Power Energy Gulf supplies canned motor pumps for refineries, petrochemical plants, gas processing and chemical facilities in Saudi Arabia and the GCC. A canned motor pump is a sealless design with no shaft seal to leak, which makes it the pump of choice for toxic, flammable and volatile liquids that must not escape to the plant or the atmosphere.
How a Canned Motor Pump Works
The motor and the pump share one sealed casing. A thin metal sleeve, called the can, separates the motor windings from the pumped liquid. A small stream of that liquid cools the motor and lubricates the bearings, so no external lubrication or cooling fan is needed. With no coupling and no shaft seal, there is no alignment to maintain and no seal flush system to run.
Why Plants Choose Canned Motor Pumps
- Leak-free containment. No mechanical seal means no seal leak. This helps plants meet emission limits and protect people on site.
- Lower VOC emissions. Seal leaks are a common source of fugitive VOC and benzene emissions. See our VOC removal and emission control services.
- Handles high pressure and temperature. The motor sits inside the pressure boundary, so these pumps suit severe hydrocarbon and heat-transfer duties when specified correctly.
- Less maintenance. No seal changes, no coupling and no alignment.
- Quiet and compact. One integrated unit with no fan.
Typical Applications
- Benzene, toluene and other aromatics, including BTEX streams
- Toxic, carcinogenic, corrosive and volatile chemicals
- Refrigerants, ammonia and liquefied gases
- Heat transfer oils and hot oil systems
- Hydrocarbon process circulation and transfer
- Tank and tanker unloading of hazardous liquids
- Reactive and high-vapor-pressure liquids
Standards and Selection
For refinery, petrochemical and gas service, sealless pumps are normally specified to API 685, the counterpart of API 610 for sealed pumps. Selection depends on liquid properties, temperature, pressure, NPSH available, viscosity, the hazardous area classification and the required monitoring, such as bearing wear detection. We help you work through the datasheet and match the pump to the duty.
Limits to Know About
- Canned pumps must not run dry, because the liquid lubricates the bearings.
- Abrasive solids wear the bearings, so slurry duties need a specific design.
- The can adds some electrical loss, so efficiency is a little lower than a conventional motor.
- Higher initial cost than a sealed pump, offset by lower maintenance and no seal leakage.
Sealless Pumps: Canned Motor and Magnetic Drive
Sealless pumps, also called seal-less, leak-free, zero-leakage or hermetic pumps, come in two main designs. Canned motor pumps put the motor inside the pump casing behind a thin sleeve. Magnetic drive pumps keep a standard motor outside and transmit torque through a magnetic coupling. Both remove the shaft seal, the part that leaks in conventional pumps. We help you choose between them for your liquid, pressure and temperature. See canned motor vs magnetic drive pumps.
Related Products and Services
See our centrifugal pumps, AODD pumps and industrial equipment pages. For site work, see our tank cleaning and flushing services.
Frequently Asked Questions
What is a canned motor pump?
A canned motor pump is a sealless centrifugal pump where the motor and pump form one sealed unit. A thin metal sleeve, the can, separates the motor windings from the pumped liquid, so there is no shaft seal that can leak. The pumped liquid cools the motor and lubricates the bearings.
What is the difference between a canned motor pump and a magnetic drive pump?
Both are sealless. A magnetic drive pump keeps a standard motor outside and transmits torque through a magnetic coupling and containment shell. A canned motor pump puts the motor rotor inside the pressure boundary, so there is no coupling to decouple. Canned pumps are often chosen for higher pressure, higher temperature and hazardous hydrocarbon duties.
Can a canned motor pump run dry?
No. The bearings depend on the pumped liquid for lubrication, so running dry damages them. Good installations use monitoring for bearing wear, flow and temperature to protect the pump.
Which liquids suit canned motor pumps?
Toxic, flammable, volatile, corrosive or carcinogenic liquids where a seal leak is not acceptable, such as benzene and other hydrocarbons, solvents, ammonia, liquefied gases and heat transfer oils. They are less suited to liquids with abrasive solids unless a slurry design is used.
What standard applies to canned motor pumps?
API 685 is the industry specification for sealless centrifugal pumps, covering canned motor and magnetic drive pumps, in refinery, petrochemical and gas service. It is the counterpart of API 610 for sealed pumps.
What do you need to recommend a canned motor pump?
Send us the liquid and its properties (specific gravity, viscosity, vapor pressure), operating temperature, flow and head, suction conditions (NPSH available), the hazardous area classification and any datasheet or API requirements.
What are sealless pumps?
Sealless pumps, also called seal-less, leak-free or hermetic pumps, are centrifugal pumps with no shaft seal. The two main types are canned motor pumps and magnetic drive pumps. They are used for toxic, flammable and volatile liquids where leakage is not acceptable.
Do you supply magnetic drive pumps as well?
We supply sealless pumps for hazardous duties, including canned motor pumps. Send us the liquid and operating conditions and we will recommend the right sealless design, canned motor or magnetic drive.
Get a Response Within 24 Hours
Send us the liquid, temperature, flow, head and area classification. Call or WhatsApp +966 56 278 9535 or email sales@powerenergy.com.co. Power Energy is based in Jubail Industrial City and supplies industrial customers across Saudi Arabia and the GCC.