A steel rolling mill customer had requested us to develop a rolling oil to roll stainless steel in a new 3-stand 18-high rolling mill and demonstrate its performance on an experimental set up. The present paper describes the methodology adopted to assess the suitability of a rolling oil for the particular rolling mill.
The vertical vibration mechanism of cold rolling mill is studied under the influence of the dynamic friction mechanism between the workpiece and roll. Fan et al. introduced the Duffing oscillator and the parameters of the excitation system and established the roll system vertical vibration model . The bifurcation characteristics of the rolling ...
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 ...
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,
Abstract The article considers the nature, occurrence mechanism and development of resonant vibrations found in the working stand equipment of cold rolling mills during the production of strips with a thickness of 0.4–0.6 mm at speeds of more than 12 m/s. Vibration causes are possibly based on changes in the metal properties during rolling due to …
rolling mill coupling vibration. Yun et al. [ ] proposed a model which allows rolls to vibrate along two orthogonal directions to study the vertical-horizontal coupling vibra-tion and suggested that mode coupling might also induce vibration. Since the vibration of a high-speed rolling mill always appears as the coupling of multiple vibration types,
Layout of a 5-stand tandem cold rolling mill. Chatter can be regarded as a type of self-excited vibration. Because interactions occur between the structural dynamics of the mill and the rolling process, this phenomenon is subsequently observed when the external excitation force changes the roll gap and rolling speed.
The rolling mill vibration is characterized by the coupling effects among mechanical, electrical, hydraulic and interfacial subsystems. The influence of the mill modulus control gain in automatic gauge control on the vibration in hot rolling mills was investigated. Firstly, an experiment related to the mill modulus control gain was carried out in the hot …
Thread Rolling Figure 13.16 (a) Features of a machined or rolled thread. (b) Grain flow in machined and rolled threads. Unlike machining, which cuts through the grains of the metal, the rolling of threads causes improved strength, because of cold working and favorable grain flow. Figure 13.15 Thread-rolling processes: (a) and (c) reciprocating
Our blog ' Mill Vibration Phenomena during Cold Rolling ' describes the different modes of mill vibration. Third octave gauge chatter and fifth octave chatter are two common forms of mill vibration that are difficult to solve. Both can cause significant strip quality issues if …
Then tandem cold mills (TCM) from SMS group are the most efficient option for you. Designed in 4-high or 6-high configurations, they feature our well-known CVC ® plus as well as other cutting-edge rolling technologies. Here you will experience the latest developments in cooling, strip-edge control, and roll bending to ensure excellent strip ...
Zheng et al. (2017) established a spatial vibration model of a six-high cold strip rolling mill based on multi-body transfer matrix method, and demonstrated the vibration characteristics of the mill. Recently, several attempts have been made to analyze chatter characteristics in tandem rolling mills, especially the effect of friction on vibration.
Keywords: rolling mill vibration, coupling dynamic model, AGC, mill modulus control gain. 1. Introduction The mill vibration has become a bottleneck in the thin steel strip manufacturing [1, 2], as the mill vibration can cause unacceptable product quality degradation in the steel strip, and even severely damage the mill equipment [3, 4].
Gong et al. made a numerical simulation of the roll vibration during the cold rolling in 6-roll mill, and through the analysis of the results, it was considered that the vibration had the minimum value when the rolling speed was 25 m/s. With the further improvement of the flatness standard on the market, as the most mature high-precision cold ...
Due to this issue, along with the nonstationary character of rolling and rolling mill load regime, rolling with tension may transform into rolling with pressure, which results in enhanced energy consumption, while a rapid change in rolling with pressure and tension may lead to the emergence of adverse self-excitation vibrations on cold rolling ...
The mill vibration data was collected from the UCM cold rolling plant. It was believed that mill chatter during cold rolling is due to abnormal periodic oscillations of the rolls in the vertical direction [34], [35]. Heidari et al. [36] used an accelerometer located at the top of the stand to detect the vertical movement of the rolling mill.
The vertical vibration often occurs during the rolling production, which has an influence on the accuracy of rolling mill. In order to effectively suppress the vertical vibration of the rolling equipment, the rolling mill model with vibration absorber device was established. Based on the main resonance singularity of the rolling mill system, the best combination of opening …
chatter vibration can affect both the quality and production capacity of cold rolled steel if it is not properly monitored and reduced. 3rd order octave chatter is a self-generating resonance...
The presence of several rolls in cluster cold rolling mills makes on-line vibration monitoring and failure analysis difficult. The dynamic behaviour of rolls strongly depends on the rolling pressure in the roll bite. Strip vibration applies a dynamic component on the rolling force acting on the work roll and may excite the resonance of the mill ...
elastoplastic deformation during cold rolling and its surface quality. MODEL DESCRIPTION In order to reveal the mechanism of defects occur-rence on the surface of steel cold rolled strips during work rolls vibration, the finite element method imple-mented in the DEFORM-2D program was used. The 4th stand of the 5-stand mill 1700 of PAO Severstal ...
Mill vibrations (chatter) especially occurring at high rolling speeds affect product quality of the cold-rolled material and thus lead to yield losses and quality issues. Among other supportive measures active chatter damping has turned out to be an effective approach to counteract these problems by significantly reducing vibration issues of ...
The vertical vibration often occurs during the rolling production, which has an influence on the accuracy of rolling mill. In order to effectively suppress the vertical vibration of the rolling ...
Chatter vibrations were investigated for the high speed 5 stand 4-h tandem cold rolling mill 2030 of the NLMC. Real-time chatter vibration monitoring and diagnostics system was developed and ...
A basic theory of chatter in. cold rolling is presented which is based on the effect of the variable scrip tension on the rolling force as well as on the variations of contact length The structure of a computer program simulating chatter of a tandem mill is presented and examples given of the effect of rolling speed, strip width, coefficient of friction and of using a tuned damper.
The cold rolling process is a high speed, transient, and time-related metal machining molding process [1]. As cold rolling mill is a multimass and rotary motion object system, the vibration as an implicit factor commonly exists in the course of its operation, but it usually does not apparently present due to the conditional constraints of ...
The rolling process is determined by the interaction of a number of different movements, during which the relative movement occurs between the vibrating roll system and the rolled piece, and the roll system's vibration interacts with the strip's deformation and rigid movement. So many parameters being involved leads to a complex mechanism of this …
The vertical vibration mechanism of cold rolling mill is studied under the influence of the dynamic friction mechanism between the workpiece and roll. Fan et al. introduced the Duffing oscillator and the parameters of the excitation system and established the roll system vertical vibration model [ 12 ].
Rolling mill vibration is a technical problem in the iron and steel industry for many years and has serious impact and harm on production. There were serious vibrations in the middle mills when rolling thin container strip for the compact strip production (CSP) strip hot rolling process. This paper studied the hysteretic characteristic of rolled strip and established …
Dynamic behaviour of cold rolling mill with unsteady lubrication roll-gap interface during sheet... 00:00:00 This paper presents the results of developing a vibration model for the rolling mill vertical system with respect to the roll gap under the unsteady lubrication conditions to address the frequently self-excited vibration ...
In common with other rotating machines, rolling mills are prone to many different vibrations during rolling and most do not cause a problem. However, there are several types of rolling mill vibration that can have a significant impact on the quality …
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