1、先用眼睛目測一下閥門的表面是否光澤均勻，還要注意是否有裂痕、脫皮和明顯的斑點等等，質量過關的閥門表面應該沒有砂眼，且涂層的表面是細密光滑均勻的，如果出現了上述所說的一些缺陷，是會直接影響它的使用壽命。

1. First, visually inspect the surface of the valve to see if it has a uniform luster, and also pay attention to whether there are cracks, peeling, and obvious spots. The surface of the valve with good quality should not have sand holes, and the coating surface should be fine, smooth, and uniform. If any of the above-mentioned defects occur, it will directly affect its service life.

2、見過閥門的都知道，它的管螺紋與管道是直接相連接的，在選購時還要觀察管螺紋是否有明顯缺陷，還有管螺紋的有效長度，這將影響密封的可靠長度，這些都是需要用我們的雙眼仔細觀察的。

2. Anyone who has seen a valve knows that its pipe thread is directly connected to the pipeline. When purchasing, it is also necessary to observe whether there are obvious defects in the pipe thread and the effective length of the pipe thread, which will affect the reliable length of the seal. These are all things that require careful observation with our eyes.

3、閥門的材質有很多，不要貪圖小便宜，有些售價比較低的，會容易因腐蝕而斷裂，使用時間長了爛在管道中，在維修中會造成很大的困難。再者，選擇合適的閥門關重要，閥門品種規格很多，選擇不合適的會造成很大的影響。

3. There are many materials for valves, so don't be tempted by cheap prices. Some valves with lower prices may easily break due to corrosion, and if used for a long time, they will rot in the pipeline, causing great difficulties in maintenance. Furthermore, selecting the right valve is crucial as there are many types and specifications of valves, and choosing the wrong one can have a significant impact.