.s/A' WILLIAM SIEMENS, E.K.S. 389 



o.\ THE CONSTRUCTION OF VESSELS TO RESIST 

 HIGH INTERNAL PRESSURE. 



BY DR. C. WILLIAM SIKMKNS,* D.C.L., F.R.S., 

 Past-President Inst. M.E. 



I\ constructing vessels intended to withstand a great internal 

 pressure, considerable practical difficulty has hitherto been 

 encountered. If boiler plate is used in their construction, the 

 seams of rivets are sources of weakness, and of uncertainty as to 

 resisting power, increasing with the thickness of the plate required 

 to withstand the intended strain. In consequence of these 

 practical difficulties, it has generally been thought advisable to 

 limit the diameter of cylindrical vessels intended to bear great 

 strain, and to resort to a multitubular construction. But here 

 again the difficulty of many joints is encountered ; and the vessels 

 constructed upon this principle necessarily occupy much more 

 room than a plain cylindrical vessel would do. When cast iron is 

 resorted to in the construction of such vessels, as in the case of 

 hydraulic presses and accumulators, the thickness required is so 

 great as to render the vessels extremely ponderous and costly ; 

 and it sometimes happens that the fluid under pressure finds its 

 way through the pores of the metal. At the present time the 

 occasions for the use of high-pressure vessels increase daily 

 with the application of compressed air as a motive agent, with the 

 application of hydraulic transmission, and with the introduction 

 of high-pressure steam for marine purposes, where the large 

 diameters of the boiler shells required necessitate the construction 

 of cylindrical vessels of great strength. 



The writer's attention was specially directed to this subject last 

 year by Colonel Beaumont, who asked him to advise regarding the 

 construction of a vessel of not less than 100 cubic feet capacity, 

 and capable of resisting an internal pressure of at least 1000 Ib. per 

 square inch. The dead weight of this vessel was not to exceed 

 '2\ tons, as it was intended to act as a reservoir of highly com- 



* Excerpt Minutes of Proceedings of the Institution of Mechanical Engineers, 

 1873, pp. 271-275, and pp. 286-290. 



