These pumps are the longest and the simplest. They employ two parallel gears mounted on the shaft and can have single or double rows of teeth. The simplest version has a straight cut "straight tooth" gear in the form of an involute, but also offers "herringbone" and "spiral" teeth. The latter design is quieter and more efficient than a simple straight tooth, but it is also more difficult to manufacture.

All gear pumps rely on fine clearance, especially when dealing with thin fluids, to prevent internal leaks around the gear also known as "slippage." Therefore, gear pumps are less efficient when dealing with thin fluids, especially when the pressure difference is very high. The advantages of positive gear pumps are that they are well balanced and can operate at high speeds, often making them a better choice for thin fluids.

Gear pumps are capable of producing high pressure, so if the valve behind the gear pump is blocked or closed, it can cause problems. Internal decompression can prevent potentially dangerous situations. This will protect the gear pump from damage and prevent damage to the system downstream of the pump.

The above content is what is the external gear pump, and whether the gear pump needs an internal relief valve. In addition, Shenzhen Oudejie Technology specializes in the sale of new imported gear pumps, and promises to sell products are new imported, while providing our customers with quotation, selection, product information and other services.