THERMOWELL STRENGTH CALCULATIONASME PTC 19.3 TW-2010[ PROCESS CONDITION ](1)(2)
Tag No.
(3)
Operating temperature(4)
Operating pressure(5)
Fluid density(6)
Fluid viscosity(7)
Flow rate(8)
Pipe.inner dia.
(9)
Fluid velocity

Sep. 3, 2015

SHELL
T°C
PbarG
γkg/m3
μcP
Q
DDmm
Vm/s

3.80
Type of Thermowell :
316SS
30.0
14.0
6.5
300.0
150.0
150.0

[ CALCULATION RESULT ]Judgement :[1]
Frequency Limit Calc.
HzStrouhal frequency
fsc
Hz
Natural frequency
fnPass
54.7
281.7

[2]
[3]
[4]

fs / fnc = 0.194 < 0.4(16)(17)[ REMARKS ]Fatigue endurance limit
Allowable stressSensor average density
Young’s modulusDensity of thermowell

SfSγsEγm2[ Calculation Method : ASME PTC 19.3 TW-2010 ][1] Frequency Limit Calc.
V3
fs = St
Strouhal frequency
D 10
Natural Frequency

Fillet radiusbTip thickness t

Notes 1:Sign
Calculation report
LDWG & Specification sheet U
Notes 2: Since calculation of a 2 phaseflow assumes that it is a single phaseflow in mean density, please consider
that the result is an object for reference.

mmmm3.05.0

N/mm2 193.50<Allowable stress 1.5S

<Allowable stress FT FE Sf

N/mm2Pass
External pressure rating for tip shank Pc MPa
External pressure rating for the tip
Pt MPa

N/mm
93.8
129.0
N/mm2kg/m3
2 700
2N/mm 195 168
kg/m3
7 980

fnc=Hc fn

B3Reynolds No. Re
8 554 ≤ 10^5Scruton No. NSc
0.038 ≤ 2.5
Inline resonance velocity VIR
10.2 m/s
Stress at VIR Somax= 1369.1 > FT FE Sf = 94.0 N/mm2Upper frequency ratio limit

Pass
Steady-State Stress Calc. Judgement :2Stress using the Von Mises criteria N/mm
1.86Judgement :Pass
Dynamic Stress Calc.
Combind drag and lift stresses Somax N/mm2
1.98
Judgement :Pressure Stress Calc.
Operating pressure P MPa
0.10 <
Operating pressure P MPa
0.10 <REC.NO.

20
1.00
820.000
5.1000[ THERMOWELL SPECIFICATION ](10) MaterialA(11) Root out.dia.
mmBmm(12) Tip out.dia.
dmm(13) BoreLmm(14) Insertion lengthmm(15) Actual insertion length LA

Frequency ratio

AE 1TESTStrouhal No.
Damping factor
Stress concentration factor
Drag coefficient
Oscillating-drag coefficient
Oscillating-lift coefficient
Magnification factor (VIR)

65.17
587.16NSζKtCDCdClF'Mmax

λ2
fa = 2π L22

fn=Hf Haf Has fa

93.96

0.20
0.0005
1.4
1.40
0.10
1.00
1000.0E I 10 12m

VBγ
Re = μ1Somax = Kt (Sd2+SL2)1/2
Cyclic stress at the VIR
Pd = γ CdVIR2・10-6 N/mm2
Sd = GSP F'Mmax Pd2( SL=0 )
Bfnc
16L2
G
={3
[1-(L0 /L)2]+2(B/A-1)[1-(L0 /L)3]}
Inline resonance velocity
VIR =m/s
SP3πA2[1-(d/A)4]2NS
L0 = L - LA
[2] Steady-State Stress Calc. at the V
1(Smax- Sr)2+(Smax- St)2+(St - Sr)2
PD = γ CDV 2・10-6≤ 1.5S
Sd = GSP PD
Von Mises criteria
2212-622 1/2
2[3] Dynamic Stress Calc. at the VP=γCV・10N/mm2
Somax = Kt (Sd +SL ) N/mm SL = GSP FM Plll
2
Scruton No.

NSc = π2ζ (γm/γ)[1-(d/B)2](Same equation of cyclic stress)

Reynolds No.

FM =1.0F'M =[4] Pressure Stress Calc. (Max. Pressure)
2.167
External pressure rating for tip shank Pc = 0.66S- 0.0833
2B/(B - d)S
External pressure rating for the tip
Pt =( t )2 MPa
0.13 d[1.2] MPa

OKAZAKI MANUFACTURING COMPANY

Notes 3: "Pass *1" means that We Recommend to Use.
Freq. ratio "fs/fn" is higher than 0.4 and lower than 0.6.
This ratio is not recommened to use in ASME.
Notes 4: "Pass *2." means that we do not recommend touse. Fluid density>300kg/m3 and Freq. ratio fs/fn>0.2.
This ratio is able to use in ASME.
Program Version 4.3P June 17, 2015
FileMaker Pro Ver.13