Fitness-for-Service (API 579), Fatigue and Remaining Life Assessment
Corrosion, metal loss, pitting, dents, bulges or cracks do not always mean replacement. A fitness-for-service (FFS) assessment shows whether equipment can stay in service, at what pressure and for how long.
SLETEC performs API 579-1/ASME FFS-1 Level 1, 2 and 3 assessments, remaining life calculations to API 510, 570 and 653, fatigue analysis to ASME VIII Div. 2 and BS 7608, and fracture mechanics using FEA.
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What we calculate (Tank, Vessel and Heat Exchanger Calculations)
API 650 shell, bottom and roof design
tank thickness calculation (API 650, AMETank / Excel)
Wind girder, overturning and seismic design
tank wind and earthquake check (API 650 Annex E)
API 653 minimum thickness, remaining life and repair
tank repair calculation (API 653)
Tank venting calculation
tank vent size (API 2000)
Tank settlement evaluation
tank settlement check (API 653 Annex B)
ASME VIII Div. 1 shell, head and nozzle design
vessel thickness calculation (PV Elite / COMPRESS)
MAWP, MDMT and hydrotest pressure
vessel max pressure (ASME VIII)
Nozzle reinforcement and pad design
nozzle reinforcement (ASME VIII UG-37)
Zick saddle analysis, skirt and leg supports
saddle / skirt / leg check (ASME VIII, Zick method)
Wind and seismic loads on vessels and columns
vessel wind and seismic (ASCE 7, SBC 301)
Mechanical design to TEMA and ASME VIII
heat exchanger calculation (TEMA, PV Elite)
Tubesheet and expansion joint design
tubesheet calculation (ASME VIII UHX, TEMA)
Custom flange design
flange design (ASME VIII App. 2)
Remaining life and inspection interval
corrosion / remaining life (API 510, API 570, API 653)
FFS Level 1 / 2 / 3
fitness for service (API 579-1/ASME FFS-1)
Send us your drawings and data on WhatsApp (+966 55 545 8298) or email (enquiry@sletec.com) for a fixed-price quote, usually within 24 hours.
Frequently Asked Questions
What is fitness-for-service?
It is an engineering check to decide if damaged equipment is safe to keep running, needs repair, or must be replaced.
What data do you need?
Design drawings, inspection thickness data, photos of the damage and operating conditions.
Can you calculate remaining life?
Yes. We calculate remaining life and next inspection date from corrosion rates.
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