Hylec Controls announces the launch of two new automatic penetrometers
by LBG designed for testing wet mortar. The new devices help determine the
consistency of wet mortar, or similar materials by measuring the penetration
force of a specified needle into the sample material.
LBG’s new automatic penetrometers use a single electromechanical control
system to ensure that the needle penetrates the mortar at a fixed speed. The needles
are shaped appropriately to ensure a constant friction surface.
The single needle model is used for testing cement paste (mortar without
sand) and has a 5kg load cell connected to the needle to measure the
penetration force at a penetration speed of 3mm/hour over a maximum test time
of 12 hours.
The 4-needle version is used for testing cement paste with sand and has
a 3kN load cell connected to each needle to measure the penetration force at a
penetration speed from 1.5mm/hour to 30mm/hour. A pneumatic system in each
needle disengages it once it reaches a force of 3kN. The four load cells
measure the consistency in a single sample with their average reading giving a
better result on sand mixtures than a single needle due to consistency variations
in the sample.
The 4-needle penetrometer is particularly useful for testing concrete
spray used for tunnel lining. This system enables a graph of the penetration
force versus time to be captured and displayed on a computer screen, allowing
the setting time of the mortar to be predicted.
According to the manufacturer, LBG, this method of predicting the
setting time of mortar is more accurate than the traditional Vicat method where
a needle is repeatedly pushed into the setting mortar with a fixed force, and
setting time is determined when the needle is unable to penetrate a pre-set
LBG’s new automatic penetrometers are being used by several well-known
European cement manufacturers and cement additive manufacturers. The new
devices far exceed the accuracy in force measurement or control of penetration
speed in existing manual penetrometers.
LBG is part of a long established Italian group of companies specialising
in the field of materials testing.