Sandvik H6800 Dust Seal Figure 1

Sandvik H6800 Dust Seal Improvement

One of our customer import two sets of  Sandvik H6800 cone crushers in the 2015 year. After using the new cone crusher, the crushing efficiency has been greatly improved and the production capacity has been further improved. However, there are still some problems need to solve. Such as the dust seal problem: After several years of use, it was found that the dust seal of the H6800 single-cylinder hydraulic cone crusher wears faster and consumes more. Each crusher needs to replace about 4 dust seals per year, worth about 140,000 yuan, and the equipment has high operating costs.

Cause Analysis

The dust seal is supported under the moving cone, and the dust cover can move and slide freely, as shown in Figure 1.

Sandvik H6800 Dust Seal Figure 1

  • 1.Dust seal     2.Gear ring     3.Support ring    4.Rubber scraper     5.Dust cover

Due to the relative movement between the dust seal and the dust cover, the wear is faster. After about 3 to 4 months, the gap between the dust seal and the dust cover exceeds the allowable clearance and must be replaced.

Improvement

Aiming at the problem of large wear of the dust seal, a comprehensive analysis was carried out, and corresponding transformation and utilization were carried out.

  • To measure the dust seal that needs to be replaced with excessive wear, find a groove with a width of 8 mm and a depth of 7.8 mm on the inner working surface, see Figure 2.
  • Insert a rubber ring of φ 8.5 mm in this groove, and press and connect the joint.
  • After inserting the rubber ring, clean the burrs of the groove and press the rubber ring. Be careful not to let the rubber ring undulate when lifting.

Sandvik H6800 Dust Seal Figure 2

Notices

  • Always check for leaks during operation and replace the rubber ring regularly. The rubber ring is usually replaced periodically when the moving cone liner is replaced.
  • Pay attention to the wear of the dust ring. If the wear is large, replace the dust seal. Replace approximately one dust seal per year.

The Result

The modification of the dust seal of the Sandvik H6800 crusher can effectively prevent dust and dirt from entering the broken lubrication system, which can meet the requirements of equipment operation, and only use one dust seal per year, which can save 105,000 yuan than before the transformation.

 

 

 

Change Cone Crusher Liner

When And How To Change Cone Crusher Liner?

When Need To Change Cone Crusher Liner?

Cone crusher liner needs to be changed well before they are cracked, broken, loose, or have holes in them! If cone crusher liner pushed too long can and will lead to mechanical many problems with the Crusher:

  • 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.

In our experience that too many people lean towards too late, the optimum time to change a liner really depends on how much money you are prepared to lose to production losses to get the maximum use out of a wear component.

The first condition that is optimum is that the liner change happens when you planned it. This gives you the opportunity to have all of the required parts on-hand before starting. This also allows you to perform other maintenance work on other equipment when the change is being conducted. These days it’s tough to get screen media and manganese on a moment’s notice and you will need to plan things if you need to rent a crane.

The second condition is changing the liner before you start to suffer significant production losses. On top adjust/screw adjust cones this is especially true as the feed size starts to shrink pretty dramatically as soon as you get to the last 1/3 of life and as you near the end the feed size can get very small, losing as much 30% of feed size. This is less of an issue with hydrocodones as the feed size remains constant throughout the life of the manganese.

You should have a pretty good idea when you will need to change manganese and be able to have all of the parts on hand prior to needing to change. By having an accurate belt scale, you can know to the day when your production starts to tail off to the threshold and schedule the change immediately.

What is the threshold for a liner change? We believe the maximum threshold for a liner change is as follows: Change your liners no later than a 10% decline in production.

Also, there are some other notices:

  • Change the cone crusher liner sat the same time each time by watching the adjustment cap height. 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. Such as Nordberg GP series cone crusher, When the dimension is 10mm-15mm, the GP cone crusher liner needs change.
  • Change the cone crusher liner at the same time each time by watching the total number of crushing hours on the liners. Some customers watch and record the total number of crushing hours on a set of liners. Once established, this creates a benchmark for the next set of liners. Such as Nordberg MP series cone crusher, most of the original crusher liners can work around 755 hours.
  • Change the cone crusher liner at the same time each time by watching the total tons of material that passed through the set of liners. Some customers watch and record the total tons of feed material that passed through the liners. Once established, this creates a benchmark for the next set of liners.
  • Change the cone crusher liner at the same time by watching for a reduction in throughput caused by the closing off of the liners feed opening.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.

How To Change Cone Crusher Liner?

  • On the initial set of new liners, place a mark on the adjustment cap driver ring where the pinion tooth makes contact with a driver ring tooth when the target crusher setting has been achieved.
  • Keep an accurate record of the number of teeth used to compensate for liner wear on this set of liners.
  • After the initial set of liners have worn out, but before moving the bowl, record the total number of teeth the driver ring has moved and also paint a horizontal liner on the side of the dust shell just below the bottom of the adjustment cap. This will be the baseline for determining how close the next liner sets are to being worn out.
  • When a new liner set has been installed, keep a record of the number of teeth the driver ring has moved and compared this number to the total number from the initial set of liners. This will give an estimation of the liner wear. The horizontal mark painted on the dust shell will also be indicated when the liners are approaching the wear limit. The approximate minimum heights of the adjustment cap (A-dimension) with worn liners are listed in the attached tables.

When changing liners and determining liner wear, follow the instructions in the related cone crusher instruction manual.

Extend Crusher Liner Life

Extend Crusher Liner Life Tips

There are some tips to extend crusher liner life:

1. When changing the new crusher liners, you need following these steps

  • 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 affect the crushing circuit.

2. Limit the quantity of water used to control dust!

  • 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.

3. Keep a material load on the Crusher all day!

  • 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.

4. Change New Material Crusher Liner, Such as the TIC Insert Cone Crusher Parts

When changing to TIC insert cone liner and bowl liner, the span life can be 2-3 times than normal manganese cone liner and bowl liner. Titanium carbide (TiC) cone crusher wear parts are designed to increase the wear life of wear parts in abrasive environments. Titanium carbide columns are cast within proprietary alloys for added strength and durability.

 

Nordberg MP Series Cone Wear Parts Selection Guide

Nordberg MP Series Cone Wear Parts Selection Guide

The Nordberg MP Cone crusher is a compressive crusher in which feed material is crushed between a fixed bowl liner and a moveable mantle. Bigger rock particles are crushed directly between the surfaces of the mantle and bowl liner. This is called single layer crushing. Smaller rock particles are crushed between other rock particles, which is termed multi-layer crushing or inter-particle comminution. Multi-layer crush-ing plays a significant role in the MP cavity. This improves the reduction through the crusher and end product shape.

Each MP Cone Crusher has sever-al cavity options with different feed openings and setting ranges. The correct cavity can be selected based on the feed size, setting, and application. Standard liners are typically used in secondary applications. Secondary applications don’t necessarily need to be operated in the closed circuit, but preferably choke fed. Short head liners are used in tertiary or quaternary stage applications for fine crushing and may be in closed circuit returning to the crusher. Liners are manufactured from XT510,XT515, XT520, XT525, XT710, XT750 or XT770 material depending on the application and material characteristics.

Nordberg MP Series Cavities Selection

Part Number Description Crusher Type Weight
1048315201 BOWL LINER STANDARD MEDIUM MP800 4,132.000
1048315250 BOWL LINER SHORT HEAD – FINE MP800 3,908.000
1048315255 BOWL LINER SHORT HEAD – MEDIUM MP800 4,451.000
1050143900 MANTLE STANDARD MP800 4,347.000
1050143950 MANTLE SHORT HEAD MP800 4,987.000
1050143953 MANTLE SHORT HEAD MEDIUM INTERMEDIATE MP800 4,700.000
10P1018901 BOWL LINER MODIFIED, SH HD MEDIUM MP800 4,414.000
MM0314033 BOWL LINER SHORT HEAD COARSE MP800 3,561.000
1048315559 BOWL LINER STANDARD MP1250 6234
MM0366360 MANTLE STANDARD MP1250 5383

Cone Crusher Mantle And Concave Ring Material Selection

The standard cone crusher mantle and concave ring material is manganese, but depending on the feed characteristics a variety of other alloys can be chosen to achieve the best cost per produced ton. The upper concave tiers must withstand high impact forces. The lower tiers require maximum abrasion resistance. There are some kinds of material selection:

1. High Manganese Steel

Manganese is essential to iron and steel production by virtue of its sulfur-fixing, deoxidizing, and alloying properties, as first recognized by the British metallurgist Robert Forester Mushet (1811–1891) who, in 1856, introduced the element, in the form of Spiegeleisen, into steel for the specific purpose of removing excess dissolved oxygen, sulfur, and phosphorus in order to improve its malleability. Steelmaking, including its ironmaking component, has accounted for most manganese demand, presently in the range of 85% to 90% of the total demand.  Manganese is a key component of low-cost stainless steel. Often ferromanganese (usually about 80% manganese) is the intermediate in modern processes.

Small amounts of manganese improve the workability of steel at high temperatures by forming a high-melting sulfide and preventing the formation of a liquid iron sulfide at the grain boundaries. If the manganese content reaches 4%, the embrittlement of the steel becomes a dominant feature. The embrittlement decreases at higher manganese concentrations and reaches an acceptable level at 8%. Steel containing 8 to 15% of manganese has a high tensile strength of up to 863 MPa.Steel with 12% manganese was discovered in 1882 by Robert Hadfield and is still known as Hadfield steel (Mangalloy). It was used for British military steel helmets and later by the U.S. military.

The Type of High Manganese Steel For Concave and Mantle

  • Mn14Cr2
  • Mn18Cr2
  • Mn22Cr2

2.TIC Insert Manganese Steel

Titanium Carbide (TiC) cone crusher wear parts are designed to increase the wear life of wear parts in abrasive environments. Titanium carbide columns are cast within proprietary alloys for added strength and durability.

Under this material, Concave and mantle working life can be 2-3 times than normal high manganese steel parts. Especially, when crushing hard stone, its span life can be more time.

3.High Mn Steel Matrix Ceramic Composite

High Mn Steel matrix ceramic composite concave and mantle had tested in many customers who use cone crusher to crush hard stone, its span life also better than normal manganese steel.

 

In fact, there are many kinds of material for cone crusher concave and mantle, which material is the best? Its based on the cost performance and real quality inquiry.

 

Top 5 Largest Cone Crusher Parts Manufacturer In China

The writer has focused on export crusher wear parts more than 10 years. Based on my experience, now I list the “Top 5 Largest Cone Crusher Parts Manufacturer In China”.

1.” Zhejiang Zhengang Industry“.

  • 20 years in casting cone crusher wear parts;
  • More than 30,000 tons of casting parts;
  • “Shanbao” OEM foundry;
  • Most of cone crusher wear parts are suit for China brand crushers. Such as SBM, SHANBAO, LIMING
  • No website
  • No export department

2. “Hunan Shuangfeng JianYe Industry

  • Since 1985 years
  • More than 10,000 tons wear parts per year
  • Focus on the local market, East South Asia, USA, European
  • Have an export office in Nanjing city

3.” HUBEI JYS ADVANCED WEAR RESISTANT MATERIAL TECHNOLOGY CO.,LTD

  • Since 2013 years
  • 8000 tons of wear parts per year
  • Focus on European market, North America market
  • Have an export office in Nanjing city
  • Fastest growing foundry in casting foundry

4.” Xinfeng Fufeng Metals Co., Ltd

  • Since 2004 years
  • 5000 tons of wear parts per year
  • No website, No export department

5.” Zhejiang Mayang Industries Co.,Ltd

  • Since 1985 years
  • 15,000 tons per year
  • One of reviser of GB/T 5680-2010 Standard of Manganese Steel Casting
  • Most of their parts are export to oversea