Volume 17, Issue 7 (9-2017)                   Modares Mechanical Engineering 2017, 17(7): 405-412 | Back to browse issues page

‎ 20.1001.1.10275940.1396.17.7.24.6

XML Persian Abstract Print

Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:
Nodeh Farahani M H, Sadeghi M H, Rasti A. Stress Analysis and Design Improvements of Rotating Drilling Pipe Tool Joints by Fatigue approach. Modares Mechanical Engineering 2017; 17 (7) :405-412
URL: http://mme.modares.ac.ir/article-15-2896-en.html
Stress Analysis and Design Improvements of Rotating Drilling Pipe Tool Joints by Fatigue approach
Mohammad Hossein Nodeh Farahani , Mohammad Hossein Sadeghi * , Amir Rasti
Abstract:   (3841 Views)
Nowadays, Ease of accessibility to natural oil and gas wells has fallen significantly due to continues drilling operations. Therefore, oil fields came after deep drilling and horizontal and directional drilling methods. However, due to more complex conditions in these wells, rods fails mostly. This failure occurs in rod joints as the weakest link. In this research, API NC46 standard tool joint has been investigated considering real oil well condition. The goal is to find the weakest points in the drilling rod and present an economical and practical solution to increase the life time. Results show that the maximum stress occurs in the first engaged thread of pin and last engaged thread of box which makes these areas more vulnerable. In the following, using optimization of joint main parameters including threads geometry, make-up torque and shoulder sealing design, a new plan will represent that have higher fatigue life than the similar API standard tool joint. Maximum stress concentration factor of improved tool joints relatively decrease from 3.47 to 2.86 compared to standard joint. In addition Experimental tests show that the average fatigue life of improved joint is 2.3 times more than the standard tool joint.
Keywords: Down-hole drilling, API tool joints, Fatigue Life
Full-Text [PDF 1384 kb]   (6566 Downloads)    
Article Type: Research Article | Subject: Stress Analysis
Received: 2017/04/5 | Accepted: 2017/06/11 | Published: 2017/08/4
Add your comments about this article : Your username or Email:
CAPTCHA
Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.