Single-screw pump working principle Single-screw pump working principle Characteristics and selection method Single-screw pump is an internal meshing eccentric rotary displacement pump, pump the main components: a single-headed screw rotor and a commonly used elastic material A stator with a double-turn helix made when the rotor makes a planetary revolution about the axis of the stator in the cavity causes a closed wrist formed between the stator to displace along the helix of the rotor; therefore, the medium is continuously, Ground, and the constant volume from the suction port to the extrusion end, based on this feature, single-screw pump is particularly suitable for the following conditions of work. Single Screw Pumps Transfer High Viscosity Media: Depending on the pump size, media with viscosities from 37,000 to 200,000 centipoise can be delivered. Medium containing particles or fibers: The particle diameter can be 30mm (not exceeding rotor eccentricity). The fiber length can be 350mm (equivalent to the pitch of 0.4 rotor). Its content is generally up to 40% of the media pit, the medium if the solid matter is a fine powder, the maximum content of up to 60% or more can also be transported. Requires delivery pressure is stable, the media do not like to destroy the inherent structure, the selection of single screw pump ideal delivery. ◠Selection of pump specifications Single screw pump is based on the nature of the liquid being transported and flow, pressure to determine, and the pump speed by the viscosity and corrosive liquid delivery, as the main parameters to choose, in order to ensure reliable pump run. In this recommendation (Figure II) for reference. Pump design speed for the transport of water or clear water similar non-corrosive liquids allow the maximum speed, in actual use due to the nature of the media and life requirements are different, the choice should generally be lower than the design speed, the high viscosity and medium containing particles , Generally used design speed of 1 / 2-1 / 3 or lower, low speed on the pump wear is beneficial, but after use due to the stator wear and tear flow rate decreased, then the appropriate increase in speed to compensate for the traffic drop is Regular policy. Transmission medium temperature should be -10 ℃ ~ 80 ℃ in special cases up to 120 ℃. The normal pressure of each stage of the pump (one lead of the stator) is 0.6 Mpa, allowing up to 0.8 Mpa in a short period of time (less than 30 minutes), and gradually decreasing the volumetric efficiency at the same output pressure when worn. Pumping water maximum suction is 8 meters, the actual use of recommendations not exceeding 6.5 meters, when pumping high-viscosity media, should be positive pressure inhalation.
The Tape Measure can be rolled up because there is a spring inside the tape measure. When the measuring length is pulled out, the length of the ruler and the spring is actually stretched. Once the measurement is completed, the spring inside the tape measure will automatically contract, and the ruler will follow the action of the spring force. Shrink, so the tape will roll up.
Metric Tape Measure,Rolling Tape Measure,Automatic Tape Measure,Tape Measure Scale
Shangqiu Yusheng Tools co.,Ltd. , https://www.cnystools.com