1. 8 core technical parameters that must be provided for pump inquiry
Technical parameters | Recommended information | Impact on pump selection |
|---|---|---|
Flow (Flow Rate) | m³/h, minimum, normal, maximum flow | Determine the specifications and operating range of the pump |
Head (Total Head) | m, normal and maximum demand | Determine the impeller, number of stages and pump type |
Conveying medium (Liquid) | Name, concentration and composition | Determine the material of the flow-passing parts |
Medium temperature (Temperature) | Normal and maximum temperature, ℃ | Affects seals, bearings and materials |
Density and viscosity | kg/m³, mPa·s and corresponding temperature | Affect performance and power calculation |
Suction conditions (Suction) | Suction pressure, liquid level, NPSHa | Judgment Risk of cavitation |
Working pressure (Pressure) | Suction, outlet and design pressure | Determine the pressure rating |
Power supply parameters (Motor) | Voltage, frequency, protection and explosion-proof level | Determine the motor configuration |
Among them, flow, lift, medium characteristics and suction conditions are important basis for the initial selection of centrifugal pumps. For corrosive, high-temperature, high-viscosity or particle-containing media, detailed media data must also be provided.
2. What parameters need to be added for inquiry of different industrial pumps?
1. Chemical centrifugal pumps and magnetic pumps
When purchasing chemical pumps, the corrosiveness of the medium, solid content, crystallization tendency and whether leakage is allowed should be supplemented. For hazardous, flammable or toxic media, the sealing form and applicable safety requirements should be clearly defined.
Magnetic pumps also need to focus on confirming whether the medium contains particles, whether it is easy to vaporize, and whether dry running is possible to avoid damage to the internal circulation and bearing systems.
2. API 610 petrochemical process pump
Petrochemical projects usually need to clarify the API 610 standard requirements, pump type preferences, design pressure, design temperature and on-site hazardous area classification.
For pump types such as OH2, BB2, BB3, BB5, VS4 and VS6, the installation method, operating pressure, suction conditions and bearing configuration will directly affect the design plan. API 610 is applicable to centrifugal pumps related to the petroleum, petrochemical and natural gas industries. Specific projects should also specify the standard version adopted.
3. Multi-stage pump and boiler feed water pump
In addition to the flow rate and total head, the boiler feed water temperature, inlet pressure, start and stop frequency and continuous operation requirements also need to be provided.
For high-lift multi-stage pumps, the shaft power, NPSH and axial force balance plan at each operating point should be focused on. The number of stages cannot be determined based on the lift alone.
3. Three selection issues that are easily overlooked when inquiring about pump prices
1. The head cannot be simply equated to the outlet pressure
The total head of the pump needs to be determined based on the pressure, elevation and speed head of the suction and discharge ends. For the tank delivery system, pipeline friction loss, valve resistance and liquid level changes should also be considered to avoid oversizing or undersizing.
2. The available NPSH must be confirmed
NPSHa (available NPSH) depends on the actual suction system and cannot be directly replaced by the NPSHr provided by the pump manufacturer.
It is necessary to check the appropriate margin between NPSHa and NPSHr when selecting, especially for high-temperature liquids, low-level storage tanks and long-distance suction pipelines.
3. Don’t just look at the name of the medium when selecting materials
The same chemical medium may have significantly different corrosive effects on materials under different concentrations, temperatures and impurity conditions.
For example, for concentrated sulfuric acid pumps, the suitability of materials cannot be judged solely on the basis of "stainless steel corrosion resistance", but should be evaluated in combination with concentration, temperature, flow rate and material corrosion resistance data.
4. How to prepare a complete pump RFQ in project procurement?
The following is a list of parameters that can be used directly for a preliminary technical inquiry.
Inquiry items | Fill in examples |
|---|---|
Pump usage | Chemical raw material transportation |
Media name | Process liquid, provide ingredient list |
Normal flow | 100 m³/h |
Total lift | 80 m |
Operating temperature | 90℃ |
Liquid density | 1,100 kg/m³ |
Viscosity | 3 mPa·s |
Suction conditions | Provide minimum liquid level and inlet pressure |
Flow-passing material | Wait Manufacturer's confirmation |
Sealing method | Choose according to the risk of the medium |
Motor power supply | 380 V/50 Hz |
Quantity | 2 units |
Project requirements | Provide performance curves, quotations and delivery dates |
Note: The above parameters are only used to display the inquiry form and do not mean that the pump selection has been completed. Actual procurement also needs to verify NPSHa, working pressure, operating range and related safety requirements.
For large-scale engineering projects, it is recommended to provide P&ID flow charts, piping layout diagrams, media safety data sheets (SDS) and project technical specifications at the same time to reduce the number of technical clarifications.
