Squirter® DTIs
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Are all your bolts tight or did you forget one?SQUIRTER® DTIs visual quality control -see when your done!! 3 Easy Steps:1. Calibrate in a skidmore2. Snug the array of bolts 3. Drive it 'Till It Squirts |
Pre-Installation Verification Test Report
using Direct Tension Indicators: 
1.
Calibrate Squirter® DTI's as follows:
Before starting installation, Squirter®
DTI's MUST be calibrated in a skidmore or in solid steel by checking the
DTI gap with a feeler gage.
In a Skidmore -- Insert a bolt, nut, flat washer, and Squirter® DTI. Tighten the assembly to about 10% to 20% over the minimum required tension with any wrench in about five to ten seconds, just as the bolt would be tightened in the steelwork. eg for a 7/8" A325 bolt, about 45,000lbs.
View our Squirter® DTI Calibration Video
Download Installation PDF
Once tightened, note the appearance, flow volume, and number
of squirts emanating from under the DTI at that tension. The squirt should
look similar to 
this
photo. The number of squirts should be AT LEAST equal to the number of
bumps on the DTI less one: for instance, a five bump DTI should squirt
in at least four places. Repeat this test a few times and get a visual
impression of how much squirt is necessary. To be a Squirter® "Pro",
cover the dial of the skidmore and see how close you can get to the calibration
tension.
In solid steel -- Duplicate the above test in a solid connection, tightening the bolt assembly until the DTI has been sufficiently compressed so that a feeler gage of the correct thickness (.005" if the DTI is on the nut end, or .015" if the DTI is under the head) WILL NOT enter HALF of the available places right into the bolt shank. If it does, tighten the bolt a little more and note the silicone squirt volume and appearance. Repeat this test a few times and get a visual impression of how much squirt is necessary.
2.
Snug the Array
Always snug an array of bolts before final tightening. Make sure you don't fully compress the DTI on the snug (first) pass. On the final pass, compress the DTI's from the most rigid point outward.
3.
Drive It 'Till It Squirts
TIGHTEN THE BOLT UNTIL AFTER THE ORANGE SILICONE APPEARS IN VOLUME FROM MOST OF THE DTI'S SQUIRT LOCATIONS*. DON'T STOP TIGHTENING UNTIL THE SQUIRT VOLUME AND APPEARANCE IS JUST LIKE IT WAS IN THE CALIBRATION EXERCISE. THEN STOP TIGHTENING.
* Each DTI has one squirt location for every bump. The number of squirts should be AT LEAST equal to the number of bumps on the DTI less one. For instance, a five bump DTI should squirt out in at least four places.
How to inspect SQUIRTER® DTIs? SQUIRTER® DTIs Inspection instructions are here
Note 1: For ASTM A325 and A490 bolts, as determined by the RCSC, minimum tension is 70% of minimum tensile strength. See what bolt tension is needed. Other bolt grades may require different minimum tension.
Note 2:
Use of DTI Washer in Accordance with ICC Specifications
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