API610 Chemical Pump Selection Process
Complete process of API 610 chemical pump selection
1、 Pre selection preparation
1. Clarify the process requirements
Medium characteristics:

Chemical composition, concentration, temperature

Density, viscosity, vapor pressure

Corrosive, abrasive, toxic

Does it contain solid particles and their particle size distribution

Operating conditions:

Normal/maximum/minimum flow rate (m ³/h)

Normal/maximum/minimum head (m)

Inlet/outlet pressure (MPa)

Operating temperature range (° C)

NPSH Available Value (m)

Operation mode:

Continuous or intermittent operation

Parallel or series operation requirements

Backup pump configuration requirements

2、 API 610 Standard Compliance Confirmation
1. Applicable standard version
Confirm to use the latest version of API 610 (currently version 12)

Clarify the scope of application of the standard:

Petroleum refining

chemical process

Natural gas processing

2. Pump type selection (classified according to API 610)
OH type: cantilever pump

OH1: Rigid coupling, fixed bearing box

OH2: Elastic coupling, adjustable bearing box

OH3: Independent bearing seat

OH4: Magnetic Drive

OH5: Submersible type

OH6: Variable frequency drive

BB type: Two end supported pump

BB1: Axial subdivision

BB2: Radial subdivision

BB3: Multi level

BB4: Double shell

BB5: Bag type

VS type: vertical pipeline pump

3、 Technical selection steps
1. Hydraulic parameter calculation
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1. Specific speed calculation: ns=3.65 × n × √ Q/H ^ (3/4)
(n: RPM, Q: Flow rate m ³/s, H: Head m)

2. Determine the range of pump types:
-Centrifugal pump: ns=20-300
-Mixed flow pump: ns=300-600
-Axial flow pump: ns>600

3. Cavitation allowance verification:
NPSHa ≥ NPSHr+safety margin (usually 0.5-1.0m)
2. Material selection (Appendix H of API 610)
Material of overcurrent components:

Carbon steel (A216 WCB): non corrosive medium

Stainless steel (CF8/CF8M): general corrosive medium

Dual phase steel (CD4MCu/6A): chloride ion corrosion

Hastelloy (C276/C22): Strong corrosive medium

Titanium material: seawater, chlor alkali medium

Sealing ring material:

13% Cr steel+hardening treatment

Sitaili alloy overlay welding

Silicon carbide/tungsten carbide

3. Selection of sealing system (API 682 standard)
Sealing type selection:

Plan 11: Single end face, self flushing

Plan 13: Throttle liner leakage recovery

Plan 21: Cooler+Self flushing

Plan 23: Circulating Cooling

Plan 32: External flushing

Plan 52/53/54: Double end face sealing system

Sealing arrangement:

Arrangement 1: Single seal

Arrangement 2: Non pressure double seal

Arrangement 3: Pressure double seal

4. Bearings and lubrication system
Bearing type:

Radial bearings: cylindrical roller bearings

Thrust bearing: Angular contact ball bearing

Special requirement: tilting pad bearings

Lubrication method:

Oil lubrication: pressure oil system

Oil lubrication: regular replenishment

API 610 requirements: Bearing box oil sight glass, thermometer

4、 Structural design and verification
1. Key points of pump body design
Minimum wall thickness: meets the requirements of API 610 Table 5

Pressure rating: ANSI Class 150/300/600

Flange standard: ASME B16.5 RF or RTJ

Support method: Centerline support (temperature>177 ° C)

2. Shaft and shaft seal design
Minimum shaft diameter: calculated using API 610 formula

Axial deflection limit:<0.05 mm

Runout at the shaft seal:<0.025 mm TIR

3. Critical speed calculation
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1. First critical speed: Nc1>1.3 × working speed
2. Second critical speed: Nc2>2.2 × working speed
3. Horizontal analysis: Avoid resonance frequency
5、 Performance curve confirmation
1. Required performance characteristics
Continuous operation zone: 70% -120% of the Best Efficiency Point (BEP)

Minimum continuous flow rate: 25% -30% of BEP

Maximum allowable flow: 120% -130% of BEP

Dead point head: 110% -120% of BEP head

2. Curve requirements
Head flow curve: continuously rising to the critical point

Power curve: The maximum power is on the right side of BEP

NPSH curve: with sufficient safety margin

6、 Driver selection
1. Motor selection
Power margin: API 610 Table 8 requirements

≤ 22 kW: minimum 15% margin

22-55 kW: minimum 10% margin

55 kW: Minimum margin of 5%

Protection level: IP55/IP56 (outdoor)

Insulation level: F level (temperature rise assessed according to B level)

2. Transmission mode
Direct connection: elastic coupling

Equipped with variable speed: hydraulic coupling/VFD

API Requirement: API 671 (Coupling Standard)

7、 Auxiliary system configuration
1. Cooling system
Cooling water requirements: Appendix D of API 610

Calculation of heat exchange area

Material selection (stainless steel/carbon steel)

2. Monitoring instruments
Required instruments:

Bearing temperature sensor (dual)

Vibration probe (XYZ direction)

Pressure gauge (inlet/outlet)

Flow meter (if required)

API standard requirements:

API 670: Vibration Monitoring System

Temperature alarm/shutdown setting

8、 Document and technical review
1. Suppliers are required to provide documents
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1. Data Sheet (Appendix A of API 610)
2. Performance curve (measured data)
3. Material Certification Documents (MTC)
4. Manufacturing Data Report (MDR)
5. Assembly drawings and sectional drawings
6. Installation and Maintenance Manual
7. Quality Control Plan
8. Test Inspection Plan (ITP)
2. Factory testing witness
Hydraulic performance test: compliant with ISO 9906 Grade 1

NPSH test: Confirm necessary cavitation allowance

Mechanical operation test: more than 4 hours

Special experiment:

Rotor dynamic balancing (ISO 1940 G2.5)

Mechanical vibration testing (API 610 standard)

Auxiliary system function testing

9、 Selection decision matrix
Remarks on the Weights and Scoring Standards for Evaluation Projects
Technical compliance 30% API standard fully complies with one vote veto item
Operating efficiency 20% BEP efficiency value comparison affects energy consumption cost
Reliability 25% MTBF historical data key assessment items
Total cost of ownership 15% Initial investment+maintenance cost 10-year cycle
Delivery time of 5% to meet project schedule
5% local support capability for technical services
10、 Key points of risk management
1. Technical risk control
Reserved margin for medium variation

Extreme working condition simulation analysis

Preparation of backup plan

2. Business risk avoidance
Clearly define the warranty period (usually 12-18 months)

Confirmation of availability of spare parts

Consideration of technology upgrade path

11、 Application of digital selection tools
1. Selection of software usage
Manufacturer selection software

Third party simulation tools (such as Pump Flo)

Online selection platform

2. Trends in intelligent selection
Big data matching historical cases

AI assisted material selection

Performance prediction of digital twins

Selection Process Checklist
Process data is complete and accurate

API standard version confirmation

Reasonable selection of pump type

Material selection suitable medium

The sealing system is safe and reliable

The performance curve meets the requirements

The driver is matched correctly

Complete monitoring instruments

Complete testing plan

Complete technical documents

Through the above systematic process, it can be ensured that the selection of API 610 chemical pumps meets both international standards and actual process requirements, achieving the goals of safe, reliable, and economical operation. It is recommended to organize multi-party technical reviews at key steps, especially for applications involving high-risk media and harsh working conditions.