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2026. 6. 30. 작업

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"Always Replace" (torque-to-yield) Bolts

처리 내용

I cannot tell you directly if the bolts you are using are Torque to Yield (TTY or T2Y) bolts, but if Bently says to replace them, you bet I'd do it. What are three bolts in comparison to the well being of your family and yourself, not to mention those around you should any of these bolts fail? As for T2Y bolts, here is what Fel-Pro says about them : T-T-Y head bolts are engineered to stretch within a controlled yield zone. Once they reach this zone, they are designed to spring back to provide a more precise level of clamping force. This stretches the bolts into their elastic range, and in some cases, the stretching approaches the bolts’ elastic limit, permanently stretching it. Once the yield zone is reached, the clamping force will be more consistent. Getting the to the precise yield zone (for maximum clamping force) is accomplished by tightening bolts to a certain torque spec, then turning the bolts an additional number of degrees. It goes on to say: Since T-T-Y bolts are designed to