A Rhode Island Safety Alert
Good Day CARES Subscribers: Following are deficiencies in the Sartori Twister/1001 Nights Manual, regarding ONLY the 14 vehicle bolts and nuts:
- Grades of bolts and nuts are not specified.
- Tightening specs (torque chart) not provided.
Consequences arising from the above deficiencies
- As years go by, bolts and nuts are replaced in routine maintenance. Bolts and nuts must be replaced in kind (grade 8.8 for 8.8 and 10.9 for 10.9). Replacing with higher grade, and tightening to the higher grade may damage the plates being mated or connected. However, the worst case scenario inspectors must watch for happens if an operator changes a bolt to a higher grade and fails to replace the nut with a new nut compatible with the higher grade. If the operator tightens to the higher grade standard, the original grade nut will be damaged and will eventually fail under this worst case scenario. Therefore any replacement other than in kind must be done in strict coordination with the manufacturer.
- Because the amount of tightening (torque) is not specified, some operators may conclude that the intent of the manufacturer is for them to follow a "tighten as much as you can" standard. Such a standard for tightening will eventually damage the nuts. A damaged nut deteriorates over time and will eventually fail completely. At such point, it would be simple to get the bolt out by hand since a failed nut is equivalent to a missing nut. Please make sure tightening standards are available and are never exceeded.
- An Operator might go to the internet to get tightening specs (torque values) for the bolt size and grade. Even if he does that, he will be overtightening. The generic internet values will most likely be for a different applications (e.g. buildings, which are never subject to multiple assembly/disassembly or to repeated dynamic forces). Sartori validated this issue when they sent two sets of torque value according to the particular application. One set was for Frequent Assembly/Disassembly, and the other for Rare assembly/disassembly.
Please ask the jurisdiction(s) you work with to contact the manufacturer directly and obtain All the information they perceive as missing from the Manual.
The attached diagram and charts, as well as an e-mail, all from Sartori, are the information Rhode Island obtained from the manufacturer on the Vehicle Bolts and Nuts ONLY. Please do not rely on this information as it may not be complete and/or sufficiently accurate. This serves only as an Alert that Safety Critical information are missing from the Manual and must be obtained directly from the Manufacturer.