Humboldt H-4167 Voluvessel - Manual (Page 3)

This unit has been calibrated and is ready for use as received.
After set-up, calibration is recommended.
Calibration Check:
Verify the procedure to be used and the accuracy of the volume indicator by using the
apparatus to measure containers or molds of determinable volume that dimensionally
simulate test holes that will be used in the field. The apparatus and procedure shall be
such that these volumes will be measured to within 1.0 percent. Containers of different
volumes shall be used so that calibration of the volume indicator covers the range of
anticipated test hole sizes.
Note: The H- 4141 four-inch mold and the H-4161 six-inch mold described in ASTM
D698 and D1557 test for moisture/density relations of soils or other molds prepared
to simulate actual test holes may be used. Where several sets of apparatus are
used, it may be desirable to cast duplicates of actual test holes. These sets should
represent the range of sizes and irregularities in the walls of the test holes that will
be encountered. These fabricated holes call be used as standards for the calibration
check of the Voluvessel. This can be accomplished by forming plaster of Paris
negatives in the test holes and using these forms as forms for Portland cement
concrete castings, after removing the plaster of Paris negative from the concrete
castings, the inside surface of the fabricated holes should be sealed watertight, and
their volume determined as indicated.
Method to obtain volume of container or mold to be used to
check the accuracy of the voluvessel:
Determine the mass of water, in grams, required to fill one of the containers. Slide a
glass plate carefully over the top of the surface of the container in such a manner as to
ensure the container is filled completely with water. Determine the temperature of the
water in the container. A thin film of cup grease smeared on the top surface of
the container will make a watertight joint between the glass plate and the top of the
container. Calculate the volume of the container in cubic feet (or cubic meters) by
multiplying the mass of the water, in grams used to fill the container by the unit
volume of water, in milliliters per gram, at the observed temperature taken from
Table 1, and dividing the result by 28317 ml/ft 3 (or 1 x 10 (6) ml/m 3 . Repeat this
procedure until three values are secured for the volume of the container having a
maximum range of variation 0.0001 ft 3 or (2.8 x10(-5) m 3 ), Repeat this procedure for
each of the containers to be used in the calibration check.
Calibration check tests
Place the rubber-balloon apparatus on a relatively smooth horizontal surface.
Pressurize it to 5psi and then adjust the water level up or down until it's at
zero on the scale. Transfer the apparatus to one of the containers and take the
reading on the volume indicator when the rubber balloon completely fills the
container (Notes 1 & 2).
Apply pressure to the liquid in the apparatus until there is no change indicated,