Star Positive Displacement Internal Gear Pump
These heavy-duty STAR Series pumps have packed-type or mechanical seal construction as standard for shaft protection and prevention of leakage. Packed pumps have extra-deep stuffing box. The rotary-type mechanical seal works with pressure, although it can works against.
It’s a self-adjusting and no leak mechanical seal and, thanks to its sealing method, prevents scoring of the pump drive shaft. STAR Series mechanical seal pumps are made for viscosities up to 15,000 SSU/ 3.300 cSt: for higher viscosities are available other seals on demand, contact the manufacturer for advice.
STAR pumps are suitable for pumping liquids of any viscosity. Solids cannot be handled, but the pumps can cope with abrasive
particles. Every day, STAR pumps are handling hundreds of different liquids, such as:
- Chemicals products
- Petroleum products
- Soap and detergents
- Paint and ink
- High temperature liquids
STAR pumps are internal gear positive displacement rotary pumps. The flow is generated by two gears: the rotor and idler, one inside the other, divided by a crescent. As the gears rotate, liquid is drawn into the spaces created between the gears and the crescent. When the gears mesh, the liquid is forced out of the pump. The result are a smooth flow of liquid and high capacity combined with compact size.
- Constant capacity, directly proportional to the rotation speed and virtually independent of the pressure.
- Smooth flow, without pulsations or pressure peaks which could cause vibrations in the pipework.
- Versatility. Simply by adjusting the axial position of the rotor, the same pump can handle water-thin liquids or high viscosity liquids such as bitumen, molasses, resins, polymers, etc.
- Reversibility. By inverting the direction of rotation the flow of liquid is reversed. Full performance is available in either direction of flow.
- Revolving casing. STAR Series features as standard the possibility to rotate in any position (except STAR 140 size, which cannot turn to 180° position) the casing to cope with piping. In any pump, the relief valve has to point to suction port.
- Self-priming. The high vacuum created by the pump gets rapid self-priming at the maximum height accordingly with the physical characteristics of the pumped liquid (temperature, vapor pressure, viscosity, etc.).
- Simplicity. Only two moving parts: the rotor and idler gears, and only one shaft seal.
- Rugged, heavy duty construction. Low rotor peripheral speed. External pedestal bearing housing with oversize ball bearing to take axial and radial loads.
- Conformity to API 676. Detailed list of exceptions available on request.
- Low rate of wear. The number of teeth on the rotor and idler are not multiples one of the other. This means that wear is evenly distributed over the gears since each tooth on one gear touches each tooth on the other gear the same number of times.
- Wear adjustment system. The wear on the front of the rotor can be compensated for by adjusting the axial position of the rotor. This ensures constant performance even with considerable wear.
- Simple, minimal maintenance. Inspection and regulation can be carried out without removing the pump, piping or drive.
- Positive-lock thrust control. STAR Series has a positive-lock thrust control to position accurately rotor and shaft.
- Interchangeability. The modular design makes it possible to replace components with others in alternative materials or with different characteristics. For example, several shaft sealing systems are available, and jacketed covers can be fitted instead of the standard components.
- Preheating. Heating chamber mounted on the cover and, for Mod. 075, 100, 140, 420 can be combined also with Relief Valve.
- By-pass relief valve. This is mounted as standard in each pump and it’s set to 50 lbs/3,5 bar unless specified differently when ordering. The valve guarantees a protection against overpressure by-passing liquid.