Hand wheel,lever and spanner driving and safety valve,pressure reducing valve,traps overleap this symbol.

1、手轮、手柄和扳手传动以及安全阀、减压阀、疏水阀省略本。

What's the code for Tianjin?

天津的多少?

The content of basic standard has: Method of code name of substantival term, symbol, mark, standard weaves the method.

基础准的内有：名词术语、符、方法、准编排方法等。