In a previous article ‘什么是积极的位移泵？’we gave a high-level overview of different types of Positive Displacement Pumps. In this article, we will focus on Reciprocating Positive Displacement Pumps – how they work, advantages/disadvantages, and common applications in which they are used.
与使用叶轮的离心泵相反，用于供应正位移的机械组件是活塞，柱塞或隔膜。基本功能是使用这些往复组件之一，通过增加或减少内部压力和压力来将液体移动到圆柱体内。根据设计的不同，可以有多个往复式组件。
To gain a more in-depth understanding of the reciprocating mechanisms involved, let’s examine how the different types of reciprocating positive displacement pumps function.
Piston pump:在气缸内，将覆盖全直径的活塞向后拉，从而增加了腔体的体积。随着该腔体积的增加，流体通过入口吸收并填充了圆柱体。当活塞完全拉回后，流体是静态的，然后当活塞推回腔中时，它会产生差压力以克服出口阀，从而使流体离开。重复该过程。
Plunger Pumps: Plunger pumps operate similarly to piston pumps where a shaft moves back and forth in a cylinder, but the plunger component does not fill the diameter of the cylinder. Based on the design the seal is easier to maintain, as it is stationary at the end of the cylinder as the shaft moves, opposed to a piston pump that moves the seal with the reciprocating component.
Diaphragm Pumps:These pumps have multiple chambers or cavities where fluid is transferred through. They have a flexible membrane material that alternates the pressure and space between these chambers. The membrane expands to one side increasing the pressure, exiting the fluid through the outlet valve. At the same time, on the other side of the membrane, it is retracted increasing the volume on that side, pulling fluid through the inlet valve. The membrane design keeps these pumps completely airtight, removing the need for a traditional seal.
优点
Operating in repeatable cycles, a reciprocating positive displacement pump’s output can achieve high-efficiency rates around 90% and are preferred when precise metering is required. They are designed to handle low flow, high head applications, and high viscosity fluids. The variety of materials that the input and output ends can be made from make them suitable to handle abrasive and corrosive fluids. Most of these positive displacement pumps are self-priming. The compression motion for each output means the fluid output is not affected by pressure and is more consistent.
缺点
尽管可以准确测量每个压缩，但循环作用会产生更可预测的输出，但确实会产生其他并发症。重复的循环作用会产生脉动放电，每次来回运动的往复运动组件。这可能导致振动和噪音，最终会导致需要定期维护的组件的空气和损坏。为了应对这些效果，许多往复泵都使用多个圆柱体与活塞/柱塞同时操作但相反（交替的）周期动作以平衡压力。泵也可能具有某种阻尼结构，以平滑产生的振动。
Applications
Reciprocating Positive Displacement pumps offer the high pressure and accuracy needed for the chemical, refinery, pharmaceutical, and water treatment industries. Piston and plunger pumps are often used for the same applications in high-pressure washing, oil production, and paint spraying. Diaphragm pumps are seen more in water treatment, oils, and corrosive liquids such as sludge, acid, and chemical transfer. Depending on the extra cylinders to compensate with pulsation or adding greater pressures, reciprocating positive displacement pumps are classified as Simplex, Duplex, Triplex, or Quintuplex. Duplex is common in oil-line pumping, mine dewatering, chemical, and petroleum transfers. Triplex is found when low pulsation is a high priority. Quintruplex is common in cement, sand-filled fluids, crude oil, acids, and mud.
Anderson Process提供了各种不同的品牌和类型的往复式PD泵，这些泵可以解决客户在需要准确的流体转移效率或高压输出时面临的情况。如果您有任何疑问或疑虑，我们经验丰富的员工随时准备提供全力支持，以帮助您找到适当的申请解决方案。