The term "Thread Locking" is used for methods of ensuring the threads stay in place without loosening. In some cases, the frictional forces from bolt axial preload are enough to hold the fastener together. In other cases, we need to use thread lockers. Thread locking can be separated into the following categories. Usage of mechanical parts to prevent loosening, further by increasing the coefficient of friction in the thread to prevent loosening, and finally by using adhesives in the thread to prevent loosening. This contribution describes analytical and experimental evaluation of untightening torque of bolted joints using Loctite thread lockers depending on surface degreasing quality.