19
■
The air conditioning piping system should have sufficient conveying capacity. For exam ple, in the central air
conditioning system, the water system is used to ensure that the circulating water volume of each air conditioning
unit or fan coil air conditioner reaches the designed flow to ensure the normal operation of the unit;
■
Reasonable layout of pipelines: The layout of pipelines should be the same as possible. Although the initial
investment is slightly increased, it is easy to maintain the hydraulic stability of the loop. If an external system is
used, the pressure between the branches must be paid attention to in the design.Balance problem;
■
When determining the pipe diameter of the system, it should ensure that the design flow can be transmitted, and
the resistance loss and water flow noise are small to obtain economical and reasonable effects. As we all know,
the large diameter of the pipe is more investment, but the flow resistance is small, the power consumption of the
circulating water pump is small, and the freight is used low. Therefore, a pipe diameter that can minimize the sum
of investment and operating costs should be determined. At the same time, in the design to eliminate the problem
of large flow and small temperature difference, this is the economic principle of pipeline design;
■
In the design, strict hydraulic calculations must be carried out to ensure that the water balance requirements
are met between the various loops, so that the air conditioning water system has good hydraulic and thermal
conditions in actual operation;
■
The air conditioning piping system must meet the adjustment requirements for the central air 17 conditioning
part load operation;
■
Energy-saving technical measures should be adopted as much as possible in the design of air-conditioning
piping systems;
■
The pipe and fittings used in the piping system should meet the local requirements;
■
Pay attention to the maintenance and management of the piping system design, easy to operate and adjust.
Air conditioning piping system design
Determination of pipe diameter of air conditioning water system
The pipe diameter d is determined by the following formula:
We recommend that the water flow rate in the water system be selected according to the recommended values in
Table 1. The pipe diameter is determined by trial calculation, or the pipe diameter is determined according to the
flow according to Table 2.
d =
4m
w
3.14v
In the middle: m
w
------Water flowm
3
s
v--------Water flow ratem s
/
/
Pipe diameter(mm)
12
20
25
32
40
50
65
80
Closed water system
0.4-0.5
0.5-0.6
0.6-0.7
0.7-0.9
0.8-1.0
0.9-1.2
1.1-1.4
1.2-1.6
Open water system
0.3-0.4
0.4-0.5
0.5-0.6
0.6-0.8
0.7-0.9
0.9-1.0
0.9-1.2
1.1-1.4
Pipe diameter(mm)
100
125
150
200
250
300
350
400
Closed water system
1.3-1.8
1.5-2.0
1.6-2.2
1.8-2.5
1.8-2.6
1.9-2.9
1.6-2.5
1.8-2.6
Open water system
1.2-1.6
1.4-1.8
1.5-2.0
1.6-2.3
1.7-2.4
1.7-2.4
1.6-2.1
1.8-2.3
