In the demanding field of structural bolting, Squirtern DTI washers are revolutionizing how installation crews and QC inspectors verify bolt tension. These advanced direct tension indicators provide a clear visual orange extrusion when the assembly is properly tensioned, eliminating guesswork. However, if your Squirtern DTI is not working as expected, that "no squirt" response is not a product failure—it often signals an underlying issue with the steel, the bolting assembly, or the installation method. Proper Squirtern DTI installation ensures structural integrity and safety. For procurement and project managers seeking reliable fastening solutions, explore the FULLERKREG Squirtern DTI collection to find fully compliant components. Should you need immediate DTI washer troubleshooting assistance or specialized project quotes, please contact our expert engineering team at sales@fullerkr.com.
What Is a Squirtern DTI Washer?
- No feeler gauge needed: The visual orange indicator confirms tension instantly, saving valuable time during inspection.
- Weather-resistant indication: The bright orange silicone is designed to withstand harsh field environments without washing away.
- Self-diagnosing (no squirt = problem alert): If the orange material does not extrude, it acts as an immediate diagnostic warning that the bolt, nut, washer, or installation process is compromised.
- Compatible with standard structural bolting: Designed to integrate seamlessly with standard heavy hex high-strength bolts and assemblies.
Squirtern DTI Washer Specifications
Note: Values are per AS 1252 / AS 4100.
| Diameter | No. of Bumps | OD (mm) | ID (mm) | Thickness (mm) | Min. Bolt Tension (kN) |
|---|---|---|---|---|---|
| M12 | 4 | 27.3 | 12.6 | 2.7 | 51 |
| M16 | 4 | 33.6 | 16.7 | 3.3 | 95 |
| M20 | 5 | 40.6 | 20.9 | 3.7 | 145 |
| M24 | 5 | 48.7 | 25.1 | 4.1 | 210 |
| M30 | 7 | 58.4 | 31.4 | 4.1 | 335 |
| M36 | 8 | 70.4 | 37.7 | 4.9 | 490 |
Material and Finish
- Material Grade 8.8
- Mechanically galvanized finish
- ASTM F959M / EN 14399-9 compliance
- Operating temperature -50°C to 40°C
The Three-Step Installation Method
Step 1: Snug
Bring the steel plates into firm contact. Do NOT fully compress the DTI on this first pass; the goal is simply to close the gap between the plies.
Step 2: Squirt
Tension the assembly until the orange indicator extrudes from the bumps. No torque calibration is needed, as the extrusion visually confirms tension.
Step 3: Inspect
Visually verify the orange extrusion on each bump to ensure the minimum required tension has been achieved.
Critical Installation Rules Before Tensioning
- The bumps must always face outward, away from the structural steel.
- Always use a hardened structural washer between the turning element and the DTI.
- Snug the entire bolt array first before applying final tension to any single bolt.
- Do not allow the Squirtern DTI to spin during installation; it must remain stationary.
11 Reasons Your Squirtern DTI Is Not Squirting
| # | Reason for No Visual Squirt | Solution |
|---|---|---|
| 1 | Incorrect hole size or slotted holes | Use an additional round or square washer. M12-M24 holes can be max 2mm over nominal, M30+ max 3mm over. Watch out for chamfered edges that allow the DTI to sink. |
| 2 | Incorrect hardness of flat washer | The flat washer must be min 320 HV (35 HRC). A soft washer causes the DTI bumps to dig in rather than compress properly. |
| 3 | Plate and beams out of square or welding deformation | Assess curvature. Plates must be in full contact. Snug the assembly, then tension systematically from the stiffest part outward. |
| 4 | Bolts breaking in torsion and lube dried out | Apply stick wax to the male threads before installation to reduce rotational friction. |
| 5 | Bolt assemblies exposed to dirt, heat, moisture | Store all assemblies in dry conditions. Avoid using tarps in high humidity, which causes sweating and rapid corrosion. |
| 6 | Orientation of bumps in wrong direction | Bumps must always face away from the steel. Never place the turning element directly against the bumps; always use a hardened structural washer. |
| 7 | Squirtern DTI not squirting at expected tension | Calibrate the assembly in a Skidmore-Wilhelm before installation. Check the gap with a feeler gauge, and test in solid steel twice to verify performance. |
| 8 | Squirtern DTIs not evenly compressed | Snug the entire array first. Don't fully compress the DTI on the snug pass. Tension from the most rigid point outward. |
| 9 | Squirtern DTI spinning during installation | Hold the washer stationary. Spinning grinds the bumps and wears away the orange indicator before it can extrude. |
| 10 | Bolts breaking prior to minimum tension | Add stick wax to both the bolt threads and the nut face to significantly reduce friction. |
| 11 | Powered torque tool stalling | Check bolt storage (dry only). White rust on galvanized bolts severely increases friction. Proper lubrication is absolutely critical. |
Gap Measurement for Long-Term Verification
While the visual orange squirt is the primary indicator, post-installation verification can be achieved using a 0.13mm feeler gauge.
- Ensure the assembly is fully tensioned and the orange extrusion is visible.
- Attempt to insert the 0.13mm feeler gauge into the gap between the DTI bumps.
- Check multiple gaps around the circumference of the washer.
- If the feeler gauge is refused at the required number of gaps, the minimum tension has been verified.
Key Principle: Torque Is Not Tension
It is critical to understand that torque (Nm) and tension (kN) are fundamentally different. Torque is the rotational force applied, while tension is the clamping force achieved. Torque values are not published for structural assemblies because torque cannot reliably verify installation due to wildly varying friction conditions. A Squirtern DTI visually indicates correct tension, entirely bypassing the unreliability of torque measurement.
Storage and Handling Best Practices
- Keep all fastener components in dry, covered storage.
- Avoid placing tarps directly over kegs in high humidity to prevent sweating.
- Ensure pre-installation lubrication is intact; re-lubricate if dry.
- Inspect components before use to ensure no severe white rust or debris is present.
FAQ
-
Why is my Squirtern DTI not squirting?
This is typically a diagnostic alert indicating excessive friction, dry lubrication, soft flat washers, or un-square steel joints. Refer to the 11-point troubleshooting table above. -
Can Squirtern DTIs be used with oversized or slotted holes?
Yes, but you must use an appropriately hardened additional round or square washer to prevent the DTI from sinking into the hole. -
How do I know if my flat washer is hard enough?
Your structural flat washer must be certified to a minimum hardness of 320 HV (35 HRC) to prevent the DTI bumps from embedding into it. -
What is the correct feeler gauge thickness for Squirtern DTI verification?
A 0.13mm feeler gauge is used for post-installation DTI washer gap measurement. -
Can I reuse a Squirtern DTI washer?
No. Once a Squirtern DTI has been compressed, it has permanently deformed and cannot be reused under any circumstances. -
Where can I get Squirtern DTI washers with installation support?
You can purchase compliant, high-quality indicators directly from the FULLERKREG Squirtern DTI collection. For technical installation support, email us at sales@fullerkr.com.
Conclusion
When properly installed, Squirtern DTIs provide foolproof verification of structural bolt tension. Remember, "no squirt" is not a failure of the washer; it is the DTI's most valuable diagnostic feature, alerting you to an installation or material problem before it compromises the joint. Equip your field crews with the best indicators available.
Shop FULLERKREG Squirtern DTIs
Email us at: sales@fullerkr.com