Transcript
  • 1/27/2014 CR4 - Thread: Pipe Wall Thickness

    http://cr4.globalspec.com/thread/42250/Pipe-Wall-Thickness 1/3

    #1

    #2

    Sites: GlobalSpec.com | GlobalSpec Electronics | CR4 | Electronics360

    Previous in Forum: Material for Evaporator and Condenser Coil Next in Forum: Boiler Water Flow Rate

    viv1301Member

    Join Date: Mar 2008Location: IndiaPosts: 6

    Pipe Wall Thickness08/20/2009 12:48 PM

    Hi all,

    Is there a consideration of mill tolerance in pipe wall thickness calculation for a API 5L pipe designed as per ASME B31.3?

    Please suggest.

    Thanks in advance

    VIV

    Interested in this topic? By joining CR4 you can "subscribe" tothis discussion and receive notification when new comments are added.

    Join CR4, The Engineer's Place for News and Discussion!

    Comments rated to be "almost" Good Answers:Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!

    #2 "Re: Pipe Wall Thickness" by Abdel Halim Galala on 08/22/2009 4:48 AM (score 1)

    b v raoPower-User

    Join Date: Feb 2009Location: IndiaPosts: 156

    Re: Pipe Wall Thickness08/20/2009 11:44 PM

    Pipes come with standard thickness. It is for you to consider mill tolerance allowance in thk calculations. The tolerancesare specified in respective pipe standard. You can assume a safe tolerance of 12.5%

    Abdel HalimGalalaGuru

    Join Date: Feb 2007Location: Cairo, EgyptPosts: 1749Good Answers: 237

    Re: Pipe Wall Thickness08/22/2009 4:48 AM

    Refer to API 5L, Para 7.3 "Wall Thickness" and Table 9 "Tolerances for Wall Thicknesses".

    Quoted

    7.3 Wall Thickness

    Each length of pipe shall be measured for conformance to the specified wall thickness requirements. The wall thicknessat any location shall be within the tolerances specified in Table 9, except that the weld area shall not belimited by the plus tolerance. Wall thickness measurements shall be made with a mechanical caliper or with a properlycalibrated nondestructive inspection device of appropriate accuracy. In case of dispute, the measurement determinedby use of the mechanical caliper shall govern. The mechanical caliper shall be fitted with contact pins having circularcross sections of 1/4 in. (6.35 mm) diameter. The end of the pin contacting the inside surface of the pipe shall berounded to a maximum radius of 11/2 in. (38.10 mm) for pipe of size 65/8 or larger, and to a maximum radius of d/4 forpipe smaller than size 65/8, with a minimum radius of 1/8 in. (3.2 mm). The end of the pin contacting the outsidesurface of the pipe shall be either flat or rounded to a radius of not less than 11/2 in. (38.10 mm).

    Table 9 Tolerances for Wall Thicknesses

    . Tolerance (% of Specified Wall Thickness)

    Size Type of Pipe Grade B or Lower Grade X42 or Higher

    2 7/8 All + 20.0, -12.5 + 15.0, -12.5

    > 2 7/8 and < 20 All + 15.0, -12.5 + 15.0, -12.5

    20 Welded + 17.5, -12.5 + 19.5, -8.0

    20 Seamless + 15.0, -12.5 + 17.5, -10.0

    Unquoted

    As you see from Table 9, the min. tolerance for all type of pipe and its grades and NPS's is -12.5%, but the max.tolerance varies depends on the type of pipe and its grades and NPS's.

    Note. You can use and apply the tolerances at Table 9 even you make your design calculations as per ASME B31.3.

    __________________It is better to be defeated on principles, than to win on lies!

    The Engineer's Place for News and Discussion Login | Register

  • 1/27/2014 CR4 - Thread: Pipe Wall Thickness

    http://cr4.globalspec.com/thread/42250/Pipe-Wall-Thickness 2/3

    #3

    #4

    #5In reply to #4

    #6

    Copy to Clipboard

    No more "Almost" Good Answers.

    viv1301Member

    Join Date: Mar 2008Location: IndiaPosts: 6

    Re: Pipe Wall Thickness08/22/2009 10:48 PM

    Thanks guys for your reply and time.

    Abdel HalimGalalaGuru

    Join Date: Feb 2007Location: Cairo, EgyptPosts: 1749Good Answers: 237

    Re: Pipe Wall Thickness08/27/2009 11:29 AM

    The same your post #21 at Piping Class Materials and post #11 at Arabian Heavy Crude and Flow Rate .

    __________________It is better to be defeated on principles, than to win on lies!

    AnonymousPoster

    Re: Pipe Wall Thickness08/27/2009 1:35 PM

    uh ?

    viv1301Member

    Join Date: Mar 2008Location: IndiaPosts: 6

    Re: Pipe Wall Thickness01/31/2010 3:38 AM

    Hi Everybody,

    What would be the effect on Mill tolerance for an API SPEC 5L pipe due to provision of both Diameter and ThicknessTolerances? Does specifying Thickness tolerance alone in the Pipe Wall Thickness Calculation and mentioning the OD ofpipe to comply with ASME B 36.10 help?

    Please suggest if any, and please correct me in case my interpretation on this is wrong.

    Thanks in Advance,VIV

    Register to Reply 6 commentsBack to top

    Interested in this topic? By joining CR4 you can "subscribe" tothis discussion and receive notification when new comments are added.

    Join CR4, The Engineer's Place for News and Discussion!

    Comments rated to be "almost" Good Answers:Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!

    #2 "Re: Pipe Wall Thickness" by Abdel Halim Galala on 08/22/2009 4:48 AM (score 1)

    Users who posted comments:

    Abdel Halim Galala (2); Anonymous Poster (1); b v rao (1); viv1301 (2)

    Previous in Forum: Material for Evaporator and Condenser Coil Next in Forum: Boiler Water Flow Rate

    You might be interested in: Pipe Hangers and Pipe Supports, Pipe and Tube Cutters, Pipe Fittings

  • 1/27/2014 CR4 - Thread: Pipe Wall Thickness

    http://cr4.globalspec.com/thread/42250/Pipe-Wall-Thickness 3/3

    "You say I started out with practically nothing, but that isn't correct. We all start with all there is. It's how we use it that makes thingspossible." -- Henry Ford

    All times are displayed in US/Eastern (EST) (Register to change time zone)

    2014 IHS. GlobalSpec, the GlobalSpec logo, SpecSearch, the Engineering Web,

    the Engineering Search Engine, CR4 and Conference Room 4 are registered trademarks of IHS.All other company and product names may be trademarks of their respective owners. No portion

    of this site may be copied, retransmitted, reposted, duplicated or otherwise used without theexpress written permission of IHS GlobalSpec, 30 Tech Valley Dr. Suite 102, East Greenbush, NY, 12061


Top Related