Managing Fluid Cleanliness

1.0 Introduction

This Best Practice provides an overview of the importance of maintaining clean fluids and offers suggestions on how best to achieve that. Detailed information can be found in the specific Best Practice publications cited.

Minimizing machine operating cost is critical to minimizing cost-per-ton. Aside from the cost of tires, fuel, and operator, about 70% of total machine operating cost is the life cycle costs of machine powertrain components. On a typical large mining truck, the cost distribution is as follows:

- Engine 40%

- Transmission & Torque Converter 10%

- Final Drive & Differential 40%

- Miscellaneous 10%

Component life cycle cost is roughly defined as cost to rebuild the component divided by actual component life in hours. Example:

($100,000 rebuild cost ÷ 10,000 hour life = $10 hour life cycle cost)

Extending the life of a component is the most important factor in reducing its life cycle cost. This does not mean simply extending overhaul intervals and allowing components to wear more severely. It means implementing a strategy to reduce the rate of wear and achieve longer

component life without incurring excessive wear.

2.0 Best Practice Description

The best way to minimize power train cost per hour is to extend component life and utilize the value built into the component. The most effective way to accomplish this is to operate the component with very clean oil throughout its entire life.

Fluid cleanliness management is a strategy to:

• Remove component and/or system break-in debris as quickly as possible on new and rebuilt components.

• Maintain very clean oil in the component and/or system throughout the entire PM interval and entire component life.

3.0 Implementation Steps

3.1 Dealer & Customer Commitment

3.1.1 Understand the Causes of Component Wear and Failure

• Reference Improving Component Durability booklets

(See Section 6.0 Supporting Attachments)

• Tolerate Early-Hour Filter Plugging

• Use Off-Board Filtration to Remove Break-In Debris

3.2 Bulk Fuel Filtration

For a variety of unavoidable reasons, fuel delivered to mine sites is usually contaminated with dirt and water. Because fuel is a very low margin commodity, suppliers almost never provide adequate bulk fuel filtration or exercise recommended storage practices. As a result, mines receive and use contaminated fuel, resulting in premature injector failure and wear out. This results in excessive fuel consumption and often results in mid-life injector set replacement.

The fuel filters on the machine are designed to provide final filtration for moderately clean supply fuel. Machine filtration is not intended to clean fuel contaminated with large amounts of dirt and water. If contaminated fuel is used, the capability of the onboard filtration is overwhelmed and injectors either wear out prematurely or seize.

Bulk fuel filtration has been used in the aviation industry for more than 50 years to address the same problems. Caterpillar has now adopted this proven technology to help mining customers clean contaminated fuel.

Bulk fuel filtration consists of high capacity filters, which remove both excess dirt and water from the supply fuel before it is put into the machine.

Caterpillar has engineered a packaged system to remove both dirt and water. It requires very little maintenance and contains safeguards to prevent contaminated fuel from passing through the unit. The unit is self-contained on a skid and is located between the fuel storage tank and fueling station. It provides single pass filtration, and is offered in four sizes depending on the maximum flow rate of the fuel delivery system.

3.3 Bulk Oil Filtration

A widespread misconception is that new oil is automatically clean because of its appearance. In fact, nearly all new oil is contaminated to some degree with dirt, metal particles, plastic, water, or other foreign debris. These contaminants are introduced in the transportation and storage process from the time the oil leaves the refinery until it is used by the end-user.

Very little new bulk oil meets the recommended Caterpillar cleanliness spec for new oil of ISO16/13. This includes oil delivered in bulk tanks, steel barrels, plastic cubes, and small plastic containers.

Unfiltered new oil should never be taken directly from the container and placed into the machine.

This is true whether the oil is being used for refilling a compartment at an oil change interval or simply topping off a system.

A variety of bulk oil filtration methods are available and the best one for each situation is dictated by factors such as: volume of oil used, location, available infrastructure, and cost.

3.4 Off-Board Machine Fluid Filtration

Filtration carts can make a major contribution to extending component life. Many mines and Caterpillar dealers use filtration carts for the major systems during normal preventive maintenance. Carts are connected to major systems (rear axle, transmission, hydraulics, steering) and operate unattended while PM services are completed.

3.5 On-Board Machine Fluid Filtration

The micron rating of filters on many mining machine systems are sized so as not to plug during the initial break-in period on new machines. This does not provide optimal filtration capability to maintain very high levels of oil cleanliness after the break-in period is complete.

The most aggressive approach to removing break-in debris as quickly as possible and maintaining the highest level of fluid cleanliness is to use Ultra-High Efficiency (UHE) 6-micron filters in place of standard filters for all machine systems except the engine. Because these filters effectively trap very small particles, some filter plugging will occur during the initial PM periods.

3.6 Breather Filters

Dust entering fluid compartments through inefficient breather filters is often a source of fluid contamination. This can be easily prevented with the use of spin-on High Efficiency 4-micron fuel filters as breathers for all compartments. When used as fuel tank breathers, HE filters have reduced or eliminated premature fuel filter plugging in extremely dusty applications. HE fuel filters are also larger than standard breathers and have much greater capacity.

3.7 Measuring Oil Cleanliness

Component life is maximized when high levels of fluid cleanliness are maintained. The ability to effectively and consistently measure debris in fluids is a basic requirement of managing fluid cleanliness. Tracking fluid particle data is one way to monitor component health. If a particle count raises sharply, an SOS sample can be used to determine the specific wear metal showing elevated levels.

4.0 Benefits

Improved Durability

-Up to 1/3 longer life of powertrain and implement hydraulic components

-Does not apply to engine due to soot in lube oil.

Improved Reliability

-Reduce or eliminate repairs caused by contamination debris.

Improved Parts Reusability

-Reduced wear rates of internal parts improve reusability.

5.0 Resources Required

• Bulk Fuel Filter Coalescer

• Bulk Oil Filtration

o Permanent filtration installation (or)

o Portable filtration carts (or)

o Barrels (or)

o Cubes (or)

o On-Machine (or)

o Off-Board Filtration Carts

• Portable Particle Counters

• Particle Count Data Management Software

• Improving Component Durability Training Booklets

6.0 Supporting Attachments

See Component Life Management Strategy Document (Click on Attachments tab within this document to view attached file)

Improving Component Durability booklets

7.0 Related Best Practices

0808-2.10-1006 -Bulk Fuel Filtration

0808-2.10-1005 -Bulk Oil Filtration

0808-2.10-1002 -Off-board Fluid Filtration

0808-2.10-1002 -On-board Fluid Filtration

0808-2.10-1004 -Breather Filters

0808-2.10-1001 -Measuring Oil Cleanliness

8.0 Acknowledgments

This Managing Fluid Cleanliness Best Practice was authored by:

Dick Douglas

Market Consultant

Caterpillar Global Mining

Douglas_Richard_D@cat.com

1-309-675-5699

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Optimizing Component Removal & Installation Quality through Customer Certification

1.0 Introduction
Proper Major Component Removal and Installation (R&I) practices are vitally important for component reliability and life. Mistakes made during component removal and installations are a leading cause of early hour failures or shortened life. To ensure that component removal and installation is performed following a well-defined process, many Caterpillar dealers have provided training, and in some cases, even “Certified” customers as qualified to perform component R & I.

2.0 Best Practice Description
Caterpillar Dealers have invested considerable financial and manpower resources into creating major component rebuild capabilities that deliver cost efficient, high quality for their customers. A poorly performed removal and / or installation process can negate the efforts put into component rebuild.
Some dealers have taken steps to control the R&I process in order to protect their investment in the rebuild and also to ensure that the component delivers expected reliability and life.
Typical actions have included:
• Dealer must do the component installation.
• Dealer must supervise the installation
• Dealer trains and certifies the customer to perform component removals and installations.

3.0 Implementation Steps
Start with a process audit by the dealer to the customer. Then provide subsequent training on proper major component removal and installation. The most important success factor is a common, shared objective by customer and dealer. A shared objective will ensure component reliability and life through proper R & I practices.
Implementation Steps:
1. Customer Shop Audit / Inspection
a. Tooling
b. Contamination control practices
c. Cleaning equipment
d. R & I area
e. Component storage / staging

2. Training:
a. Failure Analysis – Determine cause for removal
b. Document removal – hours, history, oil analysis, particle count
c. System inspection and clean up process– debris removal
d. Rebuild related system: radiator, coolers, pumps, hoses, and air intake, etc.
e. Installation procedures / checklists
f. Test and brake-in procedures
g. Fluid cleanliness - ISO particle count specifications
h. Standardized installation parts kits (see example to the right)
i. Record keeping –installation checklists, parts Bill of Materials, particle count, test results.
j. Dealer feedback – completed installation checklists, initial SOS

During replacement of any major component, attention should be given to the related systems & sub-components, which may impact performance and life of the newly replaced component.

4.0 Benefits
• Improved reliability
o Improper installation is a leading cause of early hour component failures and shortened life.
o Proper installation positively impacts:
�� Machine availability, which impacts production rates at the site.
�� Maintenance costs by avoiding unnecessary costly repairs.
• Improved durability.
o Proper installation helps to maximize component life and reduce cost per ton.

5.0 Resources Required
• Dealer must have a qualified inspector and training instructor. In addition, training materials may need to be developed.
• Customer may require improved tooling or shop facility improvements.

6.0 Supporting Attachments / References
References:
See also, Improving Component Durability – Component Removal and Installation - SEBF1017

This booklet explains how problems in the component removal and installation process often cause components to fail.
The booklet contains 24 pages of high -quality, full color graphics and text, which provide an easy -to -understand explanation of:
• Common failures caused by poor R&I practices
• Importance of the R&I process
• Best practices
• Risk management in cleaning contaminated systems
 

The booklet also explains the how the component replacement process has evolved from the days of the early track-type tractors to today’s modern machines with electronically controlled engines and transmissions. A common sense approach to risk management is also discussed regarding how much time to invest in system disassembly and cleaning after a catastrophic component failure.

The booklet is intended for all levels of dealer and customer personnel involved with the operation and maintenance of earthmoving equipment. It is particularly useful to those who manage equipment operation and maintenance

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Replace Fluid Hoses During Component R & I

1.0 Introduction
When a major component is removed for a PCR rebuild, this is an ideal time to change all fluid line hoses in the major component compartment area. This is especially true for engine Removal and Installation (R&I) where hoses are very difficult to access with the engine in chassis.
This practice prevents:
- Hose failures,
- Contamination, and
- Loss of fluid and machine downtime to replace failed hoses.

2.0 Best Practice Description
This Best Practice is to replace all fluid hoses in a major component compartment area while the component is out of chassis for a PCR rebuild. Access to the compartment is greatly improved, and thus labor required is a fraction of the labor necessary to change a hose with the component in chassis. In addition, this practices provides a planned before-failure replacement schedule for the machine hoses and fluid lines.

3.0 Implementation Steps
Required process changes include:
1. Add "Replace Fluid Hoses" to the R&I checklist
2. Add hoses and clamps to the R&I parts kit and checklist,
3. Add OHT hose routing diagrams to the R&I forms kit. Hose routing diagrams are contained in the machine parts manual.

Example: Parts Book Hose Part Numbers and Routing Example
 Add OHT hose routing diagrams to the R&I forms kit.

4.0 Benefits
• Prevent unplanned hose failures
• Better machine availability
• Increased production

5.0 Resources Required
Time to identify parts and information required to perform the hose replacements.

6.0 Supporting Attachments & References
None Applicable

7.0 Related Best Practices
None applicable.

8.0 Acknowledgments
This Best Practice was authored by:
Dale Brehm
Caterpillar Global Mining
6 Sigma Black Belt
Brehm_Dale_E@cat.com
+1 309 675 6325

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Bulk Fuel Filtration

1.0 Introduction

Modern fuel systems use electronic unit injectors which deliver precise amounts of fuel at pressures up to 25,000 psi, and control injection timing to within thousandths of a second. Electronic unit injectors control the performance and fuel economy of the engine and are expensive to replace when worn. A rough estimate of injector replacement cost with parts and labor is approximately $1,000 per cylinder. And, of course, there’s the cost of taking a machine out of production.
Injectors operated on clean fuel should last through engine overhaul. The fuel filters on the machine are designed to provide final filtration for moderately clean supply fuel. Machine filtration is not intended to clean fuel contaminated with large amounts of dirt and water. If contaminated fuel is used, the capability of the onboard filtration is overwhelmed and injectors either wear out prematurely or seize.
For a variety of unavoidable reasons, fuel delivered to mine sites is usually contaminated with dirt and water. Because fuel is a very low margin commodity, suppliers almost never provide adequate bulk fuel filtration or exercise recommended storage practices. As a result, customers receive and use contaminated fuel, resulting in premature injector failure and wear out. This causes excessive fuel consumption and often results in mid-life injector set replacement.
Bulk fuel filtration has been used in the aviation industry for more than 50 years to address the same problems. Caterpillar has now adopted this proven technology to help mining customers clean contaminated fuel.

2.0 Best Practice Description

Bulk fuel filtration consists of high capacity filters, which remove both excess dirt and water from the supply fuel before it is put into the machine.
Caterpillar has engineered a packaged system to remove both dirt and water. It requires very little maintenance and contains safeguards to prevent contaminated fuel from passing through the unit. The unit is self-contained on a skid and is located between the fuel storage tank and fueling station. It provides single pass filtration and is offered in four sizes depending on the maximum flow rate of the fuel delivery system.

2.1 Dirt (Particulate Filter)

4-micron, beta 200, full synthetic particulate filter elements remove dirt in a single pass. Filter change intervals of up to one month depending on the level of fuel contamination.

2.2 Water (Coalescing Filter)

Coalescer unit contains multiple elements capable of removing up to 3% water by volume to 1,000 ppm (0.1%) or less at the rated flow. Water is automatically drained, requiring no manual intervention. Coalescing elements do not plug and usually require changing only once a year.

2.3 Flow Control Valve

An automated flow control valve slows down or stops fuel outlet flow if particulate filters plug or there are massive amounts of water in the fuel. This assures only clean fuel leaves the unit.

3.0 Implementation Steps

Technical information and pricing on these units is available from Cat Global Mining and the Cat Filters and Fluids group. Unit sizing is determined by the maximum flow rate of the fuel delivery system. Four different sizes are available:
50 &100 GPM
Small units intended for remote day tank applications or for portable use on a fuel truck where fueling is done manually.
200 GPM
Intended for fuel stations using fast-fill where maximum flow does not exceed 200 gpm. This unit will handle trucks through 793.
300 GPM
Intended for fast-fill of 797 trucks where fuel flow rates exceed 200 gpm.

4.0 Benefits

Supplying clean fuel to the machine permits the onboard fuel filters to function properly without plugging.
Most injectors should last to engine overhaul and provide improved long-term fuel economy and engine performance.

5.0 Resources Required

Permanent installation requires only a small concrete pad downstream of the bulk storage tank and supply pump. The unit is installed in series in the fuel supply line to the fueling station.
A water container is required nearby to store the waste-water removed from the fuel. No electrical power is required for the unit unless it is used in freezing climates.
An optional electric heating element is available to prevent water from freezing in the bottom of the coalescer tank.

6.0 Supporting Attachments

Component Life Management Master Document, PDF file. (Click on Attachments within this document to view)
An explanation of how the unit works, along with visuals is available in the “Managing Fluid Cleanliness” booklet form SEBF1020.

7.0 Related Best Practices
0806-2.10-1005 -Bulk Oil Filtration
0806-2.10-1000 -Managing Fluid Cleanliness

8.0 Acknowledgments
This Bulk Fuel Filtration Best Practice was authored by:
Dick Douglas
Market Consultant
Caterpillar Global Mining
Douglas_Richard_D@cat.com
1-309-675-5699

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Large Mining Truck - Truck Overload Policy "10/10/20" (Revision #4)

Gross machine operating weights have been frequently misapplied on off-highway trucks in the market place. For example, maximum, which means, “not to exceed”, has been inappropriately used as the target. Regulatory and product support considerations have prompted some dealers and customers to request quantification of “acceptable” payloads on Caterpillar’s Mining Trucks. Technically, the correct answer is that any overload will adversely affect component life and potentially affect steering & braking performance. If the overloading is severe enough, the truck will be unsafe to operate. The following is intended to communicate guidelines of the 10/10/20 policy, the relationship between payload and performance, and the maximum operating weights and the associated payload policy that Caterpillar is using in support of warranty considerations and maintenance and repair contracts (MARC's) for Mining Trucks.

Caterpillar’s payload overload policy, referred to as the “10/10/20” policy, states that “The mean (average) of the payload distribution shall not exceed the target payload and no more than 10% of payloads may exceed 1.1 times the truck target payload and no single payload shall ever exceed 1.2 times the target payload.”

KEY ISSUES:
1. Target payloads for various Caterpillar truck models, when equipped with different truck body configurations are outlined in the Table 1 at the end of this document. Site conditions may dictate that underloading is more economical than loading at the target payload.
2. Gross machine operating weights and associated payloads are continually being updated. For the latest approved mining truck gross operating weights with the target and maximum payload visit: https://mining.cat.com/products/trucks.html
3. Actions required to maintain brake certification to SAE & ISO standards and British Columbia (B.C.) codes are addressed.
4. Component life is directly related to gross machine weight and associated payload. Therefore, specific support commitments will be required from Caterpillar and it’s dealers for given applications.
5. In this policy, target payload is the difference between gross machine operating weight and empty operating weight. The mean (average) payload distribution shall not exceed the target payload. Reducing empty operating weight provides for increased payload capacity, and an increase in empty machine weight decreases payload capacity. Empty operating weight includes bare chassis plus 4% for normal debris accumulation and full fuel.
6. This policy is applicable to current production models with the latest power train and structural improvements and non-current products updated to the latest improvements. The power train improvements required under the 10/10/20 overload policy are outlined at the end of this document.

PAYLOAD DISTRIBUTION
Target payload is defined as 100%. The target should always be 100. Caterpillar's 10/10/20 policy allows for no more than 10% of the loads to fall in the 110% to 120% range (yellow region). No loads should ever exceed the trucks steering and braking certification. Exceeding the steering and braking certification would make the truck unsafe to operate.

Payload Distribution

COMPONENT LIFE vs. PAYLOAD
demonstrates that the component life is decreased significantly when overloaded 10% to 20%. The rate at which component life decreases as a result of overloading is greater than the rate at which component life increases as a result of underloading.

Component Life vs. Payload

There are a few basic rules of thumb related to component life vs. payload. First, engine life is directly related to fuel burn. If payload is increased, the truck gets heavier creating a higher duty cycle resulting in greater fuel burn and shorter life. The torque converter and transmission life are related to torque and again as payload is increased the truck gets heavier. More torque is required to move a heavier truck resulting in shorter torque converter and transmission life. The lower powertrain life is related to load and speed. A heavier truck puts more load on the lower powertrain and again the results is a decrease in component life.

PLACEMENT OF PAYLOAD
Not only is component life impacted by the amount of payload, but it is also impacted by the placement of the payload. A decrease in component life will occur from improper load placement. Specifically, there are three types of improper load placement, load shifted towards the front, load shifted towards the rear, and load shifted towards the side. All three types of improper load placement negatively impact frame and body life. If the load is shifted towards the front, the front brakes, bearings, front tires, steering, hydraulic hoist, body rest pads, and body canopy will be negatively impacted. Trucks with correct load placement and incorrect load placement with the load shifted towards the front.

Side View of Load Placement

If the load is shifted towards the rear, the final drive and rear tires will be negatively impacted. Furthermore, the payload will become unstable and dribble off the back of the body. Trucks with correct load placement and incorrect load placement with the load shifted towards the rear.

Side View of Load Placement

If the load is shifted towards the side, the final drive, bearings, hoist cylinders, and pivot bore areas will be negatively impacted. Trucks with correct load placement and incorrect load placement with the load shifted towards the side.

Rear View of Load Placement

777D & 793C
Note that modification to brake service procedures is required to maintain certification on 777D and 793C models. Specifically, the brakes must be rebuilt at 75% brake wear to ensure that the parking brake will hold in grade per ISO, SAE, braking codes. A measurement instruction has been issued in conjunction with this overload policy. This action enables the brakes to be certified to SAE and ISO standards at up to 1.2 times target payload.

TIRES AND RIMS
It is recommended that users of this policy contact their tire supplier and rim supplier, if other than Caterpillar, to discuss application, site conditions, haul roads, and allowable tire loads before adopting this policy.

TARGET AND MAXIMUM PAYLOADS BY MODEL
The following table is for a representative vehicle configuration. All weights are dependent on chassis configuration, fuel tank, body type, tires, and optional equipment selected.

Overload is a major factor in life shortfalls of planned component replacement goals. Haul road conditions, machine maintenance, and operation techniques are also significant factors.

POWER TRAIN IMPROVEMENTS REQUIRED UNDER OVERLOAD POLICY
797A Mining Truck
• Depending upon the serial number and configuration, existing 797A’s have an overload policy ranging from 10/10/11 to 10/10/20. Most customers with 797A’s have the option to upgrade to 59/80R63 tires so long as other changes are made to the chassis. For information about changes to 797A’s that impact payload and the overload policy contact a mining truckmarketing representative in Decatur.
793 Mining Truck
• Larger wheel bearings – production 10/96
• 20mm wrapper on fabricated wheel – production 1/96
• RAX filtration – production 7/95 (cost to add already paid by Caterpillar)
• Differential ring gear shroud – production 7/95
• Wheel bearing preload adjustment – production 12/97
789 Mining Truck
• Cast wheel with larger wheel bearing – production 10/97
• Differential ring gear shroud – production 11/95
785 Mining Truck
• Cast wheel with larger wheel bearing – production 3/97
• Differential ring gear shroud – production 12/95
• Enlarged wheel bearing retainer holes – screens removed – production 3/98

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