OTHER METALLIC PIPES 



Other than aluminum, there are no nonferrous pipes being made in 

 sufficient size and quantity for the heavy-lift operation. In fact, no aluminum 

 pipe is made which will satisfy all the requirements for the project in question. 

 Aluminum pipe currently manufactured is not large enough nor strong enough 

 to safely support its own weight and a 600-ton load at 6,000 feet. Table B-5 

 presents the specifications for the larger aluminum drill pipes currently 

 available. 



Table B-5. Specifications for Aluminum Pipe 



OD 



Wall 



Typical Breaking 



Weight With Tool 



Thickness 



Load 



Joints in Air 



(in.) 



(in.) 



(lb) 



(lb/ft) 



3-1/2 



0.512 



380,000 



7.87 



4 



0.460 



399,000 



9.68 



4-1/2 



0.500 



475,000 



10.75 



5 



0.525 



562,000 



13.75 



5-1/2 



0.500 



601,000 



14.45 



ADDITIONAL DESIGN CONSIDERATIONS 



Bending Stresses 



Currents acting normal to the pipe string can induce bending stresses 

 at the support point. The worst possible case is that in which the pipe is 

 assumed to have one fixed end. While this is not entirely possible for the 

 drill string, the assumption will give conservative answers for the design 

 analysis. The maximum moment, M^^gj^, due to bending is given by"^'' 



max \/ p 



Ctanh 



sech 



117 



