×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Coefficient of Thermal Expansion in Road/Rail Crossing Calculations

Coefficient of Thermal Expansion in Road/Rail Crossing Calculations

Coefficient of Thermal Expansion in Road/Rail Crossing Calculations

(OP)
API 1102 does not specify a value for coefficient of thermal expansion. It specifies a typical range of 1.6x10-5 to 1.9x10-5 (refer to Table A-2).

Clause 832.2 of ASME B31.8 states that “The thermal expansion and contraction of the more common carbon and low alloy steels may be calculated using 6.5 x 10−6 in./in./°F (1.17 x 10−5cm/cm/°C) as the coefficient of thermal expansion”. Also Clause 402.2.1 of ASME B31.4 states that “The linear coefficient of thermal expansion for carbon and low alloy high tensile steel may be taken as 6.5 x 10-6 in./in./°F for temperatures up to 250°F (11.7 x 10-6 mm/mm/°C for temperatures up to 120°C).

Both ASME B31.8 and ASME B31.4 recommend to use 11.7 x 10-6 mm/mm/°C as the coefficient of thermal expansion, but this is outside the range that is specified in API 1102.

What value for coefficient of thermal expansion should be used in road/railroad crossing calculation?

RE: Coefficient of Thermal Expansion in Road/Rail Crossing Calculations

API is a recommended practice, so even it's use is not exactly mandatory. In the general sense, whenever you have a "real" value, you should use it (with a good dose of your engineering judgement). In this case use 0.0000065 in/in-F.

"People will work for you with blood and sweat and tears if they work for what they believe in......" - Simon Sinek

RE: Coefficient of Thermal Expansion in Road/Rail Crossing Calculations

(OP)
Thanks BigInch. That was very helpful.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources