1. What is a pump?
A pump is a machine that transports or pressurizes liquid. It transfers the mechanical energy of the prime mover or other external energy to the liquid to increase the liquid energy.
The pump is mainly used to transport liquids such as water, oil, acid-base liquid, emulsion, suspension emulsion and liquid metal, as well as liquids, gas mixtures and liquids containing suspended solids.
Pumps can usually be divided into three types: positive displacement pumps, power pumps and other types of pumps according to working principles. In addition to classification by working principle, it can also be classified and named by other methods.
For example, it can be divided into electric pumps and hydraulic pumps according to the driving method; it can be divided into single-stage pumps and multi-stage pumps according to its structure; it can be divided into boiler feed water pumps and metering pumps according to its use; Water pump, oil pump and mud pump etc.
There is a certain interdependence change relationship between the various performance parameters of the pump, which can be drawn as a curve to represent, called the characteristic curve of the pump, each pump has its own specific characteristic curve.
2. The definition and historical source of the pump:
Machinery that transports or pressurizes liquids. A pump in a broad sense is a machine that transports fluid or pressurizes it, including some machines that transport gas. The pump transfers the mechanical energy of the prime mover or other energy to the liquid to increase the energy of the liquid.
The improvement of water is very important for human life and production. There have been various water-lifting appliances in ancient times, such as chain pumps in Egypt (17th century BC), Chinese cassias (17th century BC), pottery wheels (11th century BC), waterwheels (1st century AD), and 3rd century BC Spiral rods invented by Archimedes in ancient Greece. Around 200 BC, the ancient Greek craftsman Ketesbius invented the most primitive piston pump-the fire pump. As early as 1588, there were records of four-vane sliding vane pumps, and various other rotary pumps appeared in succession. In 1689, D. Papan of France invented a 4-blade impeller volute centrifugal pump. In 1818, centrifugal pumps with radial straight blades, semi-open double suction impellers and volutes appeared in the United States. From 1840 to 1850, H. R. Worthington of the United States invented a piston pump that directly opposes the steam between the pump cylinder and the steam cylinder, marking the formation of a modern piston pump. From 1851 to 1875, multi-stage centrifugal pumps with guide vanes were successively invented, making it possible to develop high-lift centrifugal pumps. Subsequently, various pumps came out one after another. With the application of various advanced technologies, the efficiency of pumps has gradually improved, and the scope of performance and applications have also gradually expanded.
https://www.wxxjyby.com/