Magnetic seal gear pumps – TGMAG series
SPX Johnson TG MAG gear pumps are seal-less gear pumps for low or high viscosity liquids that are corrosive, toxic, aggressive, or expensive. Total confinement of the liquid inside the pump is achieved through a hermetically sealed system that isolates the liquid from the surrounding environment. This design ensures clean and safe operation without leakage of the pumped medium. Magnetically driven pumps are therefore not only environmentally friendly, but also contribute to improved safety in chemical and processing plant environments, and are also compliant with the ATEX directive. This series has a wide selection of material designs and additional options, such as heating jackets, relief valves, or temperature sensors.
TopGear Mag gear pumps can operate in the chemical, petrochemical, and machine manufacturing industries.
FEATURES & BENEFITS
FAST FACTS
SPX Johnson TG MAG gear pumps are seal-less gear pumps for low or high viscosity liquids that are corrosive, toxic, aggressive, or expensive. Total confinement of the liquid inside the pump is achieved through a hermetically sealed system that isolates the liquid from the surrounding environment. This design ensures clean and safe operation without leakage of the pumped medium. Magnetically driven pumps are therefore not only environmentally friendly, but also contribute to improved safety in chemical and processing plant environments, and are also compliant with the ATEX directive. This series has a wide selection of material designs and additional options, such as heating jackets, relief valves, or temperature sensors.
TopGear Mag gear pumps can operate in the chemical, petrochemical, and machine manufacturing industries.
| Pump capacity: | 80 m3/h | |
| Max. rotational speed: | 1450 rpm | |
| Max. discharge pressure: | 16 bar | |
| Temperature: | 260 °C | |
| Viscosity: | 10,000 mPa·s | |
| Max size of solids: | 150 µm | |
| Impeller type: | gear, made of nitrided carbon steel or stainless steel | |
| Pump materialss: | grey cast iron or AISI316 stainless steel | |
| Insulating jacket: | Hastelloy C4 | |
| Magnets: | SmCo (standard) good chemical and temperature resistance up to 260 °C NdFeB (optional) for applications requiring higher torque – temp. limit to 120 °C |
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| Elastomer materials: | FPM, PTFE other materials on request |
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| Application example | |
| Toxic and hazardous liquids | Phenols, solvents, isocyanates, sodium hydroxides, epoxy resins, paints, adhesives, inks, fuel additives, corrosive solutions, sugar solutions, oils, bitumens, alcohols and other crystallizing or hardening liquids. |
The TopGear (TG) series combines robust construction with small or large clearances and a unique tooth profile on the active gear. TG MAG series pumps are seal-less internal gear pumps designed for low or high viscosity liquids that are corrosive, toxic, aggressive, or expensive. This series also offers a wide selection of material designs and additional options, such as heating jackets, relief valves, or temperature sensors.
TopGear MAG pumps are equipped with a unique forced circulation and cooling system. This is a patented, integrated circulation system located in the intermediate cover. It guarantees cooling and lubrication of the magnetic coupling and sleeve regardless of operating pressure or liquid viscosity. Complete enclosure of the liquid inside the pump is achieved thanks to a hermetically sealed system that isolates the liquid from the surrounding environment. This eliminates the need for shaft seals and the associated wear and leakage that would normally occur. This design ensures clean and safe operation. Magnetically driven pumps are therefore not only environmentally friendly, but also contribute to improved safety in chemical and processing plant environments. TG Mag series pumps also comply with the ATEX directive.

The rotor and pinion mesh together as they rotate. This creates sealed chambers with variable volume, resulting in a vacuum that forces the medium to flow into these spaces. The liquid is transported in the chambers from the suction side to the discharge side. The spaces are separated by an element that prevents the liquid from returning to the suction side. The medium is pumped to the discharge side as a result of the decreasing volume of the inter-tooth spaces.
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Pump housing with integrated feet and line connections
The pump housing can remain installed in the piping system during inspection and repair of the rotors and shaft seal. |
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Front access module
The entire front (gear, cover, and gear stub) can be removed for easy internal inspection and repair. |
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Rear access module
The rotor with shaft, intermediate housing with rotor bearing, shaft seal and bearing bracket can be removed for easy inspection, repair and shaft seal replacement. |
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Top-mounted relief valve
The pre-assembled and pre-set overpressure relief valve can be removed for inspection, repair and if the direction of rotation or pressure needs to be changed. |

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1. Pump Casing
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| Front Access Module
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2. Cover with Gear Pin
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“S” or “T” type heating jacket mounted on the cover (optional)
Additional front cover with heating jacket with several types of connections:
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3. Gear with Sleeve
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| Rear Access Module
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4. Impeller and Pump Shaft
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5. Bearing
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6. Bearing Bracket
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7. Magnetic Coupling
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8. Intermediate Cover
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“S” Type Heating Jacket Mounted on the Cover
Steam-powered version with threaded connections.
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“T” Type Heating Jacket Mounted on the Cover
Thermal oil-powered version with flanged connections.
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Gear Shaft Cover (available only with the “T” type heating jacket option)
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Relief Valve
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PT100 Temperature Sensor
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The relief valves used in the TG Mag series are spring-loaded valves that open rapidly when the operating pressure rises to the set pressure value, which is pre-set by the spring. These valves limit the pressure difference (∆p) (or working pressure) between the suction and discharge, not the maximum pressure in the system. If the liquid cannot escape when the discharge side of the pump is blocked, overpressure can cause serious damage to the pump. The relief valve provides an escape route, directing the media back to the suction side after a certain pressure level is reached. An open relief valve signals that the system is not working properly.
| Pump capacity: | 80 m3/h | |
| Max. rotational speed: | 1450 rpm | |
| Max. discharge pressure: | 16 bar | |
| Temperature: | 260 °C | |
| Viscosity: | 10,000 mPa·s | |
| Max size of solids: | 150 µm | |
| Impeller type: | gear, made of nitrided carbon steel or stainless steel | |
| Pump materialss: | grey cast iron or AISI316 stainless steel | |
| Insulating jacket: | Hastelloy C4 | |
| Magnets: | SmCo (standard) good chemical and temperature resistance up to 260 °C NdFeB (optional) for applications requiring higher torque – temp. limit to 120 °C |
|
| Elastomer materials: | FPM, PTFE other materials on request |
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