水管管径d由下式确定：d=式中mw------------水流量,m³v------------水流速,m我们建议，水系统中管内水流速按表一中的推荐值选用，经试算来确定其管径，或按表二根据流量确定管径。表一、管内水流速推荐值（m）管径㎜1520253240506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
d=式中mw------------水流量,m³v------------水流速,m我们建议，水系统中管内水流速按表一中的推荐值选用，经试算来确定其管径，或按表二根据流量确定管径。表一、管内水流速推荐值（m）管径㎜1520253240506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
式中mw------------水流量,m³v------------水流速,m我们建议，水系统中管内水流速按表一中的推荐值选用，经试算来确定其管径，或按表二根据流量确定管径。表一、管内水流速推荐值（m）管径㎜1520253240506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
v------------水流速,m我们建议，水系统中管内水流速按表一中的推荐值选用，经试算来确定其管径，或按表二根据流量确定管径。表一、管内水流速推荐值（m）管径㎜1520253240506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
我们建议，水系统中管内水流速按表一中的推荐值选用，经试算来确定其管径，或按表二根据流量确定管径。表一、管内水流速推荐值（m）管径㎜1520253240506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
表一、管内水流速推荐值（m）管径㎜1520253240506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
1520253240506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
20253240506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
253240506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
3240506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
40506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
506580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
6580闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
80闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
闭式系统0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
0.4~0.50.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
0.5~0.60.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
0.6~0.70.7~0.90.8~1.00.9~1.21.1~1.4
0.7~0.90.8~1.00.9~1.21.1~1.4
0.8~1.00.9~1.21.1~1.4
0.9~1.21.1~1.4
1.1~1.4