Jun 13, 2019 Cold rolling mills show a complex vibration behavior, consisting of natural vibrations of the plant mechanics as well as excitations from the drive or bearings but also vibrations caused by defects. The aim of the monitoring is to detect vibrations that are caused by external excitation or faults.

and 150Hz, is a self-excited vibration phenomena typically occurring in the rear stands of tandem cold mills. It can produce significant gauge variations and even cause strip breaks. 3rd octave mill chatter is characterized by a quickly diverging vertical vibration of the rolls for specific rolling conditions (material, mill speed, forces,

Vibration Types The complex nature of a five stand cold mill prevents the discussion of all steps performed to date to improve performance. We will discuss three basic types we encountered as we began to increase mill speeds: Rumble, Third Octave and Fifth Octave: Rumble Vibration occurring near 100 Hz was encountered during acceleration

Statistical analysis of the rolling parameters during the vibration of the five-cell cold rolling mill was conducted by Makarov et al. [7]. Brusa and Lemma [8] analyzed the dynamic effects in ...

In the present paper Rolling Mill -2 is considered. As this Rolling Mill is older therefore defects such as a) looseness of fasteners and belts, b) mis-alignment of parts, c) wear out of the components such as gear teeth, bushes, couplings and bearings are observed during inspection, which …

Mar 26, 2002 Models for the occurrence of the vibrational instability during rolling known as third octave chatter are presented and discussed. An analysis of rolling mill chatter was performed for the purpose of identifying characteristics of the vibrations and to determine any dependency on the rolling …

Mill chatter in tandem cold rolling mill is a major rejection to the quality and production of the strips. In most mill vibration models, either the roll mass is usually limited to vibrate in vertical direction and vertical-horizontal directions, or the multiple rolls system is simplified to a single mass system. However, the torsional chatter is also a typical type of mill chatter, and the ...

Many customer will only use cold rolling mill, but forget to make routine maintenance of cold rolling mill equipment during usage process. So for life and long-term operating efficiency of the cold rolling mill, it does not do any good.Maintenance of cold rolling mill is related to production quality and equipment life, so during the repair and maintenance work of cold rolled ribbed machine,it ...

Feb 15, 2017 The elastic deformation of rolling mill elements during the rolling process is important. By knowing the displacement of rolls, the optimum gap between the work rolls can be calculated. In present research, a vibration model with two degrees of freedom is proposed for a cold sheet rolling mill and the stiffness parameters of different mill elements are calculated. A numerical simulation and …

On account of the self-excited vibration in No. 5 stand of 1420 cold rolling mill, the relationship between rolling lubrications and self-excited vibration of rolling mill was theoretically studied. The self-excited vibration in No.5 stand of the mill was restrained by optimizing the lubrication technical parameters, and the critical stabilized rolling speed was increased from650 m/min to ...

So it is very necessary to analyze and processing the vibration signals of the working roll to determine the characteristics of the working roll of rolling mill.This paper based on the theory of wavelet transform, in 300 four high reversible cold-rolling mill as research object, using the method of wavelet basis adaptive selection based on ...

Taking the rolling parameters of a 1780 mm hot rolling mill as an example, we analyzed the hysteresis between the dynamic rolling force and the roll vibration displacement by varying the rolling ...

Nov 01, 2020 It was believed that mill chatter during cold rolling is due to abnormal periodic oscillations of the rolls in the vertical direction , . Heidari et al. used an accelerometer located at the top of the stand to detect the vertical movement of the rolling mill. The investigation of the plant showed that when rolling hard and thin strips at high rolling speeds, stands No. 4 and 5 chattered frequently.

However, there are several types of rolling mill vibration that can have a significant impact on the quality and/or productivity of the cold rolling process. The two common forms of rolling mill vibration that are most difficult to solve are third octave gauge chatter and fifth octave chatter.