German LEISTRITZ pump, LEISTRITZ model, LEISTRITZ price

LEISTRITZ pump is a type of pump that uses the rotation of helical blades to lift water axially in a spiral pattern. It consists of a shaft, helical blades, and a housing. During pumping, the pump is placed obliquely in the water so that the inclination angle of the pump's main shaft is less than that of the helical blades, with the lower end of the blades in contact with the water. When the prime mover drives the screw pump shaft to rotate via a variable speed device, water enters the blades, rises along the spiral flow channel, and is discharged. The structure is simple, manufacturing is easy, flow rate is high, head loss is low, efficiency is high, and maintenance is convenient. However, it has low head and low rotational speed, requiring a variable speed device. It is widely used for irrigation, drainage, and lifting sewage and sludge.

LEISTRITZ Pump Classification

Screw pumps are classified by the number of screws. Single-screw pump: A pump where a single screw rotates in mesh within the internal threaded groove of the pump body. Twin-screw pump: A pump that transports liquid using two mutually meshing screws. Triple-screw pump: A pump that transports liquid using multiple mutually meshing screws. [1) Single-screw pump: This is a single-screw transport pump. Its main working components are an eccentric helical screw (called the rotor) and a screw liner with a double-line helical inner surface (called the stator). Its working principle is that when the motor drives the pump shaft to rotate, the screw rotates around its own axis while simultaneously rolling along the inner surface of the liner, thereby forming sealed chambers within the pump. For each revolution of the screw, the liquid in the sealed chamber advances by one pitch. As the screw continues to rotate, the liquid is pressed from one sealed chamber to another in a spiral manner and finally extruded out of the pump body. The screw pump is a new type of liquid transport machinery, featuring advantages such as simple structure, safe and reliable operation, ease of use and maintenance, continuous and uniform discharge, and stable pressure. 2) Twin-screw and multi-screw: It mainly consists of a liner (pump cylinder) fixed in the pump body, a driving screw inserted into the pump cylinder, and two driven screws meshing with it. The three mutually meshing screws form a sealed chamber for each lead within the pump cylinder, creating a seal between the suction and discharge ports. During operation, since the two driven screws mesh symmetrically with the driving screw on the left and right, the radial forces acting on the driving screw are completely balanced, and the driving screw does not bear bending loads. The radial forces on the driven screws are supported by the pump cylinder liner along their entire length; therefore, no additional bearings are needed at the outer ends, and they basically do not bear bending loads. During operation, an oil film forms between the outer circular surface of the screws and the inner wall of the pump cylinder, preventing direct metal-to-metal contact and significantly reducing wear on the screw tooth surfaces. When the screw pump operates, suction and discharge pressures act on both ends, generating axial thrust on the screws. For small pumps with a pressure difference less than 10 kgf/cm2, thrust bearings can be used. In addition, high-pressure oil is introduced into the bottom of each screw bushing through the central oil hole of the driving screw, generating a balancing thrust at the lower end of the screw opposite to the direction of the axial thrust. Like other positive displacement pumps, if the discharge port of a screw pump is completely blocked, the pressure inside the pump will rise to a level that risks damaging the pump or overloading the motor. Therefore, safety valves must be installed at the suction and discharge ports. The shaft seal of a screw pump usually adopts a mechanical seal, with different forms selected based on the operating pressure.

LEISTRITZ Pump Features

Compared with vane pumps, screw pumps have the following advantages: (1) Low rotational speed (generally 20r/min～90r/min), minimal mechanical wear, and no cavitation. (2) Wide flow channels allow the transport of water containing solids. (3) The pump body structure is semi-open, allowing observation of internal operation. (4) The flow state on the suction side has negligible impact on hydraulic performance; there are no special requirements for the suction sump, foundation excavation depth is shallow, hydraulic structure construction is simple, and civil engineering costs are low. Disadvantages include: (1) Large dimensions and large footprint. (2) Limited by machining conditions, the pump shaft cannot be too long, resulting in low head, generally not exceeding 10m. (3) The height variation between the suction and discharge water levels cannot be too large; otherwise, it will affect work efficiency and increase energy consumption.

LEISTRITZ Pump Selection and Application

Screw pumps are characterized by variable displacement delivery, strong self-priming capability, reversibility, and the ability to handle liquids containing solid particles. In wastewater treatment plants, they are widely used for transporting water, wet sludge, and flocculant solutions. The selection of screw pumps should follow the principles of economy, rationality, and reliability. If inadequate consideration is given during design and model selection, it will cause difficulties in subsequent operation, management, and maintenance. Therefore, selecting a screw pump that meets actual production needs and is rational and reliable not only ensures smooth production operations but also reduces repair costs. 1) Selection of screw pump speed: The flow rate of a screw pump has a linear relationship with its rotational speed. Compared to low-speed screw pumps, high-speed screw pumps can increase flow rate and head, but the power consumption increases significantly. High rotational speeds accelerate wear between the rotor and stator, inevitably causing premature failure of the screw pump. Moreover, high-speed screw pumps have very short rotor and stator lengths, making them highly susceptible to wear, thereby shortening the service life of the screw pump. Reducing the rotational speed via a gearbox or stepless speed regulation mechanism Keep its rotational speed within a reasonable range below three hundred revolutions per minute, can extend the service life several times compared to high-speed screw pumps. The service life can be extended several times. 2) Quality of screw pumps: There are many types of screw pumps. Relatively speaking, Imported screw pumps feature a rational design, high-quality materials, but higher prices, inadequate service in some cases, high spare parts prices, long lead times, which may affect normal production operations. When selecting products, considering their cost-effectiveness, choose low-speed, long-lead, products with high-quality transmission components and long rated service life. 3) Ensure that debris does not enter the pump body: solid debris mixed into wet sludge will damage the rubber stator of the screw pump, so it is important to ensure that debris does not enter the pump chamber, many wastewater treatment plants install crushers before the pump, while others install grating devices or filter screens to prevent debris from entering the screw pump; gratings should be cleaned promptly to avoid clogging. 4) Avoid material interruption: screw pumps must never operate under conditions of material interruption; once this occurs, the rubber stator, due to dry friction, will generate high temperature instantly and burn out, therefore, The crusher is in good condition, Unobstructed grating is one of the necessary conditions for the normal operation of the screw pump, Therefore, Some screw pumps are also equipped with a material-breakage shutdown device on the pump body, When material breakage occurs, Due to the self-priming characteristic of the screw pump, A vacuum will be generated in the cavity, The vacuum device will cause the screw pump to stop operating. 5) Maintain constant outlet pressure: The screw pump is a positive displacement rotary pump, When the outlet end is obstructed, The pressure will gradually rise, To the point of exceeding the predetermined pressure value. At this time, the motor load increases sharply. The load on the relevant parts of the transmission machinery will also exceed the design value, In severe cases, motor burnout and fracture of transmission parts may occur. To avoid damage to the screw pump, A return oil valve is generally installed at the outlet of the screw pump, To stabilize the outlet pressure, And maintain the normal operation of the pump.

Weidou Intelligent Technology professionally sells German LEISTRITZ screw pumps, LEISTRITZ gear pumps, LEISTRITZ diaphragm pumps, LEISTRITZ centrifugal pumps, LEISTRITZ piston pumps, LEISTRITZ vacuum pumps, LEISTRITZ screw pumps, LEISTRITZ submersible pumps, LEISTRITZ peristaltic pumps, LEISTRITZ lubrication pumps, LEISTRITZ vane pumps, LEISTRITZ metering pumps, LEISTRITZ hand pumps, LEISTRITZ drum pumps, LEISTRITZ lobe pumps, LEISTRITZ booster pumps, LEISTRITZ liquid pumps, LEISTRITZ air pumps. Original German imports. Welcome customers to inquire and order.