??O-rings during assembly drawing, mainly in order to meet the current application, though, O-rings through the initial leak test and also use up to several weeks, but for the damaged o-ring is not possible The rubber o-rings often fail mainly to test the need.

??Therefore, during the installation and initial stress test, O-ring must be undamaged.

??This means that the O-ring must be damaged during use, i.e. after it has been installed in the slot, which is very rare in a static O-ring seal in the case. This type of damage usually used can be traced to one or two reasons.

??The most common use of the O-ring damage because tear, it is reduced from the initial point spread of torque. In this case, part of the O-ring is installed with crushed metal parts, usually generated when an unexpected pop groove during installation.

??In this way damage the O-ring will show obvious signs of mechanical damage, including: portion is severely crushed, O-ring on one part is missing, there is a semicircular cross-section of resection.

??Under normal circumstances, the failure of certain tests o-ring does not reflect any evidence of tightening damage is mainly a tightening of fluorine rubber o-ring through the beginning of the experiment and damage during use, it is because the rubber o-ring damage beginning spread tightening results.