TESTING STONEWARE PIPES USED IN RETICULATION SEWERS. LXI. 



Hameter. 



Thickness. 



Weight. 



Weight after 



Cross breaking- 



Inches. 



Inches. 



Dry. 



24 hours in water. 



18-inch centres. 



15 



n 



1441 



uq 



3,900 



12 



i 



97 



99J 



3,900 



9 



i 



7H 



781 



3,900 



6 



i 



37J 



38| 



4,480 



4 



* 



26 



271 



5,000 



Taking the average increase in weight, the result is 3-22 per 

 cent. With respect to internal pressure, the vast majority of 

 pipes tested stood 250 lbs per square inch before bursting, when 

 tested to destruction. 



The specified tests are as follows in Melbourne : — 

 Shape. — Each pipe will be tested by passing into it a wooden 

 dummy, truly cylindrical, or an anulus for the bends, but with a- 

 diameter f-inch less than the specified diameter of each particular 

 size of pipe ; and also by passing over the outside of the pipe & 

 ring of an internal diameter J-inch larger than the external 

 diameter of each size of pipe. Any pipe which these gauges do 

 not fit satisfactorily, will be at once rejected. The pipes will also 

 be examined for uniformity and suitability of burning and glaze. 



Internal pressure. — Pipes which have passed as above will then 

 be subjected to hydraulic pressure equal to a column of water 

 30 feet high, and while under this pressure the pipe will be 

 repeatedly struck with a wooden mallet. Any pipe showing 

 signs of sweating or leakage, either in the body or socket, will be 

 at once rejected. 



Permeability and cross-breaking. — The superintending officer 

 shall test as many pipes as he may think desirable, for permea- 

 bility, and to resist crushing by cross-breaking. The pipes, after 

 being dried to the satisfaction of the superintending officer, shall 

 not absorb more than 4 per cent, of moisture after being immersed 

 in water for a period of 24 hours. The pipes shall bear a cross 

 breaking strain when supported in a cradle on bearers 18 inches 

 apart, of 1,000 lbs, the weight to bear half-way between the 

 cradle on the upper side of the pipe. Should the results of the 



