The grey forecast is one of the important parts in grey systems theory. According to the theory of prior using of new information, based on the present theories of buffer operators and some already existed weakening buffer operators, some new weakening buffer operators are established. Meanwhile, they are compared with the existing weakening buffer operators in effectiveness. The problem that there are some contradictions between quantitative analysis and qualitative analysis in pretreatment for vibration data sequences is resolved effectively. The research result shows the kind of new weakening buffer operators increase the forecast precision of grey forecast model remarkably.