MP - Liners

Crusher Liners Presentation

The Mantle and Bowl Liner

BOWL LINER

Backing Material

Standard Backing

Standard backing is a general purpose backing material used in Cone Crushers under normal operating conditions. This backing material has a compressive strength of 16,000 PSI and a cure time of 6 hours at 70°F.

HP Backing

HP backing is an intermediate strength backing material used in Cone Crushers such as the HP200 to HP500 and all Omnicones operating in tougher applications. This backing

material has a compressive strength of 16,500 PSI and a cure time of 5 hours at 70°F.

WF Backing

WF backing is an ultra performance backing material used in such Crushers as the MP800 & MP1000 in highly demanding applications. This backing has a compressive strength of

18,000 PSI and a cure time of 7 hours at 70°F.

What Causes Liner Wear

 _{The abrasiveness of the rock being}

crushed is measured as an Abrasion Index number. The hardness of the rock being crushed is measured as a Work Index number.

 _{The abrasiveness of the rock is what} wears the liner material away.

 _{The hardness of the rock dictates how} much rock you can crush with a given amount of horsepower.

The characteristics of the material being crushed, abrasiveness and

hardness, determines how long liners will last.

Abrasiveness and Hardness

 Canadian Kimberlite (NWT)

 Ohio Limestone

 Wisconsin Limestone

Non-Abrasive Material

Abrasion Index Work Index

Non-Abrasive Material

Abrasion Index Work Index

Abrasive Material

Abrasive Material

Very Abrasive Material

Very Abrasive Material

0.01

0.02

0.05

5.8

13.5

14.1

 Alabama Basalt

 South Dakota Rhyolite

 Canadian Granite (ONT)

 Utah Copper Ore

0.28

0.21

0.56

0.26

10.7

6.6

17.2

11.1

 Oklahoma Granite

 Nevada Gold Ore

0.78

0.94

14.0

7.5

Crushing is Done in Stages

As no one single Crusher can reduce shot rock or large gravel to

finished product sizes, crushing must be done in stages. The table below

lists the stages of crushing in a typical crushing plant.

Stage Type of Crus he r Approxim ate Setting

Primary - 1st Jaw or Gyratory 4" (100mm) to 8" (200mm) Secondary - 2nd Standard Cone or HSI 1-1/2" (38mm)

Tertiary - 3rd Short Head Cone or HSI 3/8" (10mm)

Standard & Shorthead Crushers

 _{Applied in the second (secondary)} stage

 _{Normally produces products over 1"} (25mm)

 _{6 to 8:1 maximum ratio of reduction}  _{Usually operated in open circuit}  _{Normally is not choke fed}

 _{Normally prepares the material for} the next stage of crushing

 _{Applied in the third (tertiary) stage}  _{Normally produces products under 1"}

(25mm)

 _{4 to 6:1 maximum ratio of reduction}  _{Usually operated in closed circuit}  _{Operated choke fed for best results}  _{Normally produces the desired}

products

Standard Liner Example

 _{The liner shown to the left} illustrates the difference between the open side feed opening dimension and the closed side feed opening dimension of an MP1000 Standard coarse liner.

Shorthead Liner Example

 _{The liner shown to the left}

illustrates the difference between the open side feed opening

dimension and the closed side feed opening dimension of an MP1000 Short Head coarse liner.

Converting Liner Configuration

 _{All MP Crushers can be converted} from a standard crusher

configuration to a short head

crusher configuration or vice versa at anytime.

 _{The only item that changes is the} liners.

 _{The quantity of backing material} required will also change.

Open & Closed Crushing Circuits

Crusher Setting Suggestion

To optimize production, the correct cone Crusher closed side

setting must be maintained. As a "rule of thumb" a cone

Crusher operating in closed circuit should be set at:

1/8” (3mm) larger than or equal to the cloth size the system is closed on

Note: The setting of a Crusher operating in open circuit is based on the wanted top size of that product.

Product Size vs. Setting

Approximately 80% (*) of the material coming out of an MP cone

Crusher will be passing it’s closed side setting dimension.

CRUSHER SETTING VS. PRODUCT SIZE

MP Crushers

Setting Compared to Power Draw

Closed Side Setting

H

o

rs

ep

ow

er

/

T

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n

 _{A small change in setting} results in a large change in power draw.

 _{There will always be a} direct relationship of quantity of material

produced in comparison to power being used.

Maximum Feed Size

100% of the Crusher feed material should be equal to or smaller than

the liners closed side feed opening dimension

Maximum Feed Size

 _{Closed side feed opening is 5.09",} maximum feed size for an MP Crusher would be 5.09"

Open Side Feed Opening - 6.91” Closed Side Feed Opening - 5.09”

Concerned About Throughput

If at some point in time, your concerned about the quantity of material

passing through your cone Crusher, you can make a capacity check to

determine actual Crusher throughput and compare it to the capacity chart

in the instruction manual.

 _{S = belt Speed (FPM)}

 _{W = Weight of 1 foot of material}

 _{60 = 60 minutes in one hour}

 _{2000 = 2000 pounds per short ton}

S x W x 60

Commit to A Liner Study

The following three exercises can be completed in the field

by anyone who is concerned about the liners that are being

used. This “liner study” is used to determine if the liners

being used are correct for the application.

1) Create a Liner Wear Profile

2) Calculate the Amount of Liner Utilization

3) Determine the Crusher’s Ratio of Reduction

Create a Liner Wear Profile

 _{Cut through a mantle / bowl liner from top to} bottom vertically

 _{Trace the wear profile on paper or cardboard}  _{Send wear profile to Metso Minerals}

 _{We scan the worn profile}

 _{We will compare the worn profile to a new} profile via computer image overlapping

Determine Liner Utilization

 _{Weigh the worn mantle and} bowl liner

 _{Weigh the new mantle and} new bowl liner

 _{Calculate the amount of liner} utilization

Note: As a rule of thumb, the amount of weight in percentage that you can expect to utilize if the application is correct is 50%

Determine the Ratio of Reduction

 _{Take samples of the feed and product}  _{Run sieve analysis on samples}

 _{Determine sizes for 80% of feed and product}  _{Divide F80 by P80}

 _{The result is the Ratio of Reduction}

Calculate the Ratio of Reduction that’s taking

place in your Crusher by:

Calculate the Ratio of Reduction

Material samples are taken of the feed entering the Crusher and discharging out of

the Crusher. Sieve analysis is completed on both samples.

Size Cum ulative % Passing 5" (127mm) 100% 3" (76mm) 55% 1-3/4" (44mm) 28% 1-1/2" (38mm) 22% 7/8" (22mm) 4%

Size Cum ulative % Passing 1-1/2" (38mm) 100% 7/8" (22mm) 97% 3/4" (19mm) 76% 1/2" (13mm) 43% 3/8" (10mm) 29% 4M (4.75mm) 13% 8M (2.36mm) 7%

FEED

PRODUCT

Use The Proper Liners

 _{Feed size to the Crusher determines the style of liners to be used (top size feed must} fit in crushing cavity)

 _{The Ratio of Reduction should not exceed 4 to 6:1 in a short head or 6 to 8:1 in a} standard (Crusher must not be operated below it's minimum setting)

Use the correct liners to make your products...

Note: A gradual decrease in product being produced usually means that the liners are worn out (liner feed opening closes off as liners wear away)

Keep in Mind…..

To operate continuously with liners unsuited for the

operation will result in:

 _{Uneconomical wear of the liners (poor liner wear profile)}  _{Inefficient crushing (poor ratio of reduction)}

Product Quality Keys

To maximize product quality and uniformity, the

following points must remain consistent:

 _{Keep the Crusher feed gradation consistent by maintaining consistent Crusher} settings (all Crusher settings)

 _{Maintain consistent feed distribution (center feeding a must)}  _{Eliminate feed segregation}

 _{Run at a consistent cavity level (12” above the feed plate)}  _{Operate at a consistent power draw}

Incorrect Liner Example

 _{Feed material percolates around} the feed opening

 _{Production decreases as the feed} opening is bridged over

 _{Volume limit is exceeded at} minimal power draw

If Feed Size is too Large

Incorrect Liner Example

 _{Majority of crushing takes place in the} lowest portion of the cavity

 _{Production decreases due to a poor} ratio of reduction

 _{Power and/or force limit of the} Crusher is exceeded at a minimal volume level

 _{Risk of improper bearing alignment}

If Feed Size is too Small

Capacity Dropping Off

Typical reasons that capacity begins to drop off:

 _{Feed opening has closed off}  _{Extremely slabby feed}

 _{Incorrect feed distribution}

 _{Feed contains a high amount of debris}  _{Tilted adjustment ring}

Long and Short Liners

 _{Usually, long liners will allow the Crusher to do more work than short liners (draw} more power).

 _{The extra work will usually show up in the generation of a finer product, rather than} higher production.

 _{Long liners may help generate a more cubical shaped product.}

Use Matched Liners!

 _{Make certain you are using matched liners}

 _{Use the correct mantle with the correct bowl liner}  _{Use a long mantle with a long bowl liner}

 _{Use a short mantle with a short bowl liner}  _{Use a new mantle with a new bowl liner}

Mixing and matching liners by accident or on purpose usually does

not work. Liners are designed to be used as a matched set. Using a

matched set of liners assures that the nip angle between the mantle

and bowl liner is correct thus giving optimum performance.

Tips to Extend Liner Life

 _{Operate 50% rated power (65% amps) with a full cavity for 6 hours.}  _{Operate 75% rated power (80% amps) with a full cavity for 2 hours.}  _{Operate at or near 100% rated power (100% amps) from this point on.}

 _{The Crusher normally operates near full power draw}

 _{Increasing the Crusher setting in order to operate at the lighter power levels does not} effect the crushing circuit.

Note: Metso Minerals has found that when customers have followed this procedure, they have seen as high as 30% increases in liner life.

Follow these steps after new liners are installed:

 _{The MP head rotates quickly clockwise while operating no load.}

 _{When feed enters the crushing cavity, it rubs against the fast moving mantle and if done} frequently throughout the day (switching from load to no load), it may prevent the liners from work hardening properly.

 _{Liners will work harden and get tougher if you can maintain a steady feed rate to the} crusher all day long.

Tips to Extend Liner Life

 _{Many times water is used above the Crusher to control dust.}

 _{Too much water can cause fines to be washed down the face of the mantle which can cause} premature liner wear.

Limit the quantity of water used to control dust!

* Keep a material load on the Crusher all day!

Note: * The MP800 is available with an Anti-Spin system that prevents the head from turning during no-load operation.

Storing Liners

 _{Store liners right side up to prevent distortion of the liner (egg shaping) and keep them in} matched sets to prevent confusion at liner change time.

Considering Thick Liners?

 _{There must be a minimum of 1½ bowl threads} engaged into the adjustment ring threads in order to keep the bowl tight while crushing. The potential problem when using thick liners is a lack of thread engagement. This can lead to thread damage and very costly repairs.

 _{Thick liners increase the feed opening nip angle.} This can lead to percolating of the feed

material, not allowing the material to flow properly through the crushing cavity.

 _{The additional weight of thick liners can also} lead to a Crusher balance problem.

Must be

proper

When To Change Liners

 _{A thinning mantle and thinning bowl liner will flex.}  _{Flexing liners will crack out the backing material.}

 _{Continued flexing will “powder out” the backing material.}  _{The flexing deteriorates the head and bowl seating surfaces.}

 _{The seating surfaces eventually will need reconditioning as liners will no} longer stay tight.

Liners pushed too long can and will lead to

mechanical problems with the Crusher

Note: Liners need to be changed well before they are cracked, broken, loose, or have holes in them!

When to Change Liners

Some customers measure the

distance between the

underside of the adjustment

cap and the top of the

adjustment ring. This creates

a reference point for the next

liner change.

Change the liners at the same

time each time by watching

the adjustment cap height

Adjustment Cap

Adjustment Ring

When To Change Liners

Some customers watch and

record the total number of

crushing hours on a set of

liners. Once established, this

creates a bench mark for the

next set of liners.

Change the liners at the same

time each time by watching

the total number of crushing

hours on the liners

00755

Crusher Hour

Meter

When To Change Liners

Some customers watch and

record the total tons of feed

material that passed through

the liners. Once established,

this creates a bench mark for

the next set of liners.

Change the liners at the same

time each time by watching the

total tons of material that passed

through the set of liners

When to Change Liners

The volumetric area of the liner

decreases late in liner life as the feed

opening closes off. This results in

lower throughput and a substantial

loss in salable product. An excellent

time to change liners is when a 10%

loss of product is noticed.

Change the liners at the same

time by watching for a reduction

in throughput caused by the

closing off of the liners feed

opening.

Excessive Liner Utilization

 _{Liners pushed too long can cause serious damage to the cone Crusher. A cracked, loose,} or flexing liner will deteriorate the head seating surface and the bowl seating surface. These surfaces will eventually need to be re-conditioned; a costly maintenance repair that drives up the cost of producing the finished product.

Tramp Iron Passage

 _{Tramp metal passage should be kept to a minimum as it can be damaging to the cone} Crusher. A metal detector and magnet can be added to the circuit in front of the Crusher