Selection Principles of Strainers
According to the needs of manufacturing process and pipeline installation, as well as the overall performance of various types of strainers, selection principles and note points of strainers can be summarized as follows:
1. To ensure the tightness of the pipe system, you can select socket welded or butt welded strainers; and for easy replacement, threaded connection or flange connection strainers are favorable.
2. Body material of strainers should always be same with connected pipe material.
3. Working media with more solids content should select a strainer
with larger filter area.
4. Generally, permanent strainers are those strainers who have more than three times the filtration area of the cross-sectional area of the pipe. Temporary strainers have more than 2 times the effective filtration area of the cross-sectional area of the pipe.
5. Filter mesh number should be considered to meet the process needs, or play a protective role for pumps, compressors and other fluid transfer machinery.
6. Choose the type according to the actual piping requirements. Generally, SY1, ST3, SD1, SD2 and other similar types should be installed on the straight section; ST1, ST2 type is best installed in 90 °flow line variation section to save elbow; and SC1, SC2 type can be installed on both sections above.
7. In addition to SC1, SC2 type (don't need dedicated support) and DN200-300 SD2 type (has support leg itself), there is no supporting member for other strainers and piping designers need to considerate the supporting way.