Need review for pipe wall thickness calculation sheet for pipes under internal pressure 9

[Asisraja D]

Hi professionals

i am a project engineer and i did some calculations part for calculating wall thickness for pipes under internal pressure as per ASME B31.3.
i have attached the sheet here.

This is just my work to submit to all of you for a review on the steps involved here and the Units i used here whether right or wrong ?
if anyone cross check the work please you can download and try this at free time. Thank you for all of your support to keep curious of engineering as part of my life.​

"Strive for perfection in everything you do. Take the best that exists and make it better. When it does not exist, design it." - Sir Henry Royce

 

[Asisraja D]

fel3
Sir i haven't heard about the software used for this kind of calculation, anyhow thanks for introducing them for me.


"Strive for perfection in everything you do. Take the best that exists and make it better. When it does not exist, design it." - Sir Henry Royce

 

[GD2]

OP,
You have gone wrong in two places:
1. 4.78 mm wall thk looks to be a non-standard pipe schedule - means you can't buy in the market.
2. t[sub]m[/sub]value must be equal or greater than t[sub]c[/sub].

correct these two and you should be fine.
GDD
Canada

 

[Asisraja D]

GD2
Thank you sir for correcting the errors in my sheet.

"Strive for perfection in everything you do. Take the best that exists and make it better. When it does not exist, design it." - Sir Henry Royce

 

[GD2]

OP,
You must go for either 30 Sch or 40 Sch pipe, depending on market availability.

GDD
Canada

 

[ShabsRBI]

Hi Asisraja,

Selection of piping thickness is not taken independently and in done in conjunction with the Flange ratings. Most of the organizations have the Piping classes, where depending upon the Pressure and temperature piping Schedule is decided. For your given conditions of Design Pressure of 1496 Kpa and Design Temperature of 200 Deg C, the flange and Flange fittings in the line will be #300 as with #150 flange and flange fittings you can maximum go at a Pressure of 1380 Kpa ( as per B16.5 Pressure- Temp ratings for Group 1.1 Material SA-105 ).

With Class #300 the allowed Pressure at 200 Deg C is 4380 Kpa, which is well above the design pressure of 1496 Kpa.

With flange rating of #300 the specified thickness is DN250 Standard Schedule with a thickness of 9.27mm

 

[ShabsRBI]

Hi Asisraja,

Normally the line thickness is not considered independently but in conjunction with Flange ratings. Most of the organizations have the line classes based on pressure and temperature ratings and then line classes are specified. For your case at design temperature of 200 Deg C and Design Pressure of 1474 Kpa, flange rating of #150 is not good because as per ASME B16.5 and material group 1.1 (Flange SA-105) the maximum Pressure at 200 Deg C is only 1380 Kpa. The next flange rating is #300 which is good for the given design temperature and design pressure. For flange rating of #300 the required schedule is normally selected as Standard Weight ( Sch-40).

For DN250 Sch-40 SA-106 Gr-B nominal thickness is 9.27mm.

 

[Asisraja D]

Hi ShabsRBI​

 

[Asisraja D]

@HI ShabsRBI​

As you mentioned

With Class #300 the allowed Pressure at 200 Deg C is 4380 Kpa, which is well above the design pressure of 1496 Kpa.

YEAH. I agree to go with #300 P-T rating.

Thanks for reviewing and correcting my document.