17 major avoidance principles in pipeline design and construction

1. Small tube makes big tube: The small tube is easy to bend and the cost is low.

2. Branch pipes to main pipes: branch pipes are generally smaller in diameter. See Article 1 for the reasons for avoidance. In addition, the scope and importance of branch pipes is not as important as that of main pipes.

3. Pressure tube to non-pressure tube (pressure flow tube to gravity flow tube): The pressureless tube (or gravity flow tube) changes the slope and flow direction, which has a greater impact on the flow.

4. Water supply pipe and drain pipe: In addition to the above-mentioned reason 3, the diameter of the drain pipe is usually large and there are many impurities in the water.

5. Normal temperature pipes should be high (low) temperature pipes (cold water pipes should be hot water pipes, non-insulated pipes should be insulated pipes): Exhaust should be considered when the temperature is higher than normal temperature; condensation prevention and insulation should be considered when the temperature is lower than normal temperature.

6. Low-pressure pipes let high-pressure pipes: high-pressure pipes are expensive and require high strength.

7. The gas pipe makes the water pipe: the power consumption of water flow is large.

8. Metal tube makes non-metal tube: Metal tube is easy to bend, cut and connect.

9. General ducts let ventilation ducts: The ventilation ducts are bulky and difficult to bend.

10. Small valve parts make more valve parts: consider factors such as installation, operation and maintenance.

11. Simple construction and avoid difficult construction.

12. Small engineering volume makes engineering volume large.

13. The pipeline with low technical requirements allows the pipeline with high technical requirements.

14. The convenience of less maintenance makes the frequent and inconvenient maintenance.

15. Non-main pipelines avoid main pipelines.

16. Temporary pipelines avoid permanent pipelines.

17. Newly built pipelines should avoid the already completed pipelines.