Squirter® DTI FAQs

How to inspect Squirter® DTIs

Inspectors should inspect squirter® DTIs by observing the volume and appearance of the silicone which has emanated from the compressed squirter® DTI's. Tests have shown that after proper calibration, the visual appearance of squirted silicone is a very accurate indicator of proper DTI bump compression, even better than a feeler gage.

For more data on squirter® accuracy:
Leave your Feeler Gage at Home,
Squirter® DTIs are Amazingly Accurate,
Squirter® Blind Tested at University of Idaho

Inspectors can tell which of these bolts has been tensioned correctly, at a glance. Click the image to see how easy Squirter® DTI's make your inspection job.

For more rigorous inspection, we suggest the following inspection specification:

The Inspector should observe the Squirter® DTI's calibration exercise at the beginning of the project. Ensure correct bolt tension on the skidmore or that the residual DTI gap has been closed sufficiently at the intended squirt appearance.
In the first few hundred bolts tightened using Squirter® DTIs, check either that the same squirted silicone volume and appearance has occurred or if the silicone has blown or washed away, that the feeler gage will not enter the DTI gaps half way around (that is, for a five bump DTI, three places) on about 10% of the bolts.*

*Note: Inspectors will quickly realize that observing the squirted silicone gives them the capability for 100% bolt inspection by visual examination.For this reason it is important that the inspector follows the bolting crew closely, perhaps on the same or next day.

If for any reason the inspector is not certain that the correct amount of silicone was squirted out during installation, a feeler gage of the correct thickness can be used to check bump compression.

In situations where the inspector finds the feeler gage is allowed entry more than half way around the DTI and yet there is some silicone showing (see How Long Does the Silicone Last) the inspector should request a test to determine whether the bolt has been correctly tensioned even though the DTI bumps might not be completely crushed according to a feeler gage.

<< Back to FAQ Index