60 DEPARTMENT BULLETIN 12 16, U. S. DEPT. OF AGRICULTURE 
7. Where tank cars, distributors, or barrels are being filled, samples may 
conveniently be taken from the pipe line through which the material is flowing, 
as hereinafter described. 
(A) WHEN MATERIAL IS PUMPED UNDER PRESSURE 
8. The sampling pipe shall be inserted into a rising section of the pipe line on 
the discharge side of the pump. The sampling pipe shall be not more than 
one-eighth the diameter of the line pipe and its opening should be turned at an 
angle of 90° facing the flow of the liquid. This pipe shall be provided with a 
plug cock and shall discharge into a receiving drum of 50^gallon capacity. 
The plug cock shall be so adjusted that there is a steady continuous flow of 
bituminous material through it and shall be so regulated that the receiver will 
fill in the same time that is required to make the entire pumping. In the case 
of semisolid materials, the receiver shall be provided with a steam coil which 
shall keep the contents at a temperature just above the liquefying point. 
At completion of the pumping, the receiver shall be thoroughly agitated, and a 
1 -quart sample taken therefrom. The sampling shall be so regulated that for 
each 1,000 gallons of material pumped, at least 1 gallon of sample is taken ; but 
40 gallons shall be the limit required for any one cargo. 
Care should be taken that the drip cock, after once having been set, allows a 
constant flow during the pumping. 
This method is also applicable to gravity flows where the pipe line is completely 
filled by the outflowing liquid and has a rising section. 
(B) WHEN MATERIALS FLOW BY GRAVITY 
9. Materials flowing by gravity through pipes which are not completely filled 
may be sampled by taking dipperfuls at the outlet at frequent and regular inter- 
vals. These samples shall be combined and the total sample shall be not less 
than 0.1 per cent of the whole material. The samples shall be collected in a 
receiver and resampled as described in section 8. 
SAMPLING AT POINT OF DELIVERY 
10. Samples may be taken by means of a weighted bottle or can, as described 
in section 6, or from the unloading pipe line as described in section 7. 
Liquid bituminous materials shall be sampled before heating. Semisolid or 
solid bituminous materials shall be rendered fluid by heating. Sampling should 
be so conducted as to eliminate the possibility of adventitious water resulting 
from leaky steam heating coils, rain, or snow. 
11. Samples may be taken from distributors by means of a weighted bottle 
or can, as described in section 6. One sample shall be sufficient. 
12. {a) Semisolid or solid materials. — Where the lot of material to be sampled 
is obviously from a single run or batch of the producer, one package or cake 
shall be selected at random and sampled as described in the following para- 
graph. Where the lot of material to be sampled is not obviously from a single 
run or batch of the producer, or where the single sample selected as described 
above fails on test to conform to the requirements of the specifications, a num- 
ber of packages or cakes shall be selected at random equivalent to the cube root 
of the total number of packages or cakes in the lot. For convenience, Table 6 
is given. 
Table G. 
-Number of samples of bituminous material to deselected for shipments 
of various sizes 
Packages or cakes 
in shipment 
Packages 
or cakes 
selected 
Packages or 
cakes in shipment 
Packages 
or cakes 
selected 
2t08 _ 
2 
3 
4 
5 
6 
217 to 343 
7 
9 to 27 
344 to 512 
8 
2Hto64 
513 to 729 
9 
65 to 125 
730 to 1,000 
10 
126 to 216 
1,001 to 1,331 
11 
