Nikkiso's canned motor pumps are characterized by their deep-rooted technological foundation as an industry pioneer and their extensive experience in handling extremely challenging conditions (such as high-temperature sulfur and strong acids). While Teikoku Pumps is known for its comprehensive and robust capabilities, Nikkiso is more representative in highly specialized, niche applications.

Core Characteristics: Technological Origins and High-End Applications

We can understand the characteristics of Nikkiso canned motor pumps from three aspects: technological origins, ability to handle extreme conditions, and market position.

Characteristics Dimensions | Core Characteristics | Brief Description and Technological Highlights

Technological Origins and Industry Position | Global Technological Pioneer Nikkiso Corporation is a globally recognized pioneer and leader in the canned motor pump field. Its profound technological foundation serves as a benchmark for the industry.

Patents and Innovation | As an industry pioneer, Nikkiso possesses numerous fundamental patents. Addressing the pain points of traditional canned motor pumps (such as bearing life and inability to transport liquids containing particulates), it has unique improved patented designs. For example, it uses oil-lubricated rolling bearings instead of traditional media-lubricated sliding bearings, significantly improving bearing life and reliability.

Extreme Operating Condition Capability: Demonstrates exceptional performance in extreme temperature environments, particularly with ultra-high/ultra-low temperature media. As early as 1998, there was a proven track record of successfully transporting liquid sulfur (sulfur-to-acid) using Nikkiso's high-melting-point canned pumps, proving its unique technology in handling high-temperature, easily solidifying media. It is equally capable of handling ultra-low temperature LNG and high-temperature heat transfer oils.

Special Chemical Media: Possesses an excellent reputation for transporting highly corrosive, extremely toxic, high-purity, or valuable chemicals, such as sulfuric acid and caprolactam, and is the designated choice for demanding conditions. Shanghai Nikkiso Canned Pumps Co., Ltd. has been selected as a winning or successful supplier in several large-scale national chemical projects (such as Shenhua Ningxia Coal-to-Oil and Fujian Gulei Ethylene Project), fully demonstrating the reliability and market acceptance of its products in core chemical plants.

High Pressure and High Temperature: Designed to withstand combinations of extremely high pressure and temperature, suitable for demanding processes such as hydrogenation and cracking.

Applications of Canned Shielded Pumps in Refineries

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In refineries, the application of canned shielded pumps mainly revolves around their core advantage of zero leakage, used to handle harsh media such as high temperature, high pressure, flammable and explosive substances, and toxic and harmful substances. They have become indispensable equipment in oil refining units, especially in key processes such as hydrotreating and desulfurization.

Core Application Scenarios and Key Technical Parameters

Canned shielded pumps are widely used in refineries, from heavy oil hydrotreating to the transportation of light components. Here are some key application scenarios for it in refineries:

Application Unit/Scenario Typical Medium Key Operating Parameters (Temperature/Pressure) Pump Characteristics and Requirements Actual Cases and Significance

Hydrogenation Unit (e.g., diesel, heavy wax oil hydrogenation) Heavy wax oil, diesel, etc. High temperature (e.g., reactor inlet 15.65MPa) High-temperature separation type, with heat shield and external heat exchanger, hydrogen medium needs to be considered. Domestically produced high-temperature and high-pressure shielded pump successfully applied, completed a full production cycle after modification, bearings showed no significant damage for 3 years.

Coal-to-Oil/Coal Chemical Industry Oil-coal slurry, BDO (1,4-Butanediol) Design temperature 450℃, design pressure 20MPa High-pressure chemical shielded pump, needs to overcome challenges such as high head and low specific speed hydraulic design. Dongfang Electric's independently developed BDO circulating liquid pump has energy consumption more than 10% lower than similar products, filling a domestic gap.

Sulfur Recovery/Acidic Water Treatment Sulfur-containing wastewater, methanol wastewater Temperature 80~175℃, pressure 0~2MPa Horizontal pump, needs to have wear resistance and corrosion resistance. Sinopec Purification Plant's Hazard Mitigation Project Procures Canned Shielded Pumps for Methanol Wastewater Treatment

Aromatics Extraction Units, Aromatic Solvents: The specific process depends on the aromatics solvent; leak-free operation is a fundamental requirement. Canned shielded pumps have mature applications in similar units.
Isocyanate (MDI) Production: MDI raw materials and intermediates, high temperature and high pressure, single-stage hydraulic design, molded coil stator, etc. Dongfang Electric's independently developed canned shielded pumps were exported to Europe for the first time for MDI unit expansion.

Why its Technological Advantages Meet Refining Needs: Refinery conditions can typically be summarized as "high temperature, high pressure, flammable, and toxic," and the design of canned shielded pumps precisely addresses these challenges:

Intrinsically Safe, Leak-Free: For the large quantities of flammable and explosive (such as hydrogen and oil/gas) and toxic and harmful (such as hydrogen sulfide and benzene compounds) media in refineries, canned shielded pumps employ a statically sealed structure, eliminating leakage points by design, making them an ideal choice for ensuring personnel and production safety.

Handling Extreme Operating Conditions: As shown in the table, high temperatures (e.g., 450°C oil-coal slurry) and high pressures (e.g., nearly 16MPa hydrogenation units) in refining processes pose significant challenges to equipment. Canned motor pumps can meet these requirements through designs such as heat shields, auxiliary circulation systems, and special materials.

Suitable for High-Value or High-Purity Media: When transporting fine chemical products or catalysts such as BDO, any leakage can cause economic losses or affect product quality. The completely enclosed structure of canned motor pumps ensures zero leakage of the media, maintaining its purity.

Considerations and Improvements When Selecting Canned Motor Pumps for Refineries: Based on practical application experience, several aspects require special attention when selecting and operating canned motor pumps in refineries:

Preheating and Operation: After initial commissioning or maintenance under high-temperature conditions, the heating rate must be strictly controlled (e.g., ≤40°C/h), and measures such as installing disc springs on critical flanges should be taken to prevent leakage due to thermal expansion and contraction.

Condition Monitoring: To address potential issues such as decreased winding insulation and sudden shaft displacement, insulation should be switched on and tested periodically (e.g., every two months). Critical pumps should be equipped with shaft displacement and bearing wear monitoring devices. Nitrogen sealing of the motor wiring cavity should be considered to isolate humid air and ensure reliable insulation.

Exhaust Design: To avoid the inconvenience of manual venting, it is recommended to prioritize self-venting canned motor pumps, or install automatic exhaust valves at high points on high-temperature pumps to improve operational convenience.

Summary: In conclusion, canned motor pumps, due to their zero leakage and high reliability, are mainly used in refineries for high-temperature, high-pressure, and demanding media applications such as hydrogenation, coal chemical processing, and sulfur recovery. With continuous technological breakthroughs from domestic manufacturers such as Dongfang Electric and Dalian Huanyou, the localization rate and performance of canned motor pumps are rapidly improving, providing a solid equipment guarantee for safe, green, and efficient production in the refining industry.

Are you selecting a pump for a specific hydrogenation project (such as diesel hydrogenation or wax oil hydrogenation), or is it involving special media such as high-temperature slurry? Tell me your specific process parameters, and I can help you further analyze the applicable canned motor pump types and key considerations.