Iwaki GM-V Series Chemical Gear Pumps

Iwaki GM-V (GM-15V and GM-25V) is a sealless, magnet-drive internal gear pump with a PVC housing, a CFRETFE rear casing, SiC (silicon carbide) pinion and internal gear and a Si3N4 (silicon nitride) shaft, so the liquid does not touch any metallic part. The GM-15V delivers 3.3 mL/rev (5.9 L/min at 60 Hz) and the GM-25V 12.8 mL/rev (23.0 L/min at 60 Hz) without pulsation, at a maximum pressure of 0.5 MPa (source: Iwaki GM-V catalog CAT-W 0043-07). Mikron Proses (Üsküdar, Istanbul), the Iwaki distributor in Turkey, supplies the GM-V with selection, supply, installation and commissioning.

During operation, the liquid does not come into contact with any metallic part of the pump, and a magnet drive mechanism ensures that no liquid leaks from the pump. The GM-V can therefore handle corrosive liquid chemicals, including acids and alkalis. Because it is pulsation-free and its discharge is proportional to the pump speed (rpm), the manufacturer describes it as suited to metering injection without pulsation.

Two models with ceramic gears

The series has two models according to the size of the pump: GM-15V and GM-25V. The GM-15V moves 3.3 mL per revolution and the GM-25V 12.8 mL; at 60 Hz and 1800 rpm the maximum capacity reaches 5.9 L/min and 23.0 L/min respectively. Both models work up to a maximum pressure of 0.5 MPa. The motor output is 0.4 kW (0.37 kW) for the GM-15V and 0.75 kW for the GM-25V. Connections are JIS10K 15A or Rc 3/8 on the GM-15V and JIS10K 20A or Rc 3/4 on the GM-25V. The pump is close-coupled to its motor, so no intermediate coupling is needed, and the assembly is lightweight and compact.

The model code (for example GM-15VKCV-04FC-S) identifies the pump size (15/25), the body material (V: PVC), the gear material (K: SiC), the bearing material (C: carbon, K: SiC), the O-ring material (V: FKM, E: EPDM), the motor output (04: 0.4 kW, 07: 0.75 kW) and the motor type (F: inverter motor; B: explosion-proof, outdoor type; C: totally enclosed fan-cooled, outdoor type).

Operating conditions and limits

According to the manufacturer, the liquid temperature is 0-50 °C and the viscosity range is 0.5-50 mPa·s; slurry cannot be handled. For liquids with a viscosity of 3 mPa·s or less, the GM-15V has a lower pressure limit for reaching maximum capacity: 0.28 MPa at 60 Hz for 0.5-1 mPa·s and 0.35 MPa for 1-3 mPa·s. The manufacturer recommends installing a 100 mesh strainer and a safety valve at the pump inlet; once the pump is primed, there is no minimum flow requirement. Self-priming up to 1 m in height (when wet) is possible and depends on the liquid and the piping.

The catalog also notes that, because the pump body is PVC, performance may fluctuate with temperature changes, frictional heat on the gear sliding surface and mounting conditions. The pump alone therefore has no fixed-quantity injection capability, and a pulseless dosing system should be introduced where pulseless dosing is required.

Applications

The catalog lists the following uses: automatic injection of coagulant at a constant mixing ratio, pulsation-free metering of paper-making dye and sodium hypochlorite, and process lines where flow and pressure are controlled by the pump speed with an inverter, without bypass piping around a large-flow centrifugal pump. The pump uses no seals or diaphragms, which removes the risk of leaks from the pump.

For other Iwaki pumps, see the Iwaki pump range and the Iwaki magnetic-drive process pumps. Send us your requirement and Mikron Proses can help you with the chemical compatibility check and model selection.