Reciprocating pump is fluid transfer device that directly supply energy to liquid in the form of pressure energy through the reciprocating motion of pistons/plungers within cylinders. They are the most widely used positive displacement pumps in industrial applications, such as mud pump, pressure test pump, high pressure pump, cementing pump, and injection pump. Whether in oilfield water injection, high pressure cleaning, or drilling platforms, they play an extremely important role and hold an irreplaceable position. But have you ever wondered how a simple reciprocating motion generates stable pressure energy to drive fluid conveyance? Below, we'll introduce the most fundamental reciprocating motion, gradually guiding you toward a thorough understanding of the reciprocating pump's operating principle.   Core Components of Reciprocating Pump 1. Power end: Crankshaft, connecting rod, crosshead, intermediate rod, etc.; 2. Hydraulic end: Piston/plunger, piston seal/plunger seal, shock-resistant pressure gauge, safety valve, etc.; 3. Control valves: Suction valve, discharge valve (typically check valves); 4. Others: Lubrication system, cooling system, etc. Working Principle of Reciprocating Pumps The electric motor drives the pump's crankshaft to rotate via a large and small pulley and a narrow belt. The crankshaft drives the connecting rod, piston or plunger to perform reciprocating motion. When the piston or plunger moves backward, the inlet valve opens, allowing liquid to enter the pump body until the piston or plunger reaches its final position (crankshaft rotates 180°), concluding the suction process. The piston or plunger then begins its forward stroke. During this phase, the liquid within the pump's valve chamber is compressed, increasing pressure. Consequently, the inlet valve closes while the outlet valve opens, allowing the liquid to be expelled through the outlet valve by the piston or plunger. Materials of Reciprocating Pumps 1. Power-end components are predominantly castings, primarily made of materials such as QT450 and QT600. 2. Hydraulic-end components are flow-through parts requiring selection based on customer-provided parameters: Medium characteristics: medium name, specific gravity, viscosity, corrosiveness, toxicity, etc. lParticle diameter and content of solids in the medium. lMedium temperature: (°C) lRequired flow rate lPressure: suction tank pressure, discharge tank pressure. 3. Commonly used materials include but are not limited to the following: 45#, 304, 316L, 2205, 17-4PH, 0Cr17Ni2. Reciprocating Pump Working Cycle 1. Suction Stroke lDuring the suction stroke, the piston or plunger moves backward, creating a low-pressure zone within the cylinder. lThe inlet valve opens due to external fluid pressure, drawing liquid into the pump body. lAs the crankshaft continues to rotate, the piston or plunger gradually moves to its final position, completing the entire suction process. The key to this stage lies in ensuring the sealing integrity of the inlet valve to prevent air ingress or liquid backflow, thereby guaranteeing the pump's operational efficiency and stability. 2. Discharge Stroke lWhen the piston or plunger begins to move forward, the fluid inside the cylinder is compressed, causing the pressure to rise rapidly. lThe inlet valve closes, and the outlet valve opens under pressure. Liquid is expelled from the pump body through the outlet valve and enters the delivery pipeline. This process requires the drain valve to possess excellent pressure resistance and rapid response capabilities to accommodate frequent opening and closing demands under high pressure conditions. Efficient operation throughout the entire working cycle relies on the precise coordination between all components, thereby ensuring continuous and stable fluid delivery. Advantages of Reciprocating Pumps 1. Compatible with virtually any fluid; 2. High efficiency, exceeding 90%; 3. Adaptable to diverse operating conditions; 4. Extended service life; 5. Simple structure for easy maintenance and servicing; Flow Rate and Pressure of Reciprocating Pumps 1. Flow rate is determined by the piston or plunger, stroke length, and rotational speed. 2. Pressure is determined by the pump's power, valve sealing integrity, and discharge resistance. Reciprocating pumps are a type of positive displacement pump, to be, that achieves fluid conveyance through periodic changes in the volume of its working chamber. The mechanical energy from the prime mover is directly converted by the pump into pressure energy for the conveyed fluid. The pump's flow rate depends solely on the change in working chamber volume and the frequency of this change per unit time, and is (theoretically) independent of the discharge pressure. Elephant Machinery specializes in reciprocating piston pump and plunger pump. Designed in compliance with relevant national standards such as GB/T9234-2018, as well as international standards including API 674 Third Edition and ISO 13710:2004, our pumps meet flow and pressure requirements across diverse application fields. We welcome inquiries from professionals in all industries at any time and will provide you with the most professional solutions!