49 



Cement Pipe Data. 



Cost of making pipe. 



The table of cost given below is obtained from the above data and for 

 the following prices of labor and material: 



Portland cement, $3.50 delivered on the ground. 



Gravel, $1.00 a cubic yard. 



Labor: Tampers $3.00 a day; mixers and sprinklers, $2.50 a day. 



The figures given include all materials and labor and an allowance of 

 about 10 per cent, for interest and depreciation on plant, administration 

 and supervision, and should not be exceeded with efficient workers. 



Cost of Making Cement Pipes (in cents), per Lineal Foot. 



2. Construction and Laying of Pipe Line. 

 Excavation of trench. 



The pipe should be laid sufficiently deep below the surface to have an 

 earth covering of at least 12 inches and preferably 18 inches or even more. 

 The bottom of the trench should be graded on an even grade to avo:d short 

 siphons which may produce air chambers in the pipe. The width of the 

 trench should be larger than the outside diameter of the pipe by about 12 

 inches to allow the pipe layers sufficient space to work in. The trench 

 width and depth with the cost of excavation are given in the table below, 

 based on an 18 inch depth of earth covering. The cost of excavation and 

 backfilling is assumed at 20 cents a cubic yard. 



