From the perspective of the whole Lianggong valve mall, gate valve and stop valve are mainly selected as the primary blocking valve. In recent years, with the successful development of new products such as metal sealed double bias and three bias butterfly valves and metal sealed ball valves, the selection in petrochemical, electric power and metallurgy has gradually increased, replacing some gate valves and stop valves. Most oil and natural gas pipelines use ball valves and flat gate valves to facilitate pigging. Some of the gate valves and globe valves originally selected in urban water supply and heating systems have been gradually replaced by butterfly valves and soft seal gate valves. In the whole valve shopping mall, with the continuous development of science and technology, the following characteristics appear:

1、蝶閥和球閥因為研制成金屬密封構(gòu)造后，其溫度和壓力規(guī)模得到了擴展，將逐步替代一部分閘閥和截止閥。

1. Butterfly valve and ball valve will gradually replace some gate valves and globe valves because their temperature and pressure scale have been expanded after they are developed into metal sealing structure.

2、對夾式止回閥，安裝便利，體積小，也得到廣泛選用，將替代一部分升降式止回閥和旋啟式止回閥。

2. The wafer check valve has the advantages of convenient installation and small volume, and is also widely used. It will replace some lifting check valves and swing check valves.

3、大口徑止回閥方面，緩閉蝶形止回閥將替代大口徑旋啟式止回閥。

3. In terms of large-diameter check valve, the slow closing butterfly check valve will replace the large-diameter swing check valve.

4、蒸汽疏水閥方面，自在浮球式以其背壓高、漏汽量小和動作牢靠等特點將替代動作時噪聲大和漏汽量大的圓盤式蒸汽疏水閥。

4. In terms of steam trap, the free floating ball type will replace the disc steam trap with high noise and large steam leakage due to its high back pressure, small steam leakage and reliable action.

5、電動設(shè)備將選用傳感器和光電管構(gòu)造的智能型電動設(shè)備，用于閥門的智能化操控，滿意閥門程控、群控自動化系統(tǒng)的需求。

5. The intelligent electric equipment constructed by sensors and photocells will be selected for the electric equipment to be used for the intelligent control of the valve and meet the needs of the valve program control and group control automation system.