Home 24850 torque speed characteristics of rolling mills
Flat Rolling •Roll Force: F= LwY avg •Roll-strip contact length L •Average strip width w –despite the fact that spreading, or an increase in width, may actually occur if edger mills are not used •Average true stress of the strip in the roll gap Y avg •Assumes no friction and thus predicts lower roll force than the actual value
cold rolling mill in the Gwangyang Works of POSCO. For the experimental study, the acceleration of the roll, rolling force and speed of the work roll were measured by acceler-ometer, load cell and tachometer, respectively. The numeri-cal model of the rolling mill including the driving system was built for multibody dynamic analysis. The model was
h)Draw the speed-torque characteristics of a three phase induction motor in its 4-quadrant region. i)Why regenerative braking is not preferred for dc series motor ? j)Plot the torque-speed characteristics of dc shunt motor during dynamic braking. . 2.a) Derive the formula for overloading factor, when a motor is subjected to i) short time duty
This paper proposes a method capable of reproducing the particular operating conditions of a hot strip mill and predicting the evolution of the main electrical variables from both the characteristics of the steel to be milled and the specific features of the rolling mill. The method analyzes the load torque and the motor-speed evolution in the stands of the roughing and …
1.Torque and armature current characteristics: In case of a series motor, the series field winding is carrying the entire armature current. Flux produced is proportional to the armature current. The torque in case of a dc …
4.2.3.1.1 Roll Mills. The roll mill is the simplest batch mixing equipment. The principal design consists of two horizontal rolls, usually of equal size, arranged side by side and rotating toward each other at different speeds. The ratio of the peripheral speeds of the rolls, known as friction ratio, ranges from 1 to 2 but is usually around 1.2.
1.4.4 Hot and cold rolling and recrystallization 15 1.5 Classification of Rolling Mills and Rolling Stands 17 1.5.1 Classification 17 1.5.2 Rolling mill stands 20 1.5.3 Roll arrangement in mill stands 20 2. Mechanics of Rolling 30 2.1 Characteristics of Rolling 30 2.1.1 Draught and reduction 31 2.1.2 Elongation 31 2.1.3 Spread 32
torque stabilization by to the effect on speed of the previous, further or controlled mill stand. The tension control accuracy depends on how exact the unhindered rolling torque is determined.
FIGURE 1 Induction motor torque-speed characteristic curves.. Figure 2 showed the equivalent circuit for the stator. We can simplify our calculations by replacing it with a Thevenin's equivalent so that we do not have parallel branches in the …
The speed-torque characteristics of different DC motors are as shown in the below figure. In DC series motors, torque increases as the square of armature current. Hence these motors are used in high starting torque and variable speed applications. In DC shunt motors, torque is directly proportional to armature current. It is a constant speed motor.
Power requirement is very high. Speed control ratio is 1:10. Very low creeping speeds of 1 rpm may be required. Starting torque should be in the range 200 to 250% of full load torque. The acceleration of the drive should be completed in about 15 s. For small periods an overload capacity of 200-250% may be required.
It is important to study the vibration of rolling mills to improve the stability of rolling production. A dynamic rolling process model is established by considering the elastic recovery of the exit strip and the influence of multiroll equilibrium, and the accuracy of the model is verified by experimental data. On this basis, based on the distribution of friction force in the deformation …
torque speed characteristics of rolling mills. Cold rolling mills are an important part, speed Roll force, torque, temperature CVC, HS, position, and the characteristics of the fric-excell sheet calculation torque speed power for rolling mill, Here is a handy calculator that lets you specify different drive train characteristics » Learn .Torque in rolling mills calculation formula with ...
Torque - Speed Curves One commonly used method of displaying motor characteristics graphically is the use of torque - speed curves. While the use of torque - speed curves is much more common in technical literature for larger DC machines than it is for small, ironless core devices, the technique is applicable in either case. Torque - speed
Mechanical characteristics- speed- torque characteristics of various types of load and drive motors - braking of electrical motors-dc motors: shunt, series, compound motors-single phase and three phase induction motors Unit-III Starting methods Types of d.c motor starters-typical control circuits for shunt and series motors-three phase squirrel ...
In the design of piecewise rolling mills for seamless pipe, careful attention is paid to overloading and dynamic decrease in speed of the drive motors, since the rolling torque depends directly on the roller speed and so slight decrease in motor speed may greatly lower the load in transient conditions.
tension, speed Roll force, torque, temperature CVC, HS, position bending Coil-data Operator-trims Scheduling 400 350 300 250 200 150 100 50 0 0 0.5 1 1.5 2 Log deformation Yield stress 3542 Rolling mill applications covered by ABB include: Single and multistand Mills Cluster and Sendzimir*) Mills Inline and continuous rolling mills Reversing ...
John G. Lenard, in Primer on Flat Rolling (Second Edition), 2014 2.7 Generation III – Coil Box Hot Strip Mills. In the 1970s, Stelco of Canada developed the hot coil box designed for installation in hot strip mills ahead of the finish mill for coiling the transfer bar from the roughing mill and uncoiling it into the finishing mill. The coil box reduced the distance between the roughing mill ...
Fig.5. Frequency response characteristics of the rolling mill at change of the speed setting for the first stand (1,2- for rolling speed 1.78 m/s, 3,4- for rolling speed 17.8 m/s; 1,3- for the first inter-stand gap, 2,4- for the second inter-stand gap).
Mechanical characteristics- speed- torque characteristics of various types of load and drive motors - braking of electrical motors-dc motors: shunt, series, compound motors-single phase and three phase induction motors Unit-III Starting methods Types of d.c motor starters-typical control circuits for shunt and series motors-three phase squirrel ...
This process is vastly used in respect of any other rolling process. In this process, the metal is heated above the recrystallization temperature.In the hot working process, the metal is changing its grain structure because of the heat, now there were a new set of strain-free grains in the metal and this process needs less amount of force which correspondingly reduces the quality of the ...
technology for rolling mill applications. As a result, TMEIC provides customers with an unparalleled choice of technology, including: 1. Proven AC drive solution for each type of rolling mill application, ranging from large torque, slow-speed roughing mills to the high-speed, wide tension range aluminum foil mills. 2.
Series, which is optimized for the particularly high torque requirements in cold rolling mills. Reliable torque transmission from input to output at the highest torque capacity is the most important characteristics of Voith cardan shafts. However the drive configurations of cold rolling mill stands vary, ranging from reversing single stands on
Characteristics of Rolling Mills with Roll Shifting ... The effects of strip width, reduction, and rolling speed on strip shape taking WRC and WRS into consideration are discussed ...
Rolling mill DC motors are best at low speed, high torque applications, while AC motors typically need to run above 800 rpm to be cost effective. To handle this most drive manufacturers offer ...
1.4 Roll torque and power: Roll torque can be estimated from the rolling force. Torque is equal to force multiplied by the radius at which the force acts. We can assume that the roll force is acting perpendicular to the strip at a radius equal to one half of the projected arc lengt h of contact. For each roll, the torque is: T = FL/2 Roll power ...