Grinding mill critical speed grinding mill critical speed calculation ball mill critical speed mineral processing metallurgy the critical speed of a rotating mill is the rpm at which a grinding medium will begin to "centrifuge", namely will start rotating with the mill and therefore cease to carry out useful work.

Principles of Grinding in Ball Mills | Orbis Machinery, LLC.

Oct 26, 2018 · Faster RPM are required for smaller mills to reach critical speed. To minimize any grinding or dispersion issues, we aim for the cascading action discussed prior. The most desirable angle to accomplish this falls between 50 to 60° from horizontal. The lower end of this range applies to wet grinding applications for soft materials.

Oct 19, 2006 · What it is the optimun speed for a ball mill ? - posted in Pyrotechnics: I have done a ball mill, recenly finished, but the motor has too rpms, is too fast for use in a ball mill (the pvc cylinder that i use, left of the shafts). With the motor i will use a 40 mm pulley, because i have a 50 mm driven pulley, in one of my two shafts. In the other side of my shafts there are two 40 mm .

grinding mill critical speed. Grinding Mill Critical Speed Calculation. Ball Mill Critical Speed Mineral Processing & Metallurgy. The critical speed of a rotating mill is the RPM at which a grinding medium will begin to "centrifuge", namely will start rotating with the mill and therefore cease to .

The point where the mill becomes a centrifuge is called the "Critical Speed", and ball mills usually operate at 65% to 75% of the critical speed. Ball Mills are generally used to grind material 1/4 inch and finer, down to the particle size of 20 to 75 microns.

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distributions at different grinding times, and the model parameters (S„ a-i.a.y and fy, ) were compared for five different mill speed (fractional of mill critical speed; 55%, 65%, 75%., 85% and 95%). The result of tests, the effect of fraction of mill critical speed on the grinding, it was found more different results from two different samples.

determine critical speed grinding mill . Ball Mill Critical Speed Mineral Processing & Metallurgy. The critical speed of a rotating mill is the RPM at which a grinding medium will begin to "centrifuge", namely will start rotating with the mill and therefore cease to carry out useful work.

Ball mill calculation critical speed ellulnl. ball mill calculations critical speed Grinding Mill China derivation of critical velocity of ball mill derivation of critical velocity of ball mill 23 Jan 2011, The grinding in ball mill is therefore caused due to:, charge will centrifuge is known as the critical speed of the mill and is given by formula:

How can I determine the best RPM for Dry Ball Milling .

Because you want the grinding balls to experience a free-fall motion, i.e. cataracting motion, I would recommend you consider a rotational speed between 65 and 85 % of the critical speed of the mill.

grinding mill critical speed. Grinding Mill Critical Speed Calculation. Ball Mill Critical Speed Mineral Processing & Metallurgy. The critical speed of a rotating mill is the RPM at which a grinding medium will begin to "centrifuge", namely will start rotating with the mill and therefore cease to .

PERFORMANCE ENHANCMENT TOOLS FOR GRINDING MILLS 107 The Impactmeter signals provide the information needed for mill control. By maintaining the critical impact rate in a low to nil value, the best instantaneous load movement pattern is obtained, controlled either by a human operator or the automatic control system. The main variable used for

Oct 19, 2006 · What it is the optimun speed for a ball mill ? - posted in Pyrotechnics: I have done a ball mill, recenly finished, but the motor has too rpms, is too fast for use in a ball mill (the pvc cylinder that i use, left of the shafts). With the motor i will use a 40 mm pulley, because i have a 50 mm driven pulley, in one of my two shafts. In the other side of my shafts there are two 40 mm .

Critical Speed Of Grinding Mill . Critical Speed Of Vertical Mill - mydressnaaicursus.be. Mill Critical Speed Determination The "Critical Speed" for a grinding mill is defined as the rotational speed where centrifugal forces equal gravitational forces at the mill shell's inside surface This is the rotational speed where balls will not .

critical, a variable speed drive is recommended. This permits the operator to control his mill speed to suit. Most mills rotate at 60 to 65 percent of critical speed (Nc). This formulation is for wet milling where as dry milling needs to be adjusted by 2 to 5 RPM faster. These speeds hold true for any media regardless of shape for density.

Mill Speed Control Using Programmable Logic Controllers

The paper handle a few topics from cement industry, such are: critical speed, mill speed control. If the peripheral speed of the mill is too great, it begins to act like a centrifuge and the balls do not fall back. Therefore, this application conceived a PID controller for control the mill speed, using Programmable Logic Controllers.

Figures 8.5 for the popular mill types. 3 c is the mill speed measured as a fraction of the critical speed. More reliable models for the prediction of the power drawn by ball, semi-autogenous and fully autogenous mills have been developed by Morrell and by Austin. (Morrell, S. Power draw of wet tumbling mills and its

Effect of mill speed and slurry filling on the charge .

It suggested that the average rotational kinetic energy and applied force increases with mill speed. Also the optimum grinding effect is 70% of critical speed. However, the above instrumented ball only worked in dry grinding condition and it could not be monitored data online.

The ball mill is used for grinding materials such as coal, pigments, and feldspar for pottery. Grinding can be carried out either wet or dry but the former is performed at low speed. Blending of explosives is an example of an application for rubber balls.

Model Predictive Control for SAG Milling in Minerals .

Mill rotational speed may be variable, in which case increasing speed increases grinding capacity, since this increases the rise and subsequent fall of ore and media – provided the mill is not run up to critical speed. Mill speed variation has a large gain effect in terms of control and is important to compensate for variations in ore hardness.

Dec 04, 2012 · Critical Speed Of The Ball Mill | Manganese Crusher. Search critical speed of the ball mill to find your need. . The grinding is carried out by the.the most precise . no matter what the nomenclature they all . »More detailed

STEPPING FORWARD: USING VARIABLE SPEED DRIVES FOR .

STEPPING FORWARD: USING VARIABLE SPEED DRIVES FOR OPTIMIZING THE GRINDING PROCESS IN SAG AND BALL MILLS *I. Atutxa and I. Legarra . Ingeteam Power Technology . . speed of the mill, ф, as a fraction of the critical speed (King, 2001). Q = Q m + Q t (1) Q m = 6100·J pm

Better efficiency, starts with better grinding. You've already gone through the work to bring the ore to the mill, now it's time to recover as much precious metal as possible. GrindingExpert™ automatically adjust feed rate, mill speed and water addition to reduce upsets, eliminate grind-outs and increase tonnage in SAG / ball mills. We .

tools Home - Calculations - Articles . Calculations. Millspeed Sliderule Pipe Launder Liner Height Mill filling. Calculations. Mill Critical Speed Calculation: Estimates the critical speed of a grinding mill of a given diameter given the mill inside diameter and liner thickness. If given a measured mill rotation (RPM), then the mill`s fraction .

Ball Mill Critical Speed - Mineral Processing & Metallurgy

The critical speed of a rotating mill is the RPM at which a grinding medium will begin to "centrifuge", namely will start rotating with the mill and therefore cease to carry out useful work. Ball mills have been successfully run at speeds between 60 and 90 percent of critical speed, but most mills operate at speeds between 65 and 79 percent .

(PDF) Milling curves as a tool for characterising SAG mill .

Milling curves as a tool for characterising SAG mill performance . Dropping the mill speed from 75% critical to . . The economic cost function of the grinding mill circuit is defined with .

The grinding media are usually made of high-chromium steel. The smaller grades are occasionally cylindrical ("pebs") rather than spherical. There exists a speed of rotation (the "critical speed") at which the contents of the mill would simply ride over the roof of the mill due to centrifugal action.

A comparative study on a newly designed ball mill and the .

For each critical speed, the mill was operated for 20 min. For the first 10 min of each critical speed, the mill was allowed to stabilise. During the stabilisation of the mill, the classifier section outlet valve of chamber one was kept open in order to remove the product discharged from the mill during the initial 10 min of grinding.

Jan 07, 2015 · Raw mills usually operate at 72-74% critical speed and cement mills at 74-76%. 3.2 Calculation of the Critical Mill Speed: G: weight of a grinding ball in kg. w: Angular velocity of the mill tube in radial/second. w = 2*3.14*(n/60) Di: inside mill diameter in meter (effective mill diameter). n: Revolution per minute in rpm. 7.

Mill Critical Speed Determination. The "Critical Speed" for a grinding mill is defined as the rotational speed where centrifugal forces equal gravitational forces at the mill shell's inside surface. This is the rotational speed where balls will not fall away from the mill's shell.

How can I determine the best RPM for Dry Ball Milling .

Because you want the grinding balls to experience a free-fall motion, i.e. cataracting motion, I would recommend you consider a rotational speed between 65 and 85 % of the critical speed of the mill.

SAGMILLING .:. Mill Critical Speed Determination. The "Critical Speed" for a grinding mill is defined as the rotational speed where centrifugal forces equal gravitational forces at the mill shell's inside surface. Get Price

Model Predictive Control for SAG Milling in Minerals .

Mill rotational speed may be variable, in which case increasing speed increases grinding capacity, since this increases the rise and subsequent fall of ore and media – provided the mill is not run up to critical speed. Mill speed variation has a large gain effect in terms of control and is important to compensate for variations in ore hardness.

Ball mill calculation critical speed ellulnl. ball mill calculations critical speed Grinding Mill China derivation of critical velocity of ball mill derivation of critical velocity of ball mill 23 Jan 2011, The grinding in ball mill is therefore caused due to:, charge will centrifuge is known as the critical speed of the mill and is given by formula:

Mar 20, 2017 · MATHEMATICS OF GRINDING Critical Speed:-The "Critical Speed" for a grinding mill is defined as the rotational speed where centrifugal forces equal gravitational forces at the mill shell's inside surface.This is the rotational speed where balls will not fall away from the mill's shell. Mills are driven, in practice, at speeds of 50-90% of critical speed, the choice being influenced by economic .

tools Home - Calculations - Articles . Calculations. Millspeed Sliderule Pipe Launder Liner Height Mill filling. Calculations. Mill Critical Speed Calculation: Estimates the critical speed of a grinding mill of a given diameter given the mill inside diameter and liner thickness. If given a measured mill rotation (RPM), then the mill`s fraction .

derivation of critical speed in a ball mill pdf - YouTube

May 24, 2018 · The grinding works on the principle of critical speed. Critical speed can be understood as that speed after which the steel balls (which are responsible for the grinding of DESIGN AND FABRICATION .

Effect of mill speed and slurry filling on the charge .

It suggested that the average rotational kinetic energy and applied force increases with mill speed. Also the optimum grinding effect is 70% of critical speed. However, the above instrumented ball only worked in dry grinding condition and it could not be monitored data online.

At this time, the steel ball has no impact and the grinding effect is small, so that the grinding action is stopped. When the outer ball in the Feldspar Mill rotates with the cylinder without falling, the rotational speed of the Feldspar Mill is called the critical speed. The critical speed of various Feldspar Mills is proportional to the .

Figures 8.5 for the popular mill types. 3 c is the mill speed measured as a fraction of the critical speed. More reliable models for the prediction of the power drawn by ball, semi-autogenous and fully autogenous mills have been developed by Morrell and by Austin.

## Grinding Mill Critical Speed

## What Is Critical Speed In Grinding

Grinding mill critical speed grinding mill critical speed calculation ball mill critical speed mineral processing metallurgy the critical speed of a rotating mill is the rpm at which a grinding medium will begin to "centrifuge", namely will start rotating with the mill and therefore cease to carry out useful work.

Get Price And Support Online »## Principles of Grinding in Ball Mills | Orbis Machinery, LLC.

Oct 26, 2018 · Faster RPM are required for smaller mills to reach critical speed. To minimize any grinding or dispersion issues, we aim for the cascading action discussed prior. The most desirable angle to accomplish this falls between 50 to 60° from horizontal. The lower end of this range applies to wet grinding applications for soft materials.

Get Price And Support Online »## What it is the optimun speed for a ball mill .

Oct 19, 2006 · What it is the optimun speed for a ball mill ? - posted in Pyrotechnics: I have done a ball mill, recenly finished, but the motor has too rpms, is too fast for use in a ball mill (the pvc cylinder that i use, left of the shafts). With the motor i will use a 40 mm pulley, because i have a 50 mm driven pulley, in one of my two shafts. In the other side of my shafts there are two 40 mm .

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grinding mill critical speed. Grinding Mill Critical Speed Calculation. Ball Mill Critical Speed Mineral Processing & Metallurgy. The critical speed of a rotating mill is the RPM at which a grinding medium will begin to "centrifuge", namely will start rotating with the mill and therefore cease to .

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The point where the mill becomes a centrifuge is called the "Critical Speed", and ball mills usually operate at 65% to 75% of the critical speed. Ball Mills are generally used to grind material 1/4 inch and finer, down to the particle size of 20 to 75 microns.

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distributions at different grinding times, and the model parameters (S„ a-i.a.y and fy, ) were compared for five different mill speed (fractional of mill critical speed; 55%, 65%, 75%., 85% and 95%). The result of tests, the effect of fraction of mill critical speed on the grinding, it was found more different results from two different samples.

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determine critical speed grinding mill . Ball Mill Critical Speed Mineral Processing & Metallurgy. The critical speed of a rotating mill is the RPM at which a grinding medium will begin to "centrifuge", namely will start rotating with the mill and therefore cease to carry out useful work.

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Ball mill calculation critical speed ellulnl. ball mill calculations critical speed Grinding Mill China derivation of critical velocity of ball mill derivation of critical velocity of ball mill 23 Jan 2011, The grinding in ball mill is therefore caused due to:, charge will centrifuge is known as the critical speed of the mill and is given by formula:

Get Price And Support Online »## How can I determine the best RPM for Dry Ball Milling .

Because you want the grinding balls to experience a free-fall motion, i.e. cataracting motion, I would recommend you consider a rotational speed between 65 and 85 % of the critical speed of the mill.

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grinding mill critical speed. Grinding Mill Critical Speed Calculation. Ball Mill Critical Speed Mineral Processing & Metallurgy. The critical speed of a rotating mill is the RPM at which a grinding medium will begin to "centrifuge", namely will start rotating with the mill and therefore cease to .

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PERFORMANCE ENHANCMENT TOOLS FOR GRINDING MILLS 107 The Impactmeter signals provide the information needed for mill control. By maintaining the critical impact rate in a low to nil value, the best instantaneous load movement pattern is obtained, controlled either by a human operator or the automatic control system. The main variable used for

Get Price And Support Online »## What it is the optimun speed for a ball mill .

Oct 19, 2006 · What it is the optimun speed for a ball mill ? - posted in Pyrotechnics: I have done a ball mill, recenly finished, but the motor has too rpms, is too fast for use in a ball mill (the pvc cylinder that i use, left of the shafts). With the motor i will use a 40 mm pulley, because i have a 50 mm driven pulley, in one of my two shafts. In the other side of my shafts there are two 40 mm .

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Critical Speed Of Grinding Mill . Critical Speed Of Vertical Mill - mydressnaaicursus.be. Mill Critical Speed Determination The "Critical Speed" for a grinding mill is defined as the rotational speed where centrifugal forces equal gravitational forces at the mill shell's inside surface This is the rotational speed where balls will not .

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critical, a variable speed drive is recommended. This permits the operator to control his mill speed to suit. Most mills rotate at 60 to 65 percent of critical speed (Nc). This formulation is for wet milling where as dry milling needs to be adjusted by 2 to 5 RPM faster. These speeds hold true for any media regardless of shape for density.

Get Price And Support Online »## Mill Speed Control Using Programmable Logic Controllers

The paper handle a few topics from cement industry, such are: critical speed, mill speed control. If the peripheral speed of the mill is too great, it begins to act like a centrifuge and the balls do not fall back. Therefore, this application conceived a PID controller for control the mill speed, using Programmable Logic Controllers.

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Figures 8.5 for the popular mill types. 3 c is the mill speed measured as a fraction of the critical speed. More reliable models for the prediction of the power drawn by ball, semi-autogenous and fully autogenous mills have been developed by Morrell and by Austin. (Morrell, S. Power draw of wet tumbling mills and its

Get Price And Support Online »## Effect of mill speed and slurry filling on the charge .

It suggested that the average rotational kinetic energy and applied force increases with mill speed. Also the optimum grinding effect is 70% of critical speed. However, the above instrumented ball only worked in dry grinding condition and it could not be monitored data online.

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The ball mill is used for grinding materials such as coal, pigments, and feldspar for pottery. Grinding can be carried out either wet or dry but the former is performed at low speed. Blending of explosives is an example of an application for rubber balls.

Get Price And Support Online »## Model Predictive Control for SAG Milling in Minerals .

Mill rotational speed may be variable, in which case increasing speed increases grinding capacity, since this increases the rise and subsequent fall of ore and media – provided the mill is not run up to critical speed. Mill speed variation has a large gain effect in terms of control and is important to compensate for variations in ore hardness.

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Dec 04, 2012 · Critical Speed Of The Ball Mill | Manganese Crusher. Search critical speed of the ball mill to find your need. . The grinding is carried out by the.the most precise . no matter what the nomenclature they all . »More detailed

Get Price And Support Online »## STEPPING FORWARD: USING VARIABLE SPEED DRIVES FOR .

STEPPING FORWARD: USING VARIABLE SPEED DRIVES FOR OPTIMIZING THE GRINDING PROCESS IN SAG AND BALL MILLS *I. Atutxa and I. Legarra . Ingeteam Power Technology . . speed of the mill, ф, as a fraction of the critical speed (King, 2001). Q = Q m + Q t (1) Q m = 6100·J pm

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Better efficiency, starts with better grinding. You've already gone through the work to bring the ore to the mill, now it's time to recover as much precious metal as possible. GrindingExpert™ automatically adjust feed rate, mill speed and water addition to reduce upsets, eliminate grind-outs and increase tonnage in SAG / ball mills. We .

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tools Home - Calculations - Articles . Calculations. Millspeed Sliderule Pipe Launder Liner Height Mill filling. Calculations. Mill Critical Speed Calculation: Estimates the critical speed of a grinding mill of a given diameter given the mill inside diameter and liner thickness. If given a measured mill rotation (RPM), then the mill`s fraction .

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The critical speed of a rotating mill is the RPM at which a grinding medium will begin to "centrifuge", namely will start rotating with the mill and therefore cease to carry out useful work. Ball mills have been successfully run at speeds between 60 and 90 percent of critical speed, but most mills operate at speeds between 65 and 79 percent .

Get Price And Support Online »## (PDF) Milling curves as a tool for characterising SAG mill .

Milling curves as a tool for characterising SAG mill performance . Dropping the mill speed from 75% critical to . . The economic cost function of the grinding mill circuit is defined with .

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The grinding media are usually made of high-chromium steel. The smaller grades are occasionally cylindrical ("pebs") rather than spherical. There exists a speed of rotation (the "critical speed") at which the contents of the mill would simply ride over the roof of the mill due to centrifugal action.

Get Price And Support Online »## A comparative study on a newly designed ball mill and the .

For each critical speed, the mill was operated for 20 min. For the first 10 min of each critical speed, the mill was allowed to stabilise. During the stabilisation of the mill, the classifier section outlet valve of chamber one was kept open in order to remove the product discharged from the mill during the initial 10 min of grinding.

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Jan 07, 2015 · Raw mills usually operate at 72-74% critical speed and cement mills at 74-76%. 3.2 Calculation of the Critical Mill Speed: G: weight of a grinding ball in kg. w: Angular velocity of the mill tube in radial/second. w = 2*3.14*(n/60) Di: inside mill diameter in meter (effective mill diameter). n: Revolution per minute in rpm. 7.

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Mill Critical Speed Determination. The "Critical Speed" for a grinding mill is defined as the rotational speed where centrifugal forces equal gravitational forces at the mill shell's inside surface. This is the rotational speed where balls will not fall away from the mill's shell.

Get Price And Support Online »## How can I determine the best RPM for Dry Ball Milling .

Because you want the grinding balls to experience a free-fall motion, i.e. cataracting motion, I would recommend you consider a rotational speed between 65 and 85 % of the critical speed of the mill.

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SAGMILLING .:. Mill Critical Speed Determination. The "Critical Speed" for a grinding mill is defined as the rotational speed where centrifugal forces equal gravitational forces at the mill shell's inside surface. Get Price

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Mill rotational speed may be variable, in which case increasing speed increases grinding capacity, since this increases the rise and subsequent fall of ore and media – provided the mill is not run up to critical speed. Mill speed variation has a large gain effect in terms of control and is important to compensate for variations in ore hardness.

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Ball mill calculation critical speed ellulnl. ball mill calculations critical speed Grinding Mill China derivation of critical velocity of ball mill derivation of critical velocity of ball mill 23 Jan 2011, The grinding in ball mill is therefore caused due to:, charge will centrifuge is known as the critical speed of the mill and is given by formula:

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Mar 20, 2017 · MATHEMATICS OF GRINDING Critical Speed:-The "Critical Speed" for a grinding mill is defined as the rotational speed where centrifugal forces equal gravitational forces at the mill shell's inside surface.This is the rotational speed where balls will not fall away from the mill's shell. Mills are driven, in practice, at speeds of 50-90% of critical speed, the choice being influenced by economic .

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tools Home - Calculations - Articles . Calculations. Millspeed Sliderule Pipe Launder Liner Height Mill filling. Calculations. Mill Critical Speed Calculation: Estimates the critical speed of a grinding mill of a given diameter given the mill inside diameter and liner thickness. If given a measured mill rotation (RPM), then the mill`s fraction .

Get Price And Support Online »## derivation of critical speed in a ball mill pdf - YouTube

May 24, 2018 · The grinding works on the principle of critical speed. Critical speed can be understood as that speed after which the steel balls (which are responsible for the grinding of DESIGN AND FABRICATION .

Get Price And Support Online »## Effect of mill speed and slurry filling on the charge .

It suggested that the average rotational kinetic energy and applied force increases with mill speed. Also the optimum grinding effect is 70% of critical speed. However, the above instrumented ball only worked in dry grinding condition and it could not be monitored data online.

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At this time, the steel ball has no impact and the grinding effect is small, so that the grinding action is stopped. When the outer ball in the Feldspar Mill rotates with the cylinder without falling, the rotational speed of the Feldspar Mill is called the critical speed. The critical speed of various Feldspar Mills is proportional to the .

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Figures 8.5 for the popular mill types. 3 c is the mill speed measured as a fraction of the critical speed. More reliable models for the prediction of the power drawn by ball, semi-autogenous and fully autogenous mills have been developed by Morrell and by Austin.

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