High strength friction grip (HSFG) bolts vs. normal bolts
HSFG bolts have the following benefits when compared with normal bolts:
(i) Performance of preloaded HSFG bolts under fatigue loading is good since the pre-stressed bolts are subjected to decreased stress range during every loading cycle when compared with unloaded bolts.
(ii) For structures adjacent to machinery that produce substantial vibration, preloading bolts can help to avoid the loosening of bolts.
(iii)HSFG bolts are used in connections where any slight slip movement would reduce the integrity of whole structures break down.
(iv) Because of its high tensile strength, it's commonly used in connections that require the taking up of high flexure and tensile stress produced could be readily resisted by it high tensile strength.