CPCS A34 Crawler – Tractor/Dozer Course

1. Introduction

1.1 Prerequisites. There are no formal entry requirements. The minimum requirement is a good understanding of spoken and written English. If you have any concerns about this, please contact our Course booking staff who will be happy to assess your needs.

1.2 Objectives. To provide thorough practical and theory training in operating a dozer, to enable the candidate to competently and safely carry out the role and pass the CPCS Theory and Practical Tests.

Upon completion of the CPCS A34 course, the learner will be able to demonstrate a level of operating ability through safe and productive operation of the dozer. The A34 CPCS module is delivered through a combination of classroom-based tutorials and practical hands-on experience. Our ratio of 2 machines and 3 candidates provides a much greater machine operating experience. We are able to achieve a level of onsite operating ability, allowing the candidate to cope with a variety of tasks in differing site conditions. The course length will vary depending on the skill, knowledge, and experience of the candidate. Typically, the novice course will last 5 days, intermediate 3 days, and 2 days for experienced operators.

1.1. Course Overview

This course is designed to provide thorough practical and theory training in operating a Crawler – Tractor/Dozer to enable the candidate to attain the CPCS Red Operator Card. On successful completion of the Theory & NVD (log book) Technical Test, a CPCS Trained Operator (red) card will be issued. The Crawler Tractor/Dozer course will consist of classroom-based tutorials and practicals. This CPCS Dozer training will give instructions on all aspects of plant Dozer operations and through focused training, will help the candidate to understand the role and responsibility of the plant operator. The CPCS course will also provide the candidate with the basic knowledge and practical skills involved in Dozer operations. At the end of the Dozer course, the candidate will undergo a theory-based technical test. The practical training for the Dozer will be based around typical tasks and underfoot conditions found on construction sites. Tasks will be realistic to the type and scale of work found in the construction industry. Every course candidate will be given maximum support through training to give them the best opportunity to pass the Dozer course.

1.2. Objectives

The candidate will then follow this up with a theory test revision session prior to their CPCS Theory and Practical tests. This will ensure that the knowledge and skills are fresh in their mind, giving them the best possible chance of succeeding in the tests.

– Operation including loading, digging, levelling and dozing, achieved through the following: health, safety and environment knowledge requirements, understanding of differing and correct attachments i.e. blade, angledozer, tracks, 3 point linkage, correct preparation of surrounding area and machines positioned including ensuring no damage to underlying services, understanding correct material storage techniques, support of various machines during work, correct technique for above mentioned operations, understanding limits and instability ranges of differing machines, safe working techniques including assessment and execution of checks in machine and surrounding area, knowledge and understanding of differing operational limits due to ground conditions, bench work of correct and incorrect operational techniques, maintenance and plant identification on this day, understanding the need for and undertaking regular machine maintenance.

– Ensuring the setting and/or handbrake function is applied with an explanation of tracked machine auto-park systems, understanding differing types of steering and best use, effective communication with adjacent and plant controllers.

– Underpinning knowledge: The purpose and uses of differing sizes and types of tractors and dozers, employers’ duties under the act in provision of a safe system of work, PPE and risk assessments in relation to health and safety, knowledge of current H&S legislation, including HASAWA, ACOP, understanding the intent and limits of each machine, preparation for work and travel with an explanation of the mechanisms including crawl, track, tyres, establishing the correct means of assessing the ground conditions and gradients, understanding the need to establish the extent of and position of any underground and overhead services.

The learner is required to pass a health, safety and environment test and a CPCS technical test. The object of the Tractor/Dozer course is to provide the candidate with a thorough practical and theory training in operating a Crawler Tractor/Dozer and to enable the candidate to pass the CPCS Theory and Practical Tests. By the end of the course, the candidate will have an understanding of the knowledge requirements, skills, and safe operating techniques to enable them to become a safe and effective operator. The course covers the following:

1.3. Prerequisites

It is strongly recommended that all those attending this course have successfully completed a Health, Safety and Environment touch screen test within the past 2 years. These tests can be taken at most Pearson Vue testing centres around the country. This is because companies cannot fully apply for NVQ approval for their employees until all those holding operator cards have achieved one of these tests. If the touch screen tests have been successfully completed, then all those attending the CPCS testing will be eligible to apply for the Vocational Qualification. It will be difficult for individuals who are new to the construction industry to gain the required underpinning knowledge to achieve a Vocational Qualification based purely on this course. This is because the CPCS testing requires candidates to complete a log book of work-based evidence, knowledge questions, and site visit practical tests. So unless there is an opportunity to complete these while operating an area crawler/tractor/dozer under supervision, the candidate is likely to be required to complete this process in their own time. An NVQ is extremely useful to those wanting to further their career in the Construction Industry.

2. Machine Familiarization

The A34 tractor-dozer is intended for the earth-moving and grading industry. The machine delivers power, speed, fantastic grading ability, and is finished with a spacious, comfortable operator’s station. The opportunity is formidable to work all day long in a comfortable and productive environment. This machine has made great strides in operator visibility up to the cutting edge. This write-up is specifically about the six-way A34 dozer; however, A34 dozers are also available in an LGP form. The LGP form is designed specifically for dozing applications, typically in the southeast USA. This particular model, the A34, is a machine designed for dozing, line and grade work, and pioneering. The six-way A34 is an exceptionally universal tractor-dozer. The stabilizers are a feature designed for a dozer in order to give the blade more power and tilt to handle a wider range of material. The A34 dozer is equipped with a shuttle shift transmission. This feature is particularly popular with operators as it delivers maximum productivity during grading.

2.1 Equipment Description

2.1. Equipment Description

It is fitted with an open ROPS cab, which can easily be folded down to work under buildings. A cab protection system can also be attached to give additional protection from falling debris when working on demolition sites. All-round visibility is excellent from the cab, but for those potentially hazardous jobs, the machine can be fitted with reverse alarms and/or a flashing beacon. Additional lighting can also be added in the form of cab roof lights or, for working in awkward/enclosed areas, an under-slung lighting system available front or rear.

The tracked undercarriage provides a safe and comfortable method of working on inclines of up to 30 degrees. The hydrostatic transmission, incorporated with the large diameter drive sprockets, provides the machine with excellent traction. The steering is very user-friendly, operable by the left-hand joystick, so this machine can be comfortably operated by either hand.

The A34 Crawler Tractor/Dozer is a tracked machine designed to work on varying underfoot conditions. It has a range of attachments making this a very versatile machine. These include a dozer blade, three different types of buckets, a muck grab, a compaction roller, and a land rake.

2.2. Controls and Instrumentation

A gear position display is located to the right of the steering column and displays whether the machine is in forward or reverse gears. This display will also flash to indicate a transmission fault complaint. To the right of the display is a warning light show, which shows transmission fault complaints during machine operation.

A gear change switch is located to the right of the joystick above the FNR button. This new style gear selection system allows for low/high speed on the go and has a fuel-saving lock-up torque converter function. The torque converter lock-up is automatic in gears 4-6 and switches the transmission between direct and torque converter drive depending on whether the machine is climbing or traveling on the level to achieve the best fuel savings. This function increases available travel power and saves on fuel consumption when traveling long distances.

A twin blade control switch is located to the left of the joystick and is used to change between angle blade and power angle tilt blade positions. Directly opposite of the right joystick is the left joystick, which controls the machine gears and blade functions. This joystick has a quick speed selection thumb wheel and a detent button. The detent button controls the differential steering system and is an automatic setting for use when operating the machine. When the button is pressed, the steering system is engaged and the machine will steer by braking the track on either side of the direction of travel. This is a much easier and less confusing system to use than traditional dozer steering methods. Upon releasing the detent button, the steering system switches off and the machine returns to normal travel mode.

Machine controls are laid out in a very logical, easy-to-use pattern. The machine is controlled by 2 joysticks which control transmission and blade functions. The right joystick controls the dozer travel direction and speed. It has a FNR control button to switch between forward and reverse travel, and a thumb wheel to provide quick speed selection for up and down travel through each gear. This button layout is very similar to operating an automatic car, making it easy to understand and use for beginners.

2.3. Safety Features

The major safety features are: FOPS (Falling Objects Protective Structure) and ROPS (Rollover Protective Structure) protection is provided by a reinforced steel frame in case of accidents when operating on gradients and pushing heavily compacting material. Both these features are tested and certified. Another safety feature is the emergency steering system which is designed to stop the machine should the operator’s control be compromised in any way. This system will bring the machine to a controlled stop and leave it in a safe state. The machine is also fitted with reflective markings and an orange beacon as additional aids to visibility. Please note: all listed safety features are subject to correct and proper usage of the machine. Safety features only work when operators comply with the best practices of use and operation.

3. Operating Procedures

This section has been designed specifically to tell the cardholder that most of the work situations or conditions in which a Crawler Dozer is likely to operate or be used will require operations that are outside its designed capability and therefore judgment needs to be applied in planning and executing these operations. Most of the operations involving a crawler dozer can be considered as a fine balance between tractive capabilities, steering and grade control using the blade. Judgment is always required to judge the capability of the machine and the correct machine set up to enable the successful completion of the operation. It is possible that the correct operation of the machine and blade would involve a different machine configuration i.e. with ballast added or removed, the use of different blade equipment or by pushing from the reverse side of the blade. This type of work is usually preparation or enabling work for other operations and sometimes it may be more practical to use an alternative machine, or to subcontract another operation to a more suitable machine. An understanding of the capabilities of the alternative machine, the economics of subcontracting and the resulting quality and operative safety on the job is important in such decisions.

3.1. Pre-Start Inspection

Function of travel levers, decelerator pedal, and steering pedals: – Travel Levers: – Place transmission in forward or reverse by using travel levers. – The further the levers are pushed, the faster the machine will travel. – Decelerator Pedal: – This is used to reduce the engine speed and the machine travel speed when either of the travel levers are in the neutral lock position. – Pushing the pedal increases the engine and travel speeds. – Steering Pedals: – The machine is equipped with steering pedals which control the steering clutches. – By applying pressure to the pedals, the machine can be steered to the right or the left.

Identify and conduct a check on the instruments: – Amp meter – Oil pressure gauge – Water temp gauge – Volt meter

Inspect and identify the controls in the operators position. Locate and explain the use of the following controls: – Blade lift/tilt – Left and right steering/track pedals – Inching pedal – Decelerator/accelerator control

Inspect and locate the various major components and explain their functions. Identify and locate the major components of the machine: – A forward slash – Cylinder – Track roller – Idler – Top roller – Track pad – Each track has three up rollers – A14

3.2. Starting and Stopping the Machine

There are many procedures which need to be followed prior to starting the machine. Before attempting to start the machine, operators should ensure that all site safety requirements have been adhered to. Ensure that the dozer is on firm, level ground before attempting to start it. Starting the dozer on an incline may result in insufficient oil being supplied to the engine and damage may occur. This is due to the angle that the oil is sitting in the sump. Turn the battery isolator on. If the engine is cold, use the decompression control to ease the strain on the engine when starting. Only use the accelerator and decompression control when starting the dozer with the transmission lever in neutral. Using an accelerator in cold ambient temperatures may result in ‘white smoke’ emissions from the exhaust. This is unburned fuel or diesel mist. Keep repeating this action until the engine starts (it will take some time if new). Once the engine has started, release the decompression control. Note: decompression control can be harmful to the engine if not used correctly. Never accelerate the engine immediately after starting. Engines are designed with oil pressure driven bearings. Accelerating the engine before sufficient oil pressure is present may result in costly damage. Check the oil pressure has reached a sufficient level (and stabilized) before engine revs are increased.

3.3. Basic Operation Techniques

Common mistakes when acquiring basic operating skills are overcontrolling the machine or trying to do too much too soon. For example, when taking on a basic shaping task for the first time, it is often best to position the dozer at one side of the area to be shaped, and then simply drive forwards and backwards over the whole area to track up the ground. This allows the operator to get a feel for the ground conditions and the dozer’s traction and steering capabilities without getting too involved too quickly. Try to resist touching the blade controls at this stage, it is better to get a feel for pushing the machine around – the blade can be used to affect the machine’s pushing and turning capabilities which will be the subject of a later module on more advanced techniques and when first learning it is essential to develop a “feel” for how the machine responds to the controls. Mastering the art of straight driving and manoeuvring takes time and practice and may not come naturally to some operators. The various effects of subtle and gross steering control movements and the combination of steering and direction of travel on the machine’s movement may be quite confusing to a beginner. An exercise such as pushing up a long even spread of material and then spreading it back out straight again can be useful for developing control and coordination. This is an area where the operator can often learn a lot by watching an experienced operator at work.

3.4. Manoeuvring and Turning

Avoid pivot turns where possible. These types of movements are usually unstable, especially when the load is unbalanced, causing slippage and loss of control. If a pivot is necessary with a blade load, the load should be dropped and the turn should be made without the blade on a straight run through, then backing up to pick the load with the blade. The steering clutch and braking system available on crawler tractors should always be used instead of forced steering movements with the blade or track, which causes high wear and damage to the undercarriage and reduced life of steering mechanisms.

When repositioning the machine or traveling with a load, it is important that the operator maintains full control of the machine and load at all times. The operator must be aware of the ground conditions to ensure that traction will not be lost when pushing or pulling loads, especially in adverse conditions. When the machine is tracking up or down slopes, the clutch should be used instead of the brakes to prevent wear and damage to the steering clutches and final drives. The operator should always plan the route and try to keep steering to a minimum, making full use of the straight blade and avoiding abrasive steering, which will cause wear to the undercarriage and more fuel consumption.

4. Advanced Techniques and Applications

The testing also highlighted the fact that an S dozer with a straight blade is not suitable for hard digging operations due to the lack of blade control. For hard digging, the best results are achieved with a P dozer and power angle tilt blade. With the skid steer and compact tracked loader now challenging the dozer’s traditional role as the prime mover for dirt, it is important that dozer operators are able to choose and use the most effective machine and attachment for the task. This will maximize the productivity and cost-effectiveness of dozer operations.

An afternoon of hands-on testing yielded some insightful results. An LGP dozer equipped with a 6-way blade will have a lower hourly cost for grading operations than a skid steer with a 6-way blade. This is due to the increased efficiency and production of the dozer. The same can be said for back dragging operations, where the dozer also provides a wider blade and better visibility. However, the skid steer has the ability to easily remove the tracks and utilize its undercarriage for finish grading operations. This is a function that a crawler dozer cannot perform cost-effectively due to excessive track wear.

There are many attachments available for a dozer, some of the most common include: winch, ripper, and a cushion blade. These attachments enable the dozer to undertake a wide range of tasks including logging and pushing oversized loads. Arguably, the most important attachment for power dozing is a 3 or 4 shank ripper. This is used for breaking up hard ground in preparation for pushing.

4.1. Working with Attachments

Substantial increases in machine performance and task efficiency can be made through correct use of the control systems. This is particularly beneficial for fine grading and dozing tasks. By altering and customizing the assignment of the control lever, pedal and buttons, work tool control and maximum response can be maximized. Customizable control assignment allows the most comfortable and ergonomic control position for the operator, in turn reducing operator fatigue and increasing task efficiency. Simulation and teach functions are useful for training and becoming accustomed to the optimal control methods and systems.

The D6N and D6R both are suitable for brush clearing, ripping/scarifying and power grading tasks. These tasks can be completed through the use of rippers, blades and blades with tiller control. The work tool control system and blade response will need to be set to approximate in order to get the most effective and efficient results. Alternatively, the machine is also suitable for pallet fork and winch application, although it is more cost efficient and versatile to order a skid steer loader for these tasks. Stepless control and multiplier can be utilized to get the most effective results for brush clearing and power grading due to the D6R AHC.

Attachments extend the machine’s use and potential. A very wide range of attachments and tools are available to perform various tasks. However, special attention needs to be paid when ordering the attachment to ensure that the machine is available and suitable. Attributes to consider are machine compatibility, hydraulic flow and pressure to ensure that the attachment operates efficiently. Time and consideration needs to be taken even before the job has commenced, the range of tasks need to be considered to ensure that the most efficient and economical attachment is used.

4.2. Operating on Different Terrains

Operating in wet and boggy ground can be a difficult proposition in a lot of cases resulting in the need for reclamation of the land. For standard wet ground which is still feasible to work on, it is recommended that some form of grip type attachment is used as standard tracks are usually inadequate resulting in track slippage which causes damage to the machine’s undercarriage. Dozers are capable of wide track modification to increase flotation by reducing ground pressure, though this is only recommended if this is a regular requirement for the machine. This can be implemented using wide standard track plates, but there are also tracks available which actually widen the track’s footprint reaching two and a half times the machine’s width. Other alternatives are rubber tracks which are effective to a point but are mostly used on mini dozers due to a loss in push loading ability.

Differing terrains offer a varying degree of complexity when working with a dozer. An obvious example is trying to work on a slope. This is not recommended as standard dozers are not designed to work safely on slopes. However, if it’s vital to do so, it is recommended that a ‘side slope shoe’ is attached. Other methods to improve safety and effectiveness are to use a bulldozer instead of a standard dozer so the load is nearer the machine, therefore increasing stability. If there is no alternative to using the standard machine, a system using an ‘angledozer’ can be used with an attached winch and an anchor point at the top of the slope to winch the machine up. It is also worth considering a small mini excavator equipped with a plough/dozer blade.

4.3. Handling Various Loads

Step one in the operation of loading and carrying said materials is the scraping of the materials with the blade. This then moves on to the various pushing operations. The first push is known as side casting and involves pushing the materials up to a point where they are deposited into a pile. This is repeated until the pile is large enough. The next step is clean-up pushing, which requires the dozer to push the materials to a different location.

Differing from the rippers and winches found on wheeled tractors, crawler dozers are often equipped with a blade on the front. Dozers are commonly used for grading with the blade. However, in this instance, the term “blade” will refer to the dozer as it is used for scraping and pushing materials from one location to another. This is known as a push loading operation, and a specific type of blade known as a load and carry blade is best suited for this operation. A load and carry blade has the capability to change the pitch of the blade, so it is best suited for the various stages of scraping and then carrying loose materials. Where standard blades of fixed pitch are best suited for pushing materials.

It is to be noted that using a winch is a last resort in dozer operations. However, if a tracked dozer is faced with pulling a very heavy load such as a D8 or 9 dozer up a slope, a winch and a tow chain are often the only way to get the job done. This should be done with much caution.