（1） Classify by structural form.

1. Open lifeboat: It is a type of lifeboat without a fixed canopy device.

2. Partially enclosed lifeboat: It is a lifeboat with fixed rigid canopies of not less than 20% of the length at the bow and stern, and a foldable canopy in between. The foldable canopy can be supported by 1-2 people.

3. Fully enclosed lifeboat: It refers to a lifeboat with a fixed roof on the upper part of the boat, which has good insulation and water tightness.

n our daily lives, we often encounter mechanical failures, so mastering certain fault diagnosis methods is very important. Hydraulic stations are ubiquitous in our daily lives and play an important role. This product is a crucial component of hydraulic systems, capable of controlling the direction, pressure, and flow rate of oil flow. Generally, in order to reduce our usage failures, everyone needs to understand the knowledge of using hydraulic stations.

Gear Pumps

1. Repair of the working surface: If the wear on the working surface of the pump cover is relatively small, you can use the self grinding method to eliminate the wear marks. That is, place a small amount of valve sand on the path or thick glass plate, and then place the pump cover on top for grinding until the wear marks are removed and the working surface is flat. If the wear depth of the working surface of the pump cover exceeds 0.1 millimeters, it is necessary to repair it by fi