A Fabory customer was experiencing galling in stainless steel bolted connections. Following its client’s instructions, Vaseline was manually applied to the stainless steel bolts as a lubricant, but the fasteners continued to seize too frequently.
Fabory proposed Lubrinox as an alternative. To demonstrate how it performed in practice, Lubrinox and Vaseline were compared under controlled conditions using Fabory’s friction test bench.
Results at a glance
~0.26
Friction coefficient measured with Vaseline, with a variation of approximately ±0.05.
~0.12
Friction coefficient measured with Lubrinox, with a variation of approximately ±0.04.
9 tests
Each test used a fresh stainless steel bolt, nut and washer.
The challenge: galling in stainless steel bolted connections
Galling, also known as seizing, can occur when stainless steel mating surfaces come into high-force sliding contact. The threaded surfaces can effectively cold-weld together, preventing the fastener from being tightened or loosened without damage.
In this application, the customer had been manually applying Vaseline to the stainless steel bolts to prevent the problem. Despite this, the bolts continued to seize too frequently, so an alternative solution was required.
Testing Lubrinox against Vaseline
After discussing the application with Fabory, the customer proposed using Lubrinox fasteners to its client. The client agreed to consider the alternative provided Lubrinox could demonstrate better performance than Vaseline in practice.
To compare the two approaches, tests were carried out on Fabory’s friction test bench.
How Fabory conducted the friction tests
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The results: lower and more consistent friction with Lubrinox
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The bolts tested with Vaseline showed a higher and more variable friction coefficient of around 0.26 (±0.05). In comparison, the Lubrinox bolts showed a substantially lower and more stable coefficient of around 0.12 (±0.04).
Under the tested conditions, the lower and more consistent friction provided by Lubrinox effectively prevented galling.
“Thanks to this low and consistent friction, galling was effectively prevented.”
Dominic Franse
Manager Engineering, Fabory
Why manual lubrication can introduce variation
The tests also showed greater variation in friction within the thread than underneath the bolt head.
Fabory observed that this was likely linked to manual lubricant application. Manually applied lubricant is not always distributed evenly and can move during assembly, which can influence friction behaviour.
Lubrinox incorporates a lubricating coating into the fastener itself, removing the need to apply a separate loose lubricant during assembly.
The result: a complete switch to Lubrinox
The test results gave the customer the evidence needed to demonstrate Lubrinox to its client. Following the comparison, the client agreed to switch entirely to Lubrinox fasteners.
The change removed the need to manually apply Vaseline to the bolts and provided lower, more consistent friction under the tested conditions.
For this application, Lubrinox offered a practical solution to the recurring galling problem while simplifying the assembly process by removing a manual lubrication step.
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Lower and more consistent friction Looking to reduce galling in stainless steel bolted connections?Lubrinox combines stainless steel fasteners with an integrated lubricating coating, helping reduce friction and remove the need for separately applied lubricant during assembly.
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