Performance studies 

Using our non-destructive drilling resistance digital measurement method, Costain can determine the internal condition of timber constructions. This digital measurement allows for preventative maintenance and captures damaged and rotten timber elements prior to failure.

Using a new digital approach and a matrix mapping system, we offer a non-subjective assessment of the timber structure to provide an accurate reflection of your cooling tower’s structural condition.

Our service uses an advanced microdrill fitted with unique dual motor technology that enables both drilling resistance and feed resistance curves to be measured. The feed curve is virtually unaffected by frictional drag on the needle shaft, making the microdrill at least 30 times more sensitive than previous microdrills.

Sample results

The below graph shows a solid 100mm timber. The measured resistance curves are well above the dotted orange line, the dotted line is the minimum amplitude required for the species of wood within the cooling tower (typically softwood European pine).

The below graph shows a timber with a large area of decay highlighted. You will see that the feed curve has dropped dramatically showing very low resistance within the timber. The second in the rear of the graph is the drilling resistance, this show that it is decayed wood and not a cavity, if a cavity is present both resistance graphs would drop below the minimum amplitude.