PSI - Issue 60

Thondamon V et al. / Procedia Structural Integrity 60 (2024) 484–493 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Healthy elbows with internal pressure M 0 M 0 (P=0) =1+αp+βp 2 +γp 3 ; p= P 0 σ y r t ; β=−0.85 ; γ=0.31 α = 0.35 ; β = −0.88 ; γ=0.08 α = −0.18 + 0.07 (Rt) β = 0.0005 (Rt ) 3 − 0.0075 (Rt) 2 + 0.0375 (Rt ) − 0.05 γ = −0.011 (Rt ) 2 + 0.110 (Rt ) − 0.880 Elbows with circumferential through-wall crack without internal pressure M X =X M 0 (P=0) α=−0.05 Weakening factor

R⁄t=5 R⁄t =10

Opening Moment

5≤R⁄t ≤10

Closing Moment

X = exp [− (θ⁄π) 2 0.1682 ] X= min[1.0−2.113 π θ +1.44]

Opening Moment Closing Moment

100 150 200 250 300 350 400

PRELHO-8 ELHO-8

Load (kN)

0 50

0

50

100

150

200

250

300

350

Displacement (mm)

Fig. 4. Load-displacement of healthy elbow with and without internal pressure.

100 120 140

PRELTWCIN 8-1 PRELTWCIN 8-3 HPRELTWCIN 8-1

0 20 40 60 80

Load (kN)

0

50

100

150

200

250

Displacement (mm)

Fig. 5. Load-displacement of elbows with through-wall crack with internal pressure.