Teikoku USA Inc. and the Chempump Division offer a wide variety of sealless, leakproof canned motor pumps for general transfer. Motor sizes range from fractional to 200 horsepower and pumping temperatures range from cryogenic to 1000o F. Pumps can be manufactured using many durable materials including steel, stainless steels, Hastelloys, Monels, and even higher grade alloys. Most pumps can be fitted with bearing wear and/or radial and axial position monitoring. Canned Motor Pumps manufactured by Teikoku and Chempump are classified as follows:
Teikoku USA Inc and the Chempump Division offer both internally- and externally-circulated canned motor pumps supplied based on specific pumping application requirements. Both circulation paths offer unique benefits.
Internal Circulation
Canned motor pumps with internal circulation are commonly used for standard transfer applications, when pumping a fluid with a high melt point and the entire pump can be equipped for heat tracing, or with highly toxic or lethal fluids to eliminate the potential leak paths created by an external circulation line and fittings.
> View Circulation Path for Internal Circulation
External Circulation
Canned motor pumps with external circulation are equipped with a connection off the discharge of the pump casing going to either the rear bearing housing or pump casing adapter. The advantage of an external-circulated pump is that the fluid in the recirculation line can be filtered, cooled, and monitored. It is common to place a self-cleaning filter in the discharge flange of the pump to eliminate any particles from coming in contact with the bearings. Heat exchangers can be used to cool the fluid prior to it entering the motor. Flow and pressure detectors can be installed on the circulation line to monitor the condition of the pump.
> View Circulation Path for Standard External Circulation
Split Internal Flow
Combines the advantages of both Internal & External Circulation in one pump design
Teikoku USA Inc. and the Chempump Division offer a number of centrifugal pumps with hydraulics below the smallest ANSI size (1-1/2 x 1 x 6). These pumps offer higher efficiencies, lower motor horsepower and smaller space envelopes than ANSI pumps yet the same design point. The design point will also be closer to the Best Efficiency Point (BEP) of the pump. Recommended Pumps: > Chempump Dynapump > Chempump G Series
Teikoku USA Inc. and the Chempump Division offer a line of self-priming pumps for pumping fluids from underground tanks and for rail/tank truck unloading. Secondary containment, bearing condition monitoring and compact design are all available in our self-priming pumps.
Canned motor pumps can transfer or boost volatile liquids under conditions of low NPSHA by modifying the standard design to permit circulation through the motor section without vaporizing the liquid in the bearings. Two types of modifications are available:
Reverse Circulation:
The internal circulation flow path for a canned motor pump modified for reverse circulation starts at the pump casing and flows to the rear of the pump. After the fluid exits the rear of the pump, it is returned to the suction vessel. The front bearing housing or pump casing adapter is modified to allow for the circulation fluid to enter the motor section. The rear bearing housing has a port for piping back to the suction vessel.
> View Circulation Path for Vertical In-Line Reverse Circulation
Pressurized Circulation:
For pressurized circulation, a standard pump is modified by installing an auxiliary impeller on the rear of the motor shaft to increase the pressure in the motor section while it passes over the bearings. As the circulated fluid leaves the motor section, it is directed behind the impeller where the pressure is close to the discharge pressure. By returning the recirculation liquid to the high pressure area of the pump, the entire motor section or primary containment barrier is “pressurized," preventing the fluid from vaporizing even though it is at a higher temperature than the suction temperature.
Pressurized circulation eliminates the need for piping back to the suction vessel and allows the fluid to be filtered prior to entering the motor cavity.
Centrifugal General Transfer
Teikoku USA Inc. and the Chempump Division offer sealless, leakproof, centrifugal canned motor pumps for general transfer service. We've designed our pumps to be completely sealless in a single unit with no stuffing box, dynamic seals, or packing. Pumped fluids cannot leak out or be contaminated by in-leakage. Most pumps can be provided with a secondary containment mechanism to eliminate any chance of the fluid being pumped from escaping to the environment.
No special tools, foundations, leveling, or alignment are required for installation. Pumps can be mounted in the horizontal or vertical position to make the best use of rotor dynamics or available space.
Many pumps can be provided with bearing wear monitors or rotor position monitoring to allow trending of wear components. Armed with this information the User can plan simple parts replacement long before a costly failure might occur.