มาตรฐาน ASME B31.3 : การเปลี่ยนแปลงและผลกระทบต่อการออกแบบระบบท่อ Here is the significant technical changes of process piping code ASME B31.3 in 2004 edition and their impacts to piping system design. The changes are in following topics: 1. Weld joint strength reduction factors, W 2. Stress range factor, f 3. Alternate allowable stresses for occasional loads at elevated temperatures 4. Alternative rules for flexibility analysis 5. Temperature to be used for flexibility analysis 6. Ovalization limits for pipe bends 7. Repair as per API 570 or component replacement 8. Specfic design requirements for expansion joints 9. Pipe stress example problems 10. Allowable variations in elevated temperature service 11. Thermoplastics permitted with listed conditions 12. Other changes. ...