236 



SUBBIAEINE CABLE LAYES'G AND KEPAIEING. 



The volume in cubic feet per naut of any cable of diameter 

 inches is : — 



d V r. 



(b) 



7854 X 6,087 = 33- 2 f?2, 



and taking, say, Type D, the overall diameter of which is as 

 nearly as possible 0*9 inch, the volume per naut of this cable 

 would be 



33-2 X (•9)2 = 26-8 cubic ft. 



Roughly, therefore, the length of Type D that could be coiled 

 in this tank, per foot height, would be 



679 

 26-8 



= 25*3 nauts. 



This calculation is only rough, as it makes no allowance for the 

 waste space in coiling. It is obviously impossible, owing to the 

 circular section of the cable, to entirely fill up the space avail- 

 able ; and cable actually takes up more room than its calculated 

 volume. The amount of waste space varies according to the 

 size of the cable, and is greater for a large than for a small cable. 

 It is found that an allowance has to be made of from 10 per 

 cent, in small cables to 50 per cent, in large types to cover 

 waste space. After cable has been in tank some time it settles 

 down and the waste space is diminished, the decrease amount- 

 ing sometimes to 5 per cent. 



The following are the approximate overall diameters out- 

 side the yarn serving of different sizes of cable and the approxi- 

 mate percentages in each case to be allowed for waste space in 

 coiling : — 



Volume 

 of Cable 

 per naut. 



Type. 



Approx. 

 overall 

 diam. 



S E 



A 



El 



E 



H. I. 



iBi 



L.I. 



B 



Di 

 D 



2 35" 



1-76" 



1-57" 



1-5" 



1-32" 



1-25" 



1-1" 



1-05" 



l-OO' 



0-90" 



185-0 eft 

 102-8 „ 

 81-6 „ 

 75-0 „ 

 58-0 „ 

 51-9 „ 

 40-0 „ 

 36-6 „ 

 33-2 „ 

 26-8 „ 



Approximate 



percentage 



mci-ease for 



waste space. 



50% 

 45% 

 45% 

 40% 

 40% 

 30% 

 25% 

 25% 

 20% 

 •20% 



Approximate 



space per 

 naut in coiling. 



277 eft. 



150 „ 



119 „ 



105 „ 



81 „ 



68 „ 



50 „ 



46 „ 



40 „ 



32 „ 



