One of the essential pieces of equipment for fluid transportation in industrial sectors like chemical engineering, oil refining, and energy is the centrifugal pump. With 30 years of experience in the field, Yantai Longgang Pump Industry Co., Ltd. has a thorough understanding of the needs of its clients and has compiled this “Practical Guide to Selecting Chemical Centrifugal Pumps” to help you match the equipment precisely and optimize the production process.

Selecting the Appropriate Pump Type: Scenarios Determine the Model

• Atmospheric and Vacuum Distillation Units in Oil Refineries: The API OH2 type cantilever pump is recommended. It has a compact structure and can withstand high pressure, making it suitable for continuous and high-intensity operations.
• Fluid Catalytic Cracking Units: The BB5 type multi-stage pump is the recommended choice because it can deliver a very high head to satisfy the demands of high-pressure transportation.
• Oil Transportation: The BB3 type double-suction pump is adopted. Its large flow design significantly improves the transportation efficiency.

Industry Standard References:

Chinese projects should at least fulfill the GB/T 5656 standard. For particular media, extra anti-corrosion or high-temperature resistance certificates are required.

Overseas projects need to conform with the API 610 standard to ensure international compatibility.

Calculation of Key Parameters: Flow Rate, Head, and Medium Specific Gravity

Flow Rate (Q)

Add a margin of 10%-15% to the actual required flow rate. For example, if the required flow rate is 100 m³/h, select a chemical centrifugal pump with a flow rate of 110-115 m³/h.

The insufficient flow rate or excessive redundancy can be avoided in this way, achieving a balance between efficiency and economy.

Head (H)

Calculation formula: Total head = height difference + pipeline resistance + equipment pressure.

The pipeline resistance needs to be provided by the process team. It is recommended to add a safety margin of 5 meters to the final head.

Medium Specific Gravity

Oil products typically have a specific gravity of 0.7 to 0.9, while heavy oil can have a specific gravity of 0.95.

Precise calculation is required to avoid overload because the specific gravity directly affects the configuration of the motor power.

Checking Cavitation Issues: Avoiding Impeller Corrosion and Vibration

Cavitation is the “invisible killer” of chemical centrifugal pumps, and in order to prevent impeller corrosion, performance degradation, and vibration failures due to the collapse of bubbles, it is necessary to check the device’s Net Positive Suction Head Available (NPSH) to make sure that the minimum pressure inside the pump is higher than the saturated vapor pressure of the liquid.

Simple judgment approach: The inlet pressure of the pump should be greater than the vaporization pressure of the medium. A safety margin of more than 0.6 meters is recommended.

Case:

Cavitation is more likely to occur in the feed pumps of fluid catalytic cracking systems. Such pumps should have an NPSHa of at least 8 meters. Reducing the rotational speed or switching to a pump type with lower cavitation characteristics can alleviate the issue if the margin is insufficient.

Handling of Special Media: High Temperature, Corrosion, and Solid Particles

• High-Temperature Media (≥200°C)

Select a pump with a cooling system and match it with a high-temperature mechanical seal. Besides, the pump body material should also be made of high-temperature resistant materials, such as C-6, A-7 and above.

For lava pumps with even higher temperatures, when the medium temperature exceeds 300°C, materials of N6 and above should be used.

• Media Containing Solid Particles (such as catalytic slurry)

A design of an open impeller can reduce the risk of blockage. A sealing flushing scheme should also be equipped to extend the service life of the centrifugal pump.

• Corrosive Media

For sulfur-containing oil products, duplex stainless steel materials should be used. For acid and alkali media, fluorine-lined pumps are recommended.

Practical Selection Suggestions

• Seal Selection

Common media: A single-end face mechanical seal is sufficient.

Hazardous media (toxic, flammable): A double-end face seal (API Plan 53) must be used.

• Motor Configuration

Select explosion-proof motors in explosion-proof areas, and reserve a power margin of 10%.

• Key Points of Cooperation with the Manufacturer

Complete process parameters, including the most demanding working conditions, must be provided when looking for a pump manufacturer. Professional manufacturers with API certification (for instance, Longgang Pump Industry) should be prioritized for oil refinery pumps due to their safety, equipment dependability, and after-sales support.

Why Choose Longgang Pump Industry?

As a global supplier of centrifugal pumps, we promise:

✅ API-compliant OH, BB, and VS series centrifugal pumps.

✅ Customized solutions covering complex working conditions, including high temperature, corrosion, and high viscosity.

✅ 30 years of technical accumulation, serving more than 500 enterprises worldwide, and a quick response to customer needs.

Get a quote and selection consultation from us today!