analysis of Poly pipe and RL pipe

Posted by: Gji

analysis of Poly pipe and RL pipe - 09/10/04 01:29 AM

Hi,

Can you let me know how to analyse the HDPE pipe size ranging from 300 to 1000 with the operating temperature of 50 deg C.

how to assume the outside temperature of rubberlined pipe with the fluid temp of 95 deg C . rubber lining thickness is 6 mm. How to assume the outside temperature of carbon steel pipe assuing the rubber's poor thermal conductivity.
Posted by: Manoj Sarkar

Re: analysis of Poly pipe and RL pipe - 09/10/04 02:42 AM

For stress analysis of HDPE pipe, you need the following information from vendor pertaining HDPE material properties :
Sh, r=Sa(0:1)/Sa(2:1), Eff (f2), Fac (k), Emodulus axial, E modulus hoop, Shear modulus, Poisson's ratio Axial/ hoop, Density & Expansion coefficient.

In C2 setup - FRP Properties field enter the relevant data. In spread sheet select material no.20 and design code as UKOOA. Enter material properties in the respective field. Then check stress in operating case only. Suitable support span to be maintained to keep sagging less than 1mm. The analysis can be carried out based on BS7159 or ANSI B31.3 with minor changes in method.

Regards
Posted by: Bruce Hebb

Re: analysis of Poly pipe and RL pipe - 09/10/04 04:57 AM

Gji,

Mr. Sarkar's recommendations are appropriate for an orthotropic and non-ductile material such as Fiberglass. HDPE is not orthotropic, nor is it non-ductile. HDPE is isotropic and ductile, so more traditional methods of analysis should be used. However, at 50°C, creep could be of considerable importance. I would strongly encourage you to discuss with your vendor, issues such as material properties at elevated temperatures, and appropriate methods of analysis.

Regards,
Bruce Hebb