load factor for sag mill

An improved method for grinding mill filling measurement and …

If an accurate estimate of the mill contents is required, for example, to calibrate load cells, the total mill and load volumes including due to the conical ends and lifters should be calculated. Results. The new measurement technique is demonstrated by surveying the load of a large SAG mill following a crash stop and a subsequent grind-out.

SAG vs. AG Mills: Understanding the Key Differences

The type of grinding media used in each mill has a significant impact on the performance of the mill. SAG Mill Grinding Media. SAG mills use a combination of steel balls and rock particles as grinding media. The addition of rock particles to the SAG mill feed allows the mill to break larger rocks, thus increasing the grinding efficiency.

A guide to SAG Mill management

Stable mill load translates to consistent product size, a crucial factor for achieving maximum recovery in flotation. The best part? Well-designed and …

Ball Mill Circulating Load

Calculating a grinding circuit's circulating loads based on Screen Analysis of its slurries.. Compared to %Solids or Density based Circulating load equations, a more precise method of determining grinding circuit tonnages uses the screen size distributions of the pulps instead of the dilution ratios.Pulp samples collected around the ball mill or rod …

SAG Mill Grinding Circuit Design

Common convention generally refers to high-aspect ratio mills as SAG mills (with diameter to effective grinding length ratios of 3:1 to 1:1), low-aspect ratio mills …

(PDF) Real-Time Estimation of SAG Mill Charge …

The methodologies outlined all allow analysis of real-time data and large data sets spanning months and years of operation, thus facilitating identification of optimum …

Multi-component AG/SAG mill model

The JKMRC has been studying and modelling industrial AG and SAG mills for over 40 years, but the ability to simulate the effects of blending hard and soft components on mill performance remains quite limited.In an effort to quantify these effects for modelling purposes, a series of laboratory, pilot scale and full scale tests, using multi-component …

COMMINUTION

SAG mill feed, grate size, open area, classification size, ball diameter or ball charge, total mill load, mill speed, etc. can be investigated at pilot plant scale. All tests are evaluated based on: • Feed rate • Power consumption • Product size analysis Unless single-stage autogenous grinding is considered, we recommend that the

MILLING CURVES AS A TOOL FOR CHARACTERISING …

MILL FILLING AND LOAD As already discussed, SAG mill filling is a critical parameter for SAG mill performance. Yet, no percentage mill filling indications are present in

Choosing a SAG Mill to Achieve Design Performance

Provide a motor with the capability to deliver design power on a continuous basis by including a suitable service factor, usually 15% to cover any drive losses and …

SAG Mills Load Cells

Yes, you add load cells to existing SAG Mills; it depends on the type of mill bearing support system. They are normally button type compressive cells. ... Using Audio to "listen" to mill load is still in use, however more in dry grinding mills. I have installed several of these systems in wet mills; however this was used to check mill speed ...

Dynamic modelling and simulation of semi-autogenous mills

The proportion of grinding media is another factor affecting mill operation. It has undergone an important evolution lately. Originally it was considered that a SAG mill should work at 8–10% ball content. Later-on, larger mill sizes and larger processed tonnages have led to operations at 10–14% level.

Circulating Load Calculation Formula

Cytec Handbook. Why have a large circulation load:. If a product all finer than a certain critical size is required, the capacity of the ball mill is increased considerably by using it in closed circuit with a classifier and this increase is made still greater by increasing the circulating load in between the ball mill and the classifier (Fig. 70).

Design SAG mill production when you need it most: In …

Maximum power gives maximum throughput: Not so – depending on the liners. Throughput peaks at 26% load while power peaks at about 35% load. When overloaded, a SAG mill …

, Possible trajectories of steel balls in a SAG mill. Load "Toe"

A semiautogenous grinding mill (SAG) uses complementary steel balls of typical 5-inch diameter to support the grinding media. Fig. 2 shows the possible tra- jectories inside the mill.

Toe angle measurement for SAG mill control at Lihir gold …

SAG Mill process control classically maintains the SAG mill volumetric filling within a set operating range. Typically a SAG mill weight measurement, by either bearing pressure transducers or load cells, is used as an inferred measurement of volumetric filling. To maintain volumetric filling within a set operating range the SAG weight setpoint use for …

Gearless mill drives

• 28 MW GMD for a 40' SAG mill • 28 MW GMD for 42' SAG mill Whether it is size or an installation at the highest altitude (4600 m.a.s.l.), ABB's GMDs are well positioned to contribute to the building of larger and ever more powerful mills. — Leading the gearless mill drive evolution The ABB gearless mill drive (GMD) is the most powerful ...

(PDF) Real-Time Estimation of SAG Mill Charge …

draw versu s SAG mill load for the Cadia SAG mill (Hart et al., 2001). Both show how the t hroughput and mil l- ... and other factors of the mill charge which are unique to ea ch mill .

SAG Mill Optimization using Model Predictive Control

Model predictive control is able to optimize the control of processes that exhibit an integrating type response in combination with transport delays or variable interaction, …

Unlock SAG mill capacity with process control optimisation

The instrumentation installed on a SAG mill is integral to control. For example, the mill load and noise sensors are instruments that provide essential information for an optimized SAG mill operation. Insufficient understanding of the ore characteristics and feed composition can result in an ineffective SAG mill operation.

Advanced Simulation for Semi-Autogenous Mill …

The model output variables are: power-draw, load level, ball load, mineral discharge rate and size distribution, water discharge rate, ball throughput, bearing pressure, pebble throughput, and toe and shoulder angles of the internal load. 2.1 SAG mill model The particles fed to the mill are ground in the milling chamber and subsequently

AG – Autogenous & SAG Semi-Autogenous Mill Design …

When the normal operating horsepower has been defined. It can be related to a design drive horsepower. If the mill operating horsepower is defined as "net at the shell", then the appropriate losses for trunnion bearings, pinionshaft bearings, and gearing must be accounted for to compute …

Optimization of the SAG Grinding Process Using Statistical …

2. Background. The SAG grinding process has been modeled by various authors, either generating explanatory models of the grinding process, with the aim of modeling, simulating, and optimizing the individual process, as well as integrating it into aggregate processes, such as the mine-to-mill (M2M) paradigm, a practice that has …

Closed circuit ball mill – Basics revisited

Highlights Circulating load and classification efficiency effect on ball mill capacity revisited. Relative capacity model introduced and validated. Relationship between circulating load and classification efficiency verified by industrial data. Existing fine screening technology could increase ball mill circuit capacity 15–25%.

Developments in the understanding of South African style SAG …

One such example by the authors is the study on varying the mill filling, and how this contributed to modifying the load relationship in the JKMRC SAG mill model, Powell et al. (2001). ...

Effect of Mill Volumetric Load Level % Solids & Speed on SAG Mill …

The second major factor which has impeded the development of more advanced and effective SAG mill control procedures is the lack of available instrumentation to measure important SAG mill process variables. For example, the volumetric load level within a SAG mill is perhaps the single most important factor which characterizes the …

Real-Time Estimation of SAG Mill Charge Characteristics …

Semi-autogenous grinding (SAG) mill key performance indicators (KPI), such as throughput, specific-energy consumption, and product size, are sensitive to the total …

AN UPDATED DATA SET FOR SAG MILL POWER MODEL …

SAG mill power draw models are used in mill design and grinding circuit modelling to predict how much power will be consumed by a particular mill geometry and operating …

What's the Difference Between SAG Mill and Ball Mill

Difference Between SAG Mill and Ball Mill, from the working principle, application, structure, etc. Grind and blend solid or hard materials into smaller pieces by means of shear, impact and compression. ... The pressure indication of the high pressure oil circuit can be used to reflect the load of the mill indirectly. When the mill stops ...