Downloaded 976 times
More Related Content
Corrosion under insulation
- 1. Corrosion Under Insulation Loop steam drum Present by : Patiphon Suksawat
- 2.
- 3. Leader Patiphon Suksawat Consultant Wasan Cheeppensuk Atip Nualnet CUI team Komsan Bangkrut Nawa Bunsayang Narong Sakulprasitsiri
- 4. What is CUI(Corrosion Under Insulation) ? - CUI is a particularly severe form of localized corrosion that has been plaguing chemical process industries since the energy crisis of the s forced plant designers to include much more insulation in their designs - Intruding water is the key problem in CUI Special care must be taken during design not to promote corrosion by permitting water to enter a system either directly or indirectly by capillary action
- 5. What is CUI(Corrosion Under Insulation) ? External damage Carbon steels or Stainless low alloy steels steels Subject to stress Subject to thinning corrosion cracking
- 6. • CUI is the mainly problem in petrochemical plant. • Current Inspection Program is not consider corrosion under insulation problem. • Increase Reliability of Plant. Reference TPE
- 7. Conclusion and Futureaction Plan Inspection ( Visual and Ultrasonic Testing) Risk Evaluation and Identification List up EQ and Collection Data Make Inspection Guide Line (Check Sheet) Select Loop To Implement CUI Study CUI Theory From API 581, 570
- 8.
- 9. Insulated Piping Systems Susceptible to CUI 1. Carbon steel piping systems, including those insulated operating between (– C to C). 2. Austenitic stainless steel piping systems operating between ( C– C).
- 10. Common Locations onPiping Systems Susceptible to CUI Flange Tee Valve
- 11. Common Locations onPiping Systems Susceptible to CUI Ve nt Insulation has Support point
- 12. Guide Line forCUI inspection No Yes No Yes - 12 -
- 13. Check Sheet - 13 -
- 14. Loop steam drum TE-201 PM-500 A,B PE-302 TD-1203 TD-1201 TD-1210 TA-203A PE-502 PD-1205
- 15. List up Equipment No. Line No. No. Line No. 10BW-0201-4B-3P2-H3-17K 1S-0201-2B-P2 10BW-0202-4B-3P2-H3-17K 1S-0202-1.5B-P2 10BW-0203-2B-1P2-H3-13.5K 1S-0203-2B-P2 10BW-0205-3B-P2(1S1(V))-H2-5K 1S-0205-3B-P2 10BW-0208-6B-1P2-H3-13.5K 25SC-0001-6B-3P2-H3-28.5K 10BW-0209-6B-1P2-H3-13.5K 25SC-0001-6B-3S1-H3-28.5K 10S-0006-4B-1P2-H3-13.5K 25SC-0004-6B-3S1-H3-28.5K 10SC-0001-6B-1S1(V)-H3-13.5K 3BW-0201-3B-1P2-H2-13.5K 10SC-0002-4B-1P2-H3-13.5K 3BW-0202-3B-1P2-H2-13.5K 1BW-0201-6B-P2-H-9.5K 3BW-0203-1B-1S1(V)-H2-5K 1BW-0202-6B-P2-H-9.5K 3BW-0203-1B-P2-H2-5K 1BW-0203-1.5B-1S1(V)-H-5K 3BW-0204-3B-P2-H2-5K 1BW-0205-2B-P2-H-9.5K 3BW-0204-4B-PS(1S1(V))-H2-5K 1BW-0206-3B-P2-H-9.5K 3BW-0205-3B-P2-H2-5K 1BW-0210-6B-P2-H-5K 3S-0001-12B-P2-H2-5K 1BW-0211-8B-P2-H-5K 3S-0009-4B-P2-H2-5K 1BW-0212-8B-P2-H-5K 3SC-0008-8B-1S1(V)-H2-5K 1BW-2202-4B-P2-H-5K 3SC-0202-3B-P2(1S1(V))-H2-5K 1S-0001-4B-P2-H-5K 3SC-5502-4B-P2-H2-5K 1S-0005-6B-P2-H-5K LPW-0001-3B-1S1(J)-H-13.5K - 15 -
- 16. List up Equipment No. Line No. No. Line No. 10BW-0205-3B-P2(1S1(V))-H2-5K 25SC-0001-6B-3S1-H3-28.5K 25SC-0004-6B-3S1-H3-28.5K 10SC-0001-6B-1S1(V)-H3-13.5K 1BW-0201-6B-P2-H-9.5K 3BW-0203-1B-1S1(V)-H2-5K 1BW-0202-6B-P2-H-9.5K 1BW-0203-1.5B-1S1(V)-H-5K 1BW-0205-2B-P2-H-9.5K 3BW-0204-4B-PS(1S1(V))-H2-5K 1BW-0206-3B-P2-H-9.5K 1BW-0210-6B-P2-H-5K 1BW-0211-8B-P2-H-5K 1BW-0212-8B-P2-H-5K 3SC-0008-8B-1S1(V)-H2-5K 1BW-2202-4B-P2-H-5K 3SC-0202-3B-P2(1S1(V))-H2-5K 1S-0001-4B-P2-H-5K 1S-0005-6B-P2-H-5K LPW-0001-3B-1S1(J)-H-13.5K - 16 -
- 17.
- 18.
- 19.
- 20. Consequence of failurerating Consequence 1 2 3 4 5 class No / Slight Minor Local Major Extensive Economics Damage Damage Damage Damage Damage < 0.4 M 0.4 – 4 M 4 – 40 M 40 – 400 M > 400 M No / Slight Multiple Health & Safe Minor Injury Major Injury Single Injury Injury Injury No / Slight Minor Localized Major Massive Environment effect effect effect effect effect Select 3 Example - 20 -
- 21. Probability Score Tableof Carbon Steel Initial Operating Wall thickness Internal corrosion External coil / External Point Coating Insulation Type Temperature surface feature / erosion rate Steam tracing environment Status > 175 0C Full QA paint 0 Or Negligible Not present Inside Building protection < -5 0C Perlite Foamglass Rarely wetted Low High Integrity 1 150 – 175 0C Closed cell >7.1 mm (<10% of the ( < 0.1 mm/y) design Foam (right time) type) Normal QA Fiberglass 4 – 7.1 mm or -5 – 500C paint Cal Sil, surface location Intermittently Medium Medium Integrity 3 or protection Asbestos of penetrations wetted (~40% of (0.1-0.4 mm/y) design 120 – 150 0C field weld at Mineral Rock through the time) construction wool insulation < 4 mm or Permanently surface at wetted (e.g. Unpainted or location of High Low Integrity 5 50 – 120 0C condensation, Unknown reinforcement ( >0.4 mm/y) design cooling tower ring & other dripping water 5+5+1+1+1+0+1 = 14 water traps score Example
- 22. Probability Score Tableof Stainless Steel Operating Initial Coating External coil / External Points Insulation Type Temperature Status Steam tracing environment Constantly > 150 Low chloride 0C or Constantly Full QA paint 0 insulation material Not present Inside Building protection < 50 0C (<10 ppm Cl-) Rarely wetted High Integrity 2 (<10% of the design time) Permanently Normal QA paint protection field wetted (e.g. Medium Integrity 4 120 – 150 0C weld at condensation, design construction cooling tower dripping water Higher chloride Intermittently Unpainted or Low Integrity 7 50 – 120 0C insulation material wetted (~40% of Unknown design (>10 ppm Cl-) the time) score - 22 -
- 23. CUI Criticality ranking Example - 23 -
- 24. CUI Confidence rating CUI Confidence Questions Yes Interm NO Cladding and Insulation conditions -Cladding/Insulation fully maintained : Yes +1 0 -1 0 -1 + 0 = - 1 -Cladding/Insulation normal : Interm -Cladding/Insulation in poor condition : NO Multiple reliable inspections for CUI have been carried been carried out -Frequent inspection and selective delagly fallowed by +1 0 -1 appropriate remedial action : Yes -Inspection irregular / not standard : Interm - No proper inspections : No Monitoring CUI promoting condition - The pressure of all possible CUI promoting condition (see susceptibility categories) has been established and quantified : Yes - The operating temperature is monitored and constantly +1 0 -1 in identified rouge and coating condition is know / established : Interm - The operating temperature is not established or the coating condition is not know : No score Example - 24 -
- 25. Strategy Matrix forCarbon Steel Strategy 3 Example - 25 -
- 26. Strategy Matrix forStainless Steel - 26 -
- 27.
- 28.
- 29.
- 30. Strategy flowchart Strategy 3 Yes No Piping > 8 in 100 % NDE and delegging of all Delegging of susceptible area within 6 years susceptible within 6 years Yes No Significant CUI found Every Delag 100% Delag more selective area 6 years within 1 year Within 1 year Every 6 years Significant CUI found No Repair and Paint Yes 100 % delegging , repair and paint Adjust confidence within 1 year with +1
- 31. Risk Evaluation andIdentification
- 32. CUI Criticality ranking Medium High Medium Noinspection
- 33. Strategy Matrix Strategy Strategy No inspection
- 34.
- 35.
- 36.
- 37.
- 38.
- 39.
- 40.
- 41.
- 42. Strategy flowchart Strategy 3 Yes No Piping > 8 in 100 % NDE and delegging of all Delegging of susceptible area within 6 years susceptible within 6 years Yes No Significant CUI found Every Delag 100% Delag more selective area 6 years within 1 year Within 1 year Every 6 years Significant CUI found No Repair and Paint Yes 100 % delegging , repair and paint Adjust confidence within 1 year with +1
- 43.
- 44. Risk management Corrosion Think of module Friendship
- 45.
- 49. N/A = notavailable Internal Use Only – Do not distribute