泵聯軸器 - 比較

What is a pump coupling?

泵耦合是用於將旋轉泵軸連接到電動機的驅動軸的元件;使電機能夠有效地向泵傳輸電力。

當泵接近耦合時，當電動機直接安裝到單個軸上時，不需要單獨的耦合。雖然近距離耦合泵受益於緊湊，成本效益的設計，但對於重型，高功率，連續使用，隨著普通軸承的壓力，電動機的尺寸通常有限，它們不太優選。

對於較重的職業應用，長耦合泵更適合。當泵和電動機安裝在其自身的軸上，通過聯接隔開，單獨的軸承共用操作應變，因此延伸了機械部件的壽命。

錯位問題

如果它們保持完全對齊並且操作期間沒有振動，則兩個軸的聯接器是簡單的。然而，實際上，這不是一種情況，並且任何未對準都可能導致軸承，機械密封件甚至耦合本身的過早磨損和失效。

未對準是當一個或兩個軸被迫從其所需位置時，其中有三種主要類型：

• Axial– Where the shafts are parallel but either too close or too far apart

• Radial– When one shaft is positioned higher than the other.

• 棱角– Where the two shafts are positioned at different angles to one another.

錯位問題是選擇耦合時需要考慮的因素之一，因為不同的類型應對不同的類型。那麼，什麼是不同類型的泵耦合，以及它們應該什麼時候？

Rigid couplings

As their name suggests, rigid couplings connect the pump and motor shafts together very firmly, which allows them to transmit more power to the pump than flexible couplings of a comparable size. They also benefit from a simpler, more cost-effective design. However, rigid couplings don’t have the ability to handle any shaft misalignment without high stress on the bearings and seals as are unable to absorb any vibrations from the pump running, or thermal expansion. They are usually used for applications where misalignment is not a concern, for example where the shafts have been precisely positioned in perfect lateral and angular alignment at installation.

Flexible couplings

Unlike rigid couplings, flexible couplings can accommodate some movement e.g. vibrations and thermal expansion without damage. This makes them ideal for applications where there is a degree of unavoidable misalignment between the drive and pump shafts. As they can absorb vibrations well, they can also be used to reduce excessive operating noise. With these benefits come a more complex, expensive design. However, as flexible couplings protect the shaft and bearings from damage and premature wear, there are maintenance savings to be had in the long run.

磁性聯軸器

磁耦合與剛性和柔性的而不是機械軸不同，電動機通過提供各種益處的磁鐵連接到泵。首先，有磁耦合泵there is a small air gap between the magnet and the motor and pump. As there is no physical contact, misalignment and thermal expansion is not a problem. The absence of a mechanical seal also eliminates the chance of leakages, making a magnetic drive pump ideal for handling aggressive or hazardous fluids.

However, magnetic couplings are only suited to clean liquids as the presence of any particles can be problematic as they stick to the magnet. They are also sensitive to extreme operating conditions; if excessive torque exceeds the capabilities of a magnetic coupling, the magnetics may decouple, and the pump shaft will slip causing stoppages. Therefore, when selecting a magnetic coupling, you need to be sure that is aligned with the power of the system.

概括

Below is a quick comparison of the performance of the three different types of coupling.

	Rigid	Flexible	磁的
類型	Mechanical	Mechanical	Non-Mechanical
扭矩 Transmission	Higher due to firm connection	Lower than a comparable rigid coupling	Can decouple under extremely high torque
Misalignment	不適合安裝 where misalignment is present	Can accommodate a certain degree of misalignment 在係統中	Absence of physical contact means it isn’t a problem
Vibration / Thermal Expansion	Unable to absorb	Able to absorb	Absence of physical contact means it isn’t a problem
成本	Lower	Higher	Higher