea is actually quite simple; it’s covered in the section on fluid transfer equipment in the principles of chemical engineering, under the topic of pump operating curves. .
Reply to 1# juncaide: Check the operating curve of the pump – the head is around 100 meters. What is its efficiency? Estimate it based on the rated power and flow rate