CPCS A06 Concrete Pump – Truck Mounted Boom Course

1. Introduction

This course will be a two-day course. The first day will consist of modules one through seven, and the second day will consist of modules eight through twelve, including the written and practical exams.

This course is designed to have a hands-on practical learning experience as well as a classroom theory learning experience. Each module has two parts: the first part is the theory, which will be held in the classroom. The second part is the practical experience where each operator will participate in operating the equipment throughout different scenarios. The course is designed to have three to six operators per class. This will allow for more personal one-on-one learning and a better quality of training.

This course is designed to assist operators in understanding the functions, safe operation, and maintenance of truck-mounted concrete pumping equipment. It is recommended for potential operators who have at least 3 months of experience as a concrete pump operator. This course is not designed to be a substitute for the manufacturer’s manual, as it will be used as a reference guide and an aid for learning the course material. All trainees should receive the manufacturer’s manual and be advised to take it home and read it whenever they have the opportunity throughout the course and at work. This will assist in reinforcing and retaining the course material and help with daily operations and troubleshooting of the equipment.

1.1. Course Overview

The CPCS truck mounted boom type concrete pump course is offered to candidates of all experience levels from novice to experienced. For novice candidates, there is a further option for additional training linked to a red CPCS trained operator card.

– Two days training with one day CPCS technical testing. – The first day is for training which includes practical and theory including rigging and slinging. – The second day is for further training, the completion of a log book, and confirming that the candidate is ready to take the technical test.

The CPCS truck mounted boom type concrete pump course is based on the CPCS job role for concrete pump operator and incorporates the CPCS technical test at the end. The content of the course will prepare the candidate for the CPCS technical test and consists of the following:

This course is designed to ensure that the operator of truck mounted boom type concrete pumps is able to operate competently, safely, and efficiently. The course is aimed at experienced operators with limited or no formal operating instruction. Candidates must have a minimum of 6 months operating experience (any other types of plant) and passed the CITB Health, Safety, and Environment test within the last 2 years.

1.2. Benefits of Truck Mounted Boom Concrete Pump

Truck mounted boom concrete pump offers a range of features for pumping concrete at various sites. Although they are not as well known as line pumps, there are many advantages to using a boom pump to place concrete. A5 Pumping have a range of boom pumps which can access sites with restrictive access issues. Our Z and Multi-Fold boom pumps can unfold in restricted spaces providing a solution to the access issue. This in turn can save you additional costs incurred from excavation work to create access ways. Most conventional ways of placing concrete such as using wheelbarrows and dumpers can be hard work and very labor-intensive. This can be hard to coordinate and ensure health and safety requirements are met. Boom pumps can place concrete at a far greater rate, sometimes many cubic meters per hour. This can cut placing time and labor costs dramatically. Boom pumps are a highly versatile and cost-effective form of placing concrete. The reach of a boom pump can save having to hire additional plant to place concrete, i.e. cranes or dumpers, and transport and place concrete in a more labor-intensive and costly method. Boom pumps can place concrete in most locations, whether it be down a hole or up and over an obstacle. Concrete can be placed at a vertical distance of 100m and a horizontal distance of 400m. Boom pumps can also be used for a variety of different jobs, including vertical or overhead, and with a variety of different mixes from harsh slump to lightweight. Because concrete placement is fast and precise, additional forming and finishing can go ahead sooner with less delay due to the concrete setting up. This means a more efficient use of time for other trades to be working.

1.3. Importance of Proper Training

Without the proper training, the operator and those working around the unit are at risk. The concrete pump and the principles of using it are relatively simple; however, the skills required to do it well are very specific and quite rare. The ability to read the conditions correctly and know instinctively whether the concrete mix is right or if there is a better place to put the pump are things that only come from years of experience. If an operator picks up bad habits because they were never properly trained, it will create issues for the rest of their career. This can lead to damaged machines, wasted materials, and disputes with other workers. An untrained operator will create a less efficient jobsite and end up costing a lot of time and money. Initial training is the only way to ensure quality work and efficiency from the start.

It is essential to gain training prior to operating any sort of machinery. The size and complexity of the equipment will indicate what form of instruction is required. Truck mounted boom concrete pumps could require numerous kinds of training such as a national heavy equipment operators training (NHEO) certification, a hydraulic boom truck safety course, and/or a mobile crane operator training.

2. Safety Procedures

2.3 Safe Operating Practices Concrete pumps and boom trucks should only be operated by legal and qualified operators. It is illegal to operate machinery in a manner that may be a risk to the safety and health of persons, and it is an offence under section 17 of the Health and Safety at Work etc Act 1974. Before operating the concrete pump, all personnel involved in the operation or erection of the pump shall ensure that they have read and understood the manufacturer’s instructions—this may be an instruction manual provided by the manufacturer or an instruction and demonstration by a competent person who is familiar with the model of pump. The demonstration should be a safe system of work.

A concrete pump is a machine and can fail at any time. If the operator is unable to carry out any work on the pump or any of the safety procedures listed in this training course, he should stop the machine and refuse to carry out the task. He should then report the problem to his supervisor or person in charge, but it is not his responsibility to carry out any repairs. This shall be done only by a competent person taking account of the hazards and risks. (Refer to regulations 5 to 8 of the Supply of Machinery (Safety) Regulations 1992)

2.2 Pre-Operational Inspections Prior to the pump being taken to the job site, the pump owner or operator should complete a visual inspection. Once the pump has been moved to the job site, a thorough inspection including all of the maintenance items in this training course shall be completed before any concrete is pumped through the machine. These inspections should be completed on a daily basis or at the beginning of each shift.

Personal Protective Equipment (PPE) personnel should wear proper PPE when operating or working around the concrete pump. This will include hard hats, safety glasses, gloves, steel-toed work boots, and long-sleeved shirts and pants. Depending on the job site, concrete pumpers may be required to wear hi-visibility safety vests. Pump owners and operators should consult the MSDS for any chemicals present on the job site and be prepared with the proper PPE.

2.1. Personal Protective Equipment (PPE)

When a person works in a construction site, workers need to pay more attention to their safety. This is because the construction site is a place that has a high level of risk and sometimes has a danger that can threaten the safety of workers. There are many ways to prevent accidents at construction site, one of them by using Personal Protective Equipment (PPE). PPE is the tools that are worn to ward off potential hazards. The use of PPE is included the last in a series of efforts down the risk of accident. The main purpose of using PPE is to minimize the potential hazards faced by the construction worker. By minimizing the potential hazards, it means that PPE also minimize the likelihood of accidents that injuries by labours. Wear PPE provides a sense of security and convenience for workers to do the activity. With the use of Personal Protective Equipment (PPE), workers will be more secure from the threat of the risk of injury construction. PPE is the personal gear that’s worn to shield against risks. The main reason for specification for PPE is to spell out the nature of the gear and its use. So, PPE must present a form of excellence which offers higher protection than regular clothing. PPE must cover the whole body from head to toe. But not all PPE should be worn simultaneously, each construction work has a different type of job risk level, some to a small level of risk and there is also high. So the wearer must adjust the PPE to the level of risk he faces in his job. PPE is used based on the consideration of the key to prevent workers from the risks that cannot be eliminated or controlled.

2.2. Pre-Operational Inspections

Check the relevant Plant Operator manual to ensure the machine is being checked to the correct specification. Any defects on the machine should be recorded and categorised as: a) a defect that could create a risk of danger to health and safety of an individual which must mean that the defect must be rectified before the machine is put into service, b) a defect or defects which needs monitoring to ensure it deteriorates to a level where it is considered it would create a risk to health and safety to an individual or c) a defect that does not affect the health and safety of the operator or anybody near the machine but the cost to repair or replace the item does not justify taking the machine out of service. Step ‘c’ defects should be monitored on a more frequent basis to ensure they do not move into category ‘a’ or ‘b’. At the start of each shift or continuous use of the machine, a simple written or visual check should be made to ensure that the defect has not deteriorated into a higher risk category. This inspection should involve checking the defects and carrying out the checks detailed in the following inspection and maintenance section to ensure that the condition of an item has not deteriorated since the last check.

Operational and emergency controls are legible, in English and function correctly, whilst the security devices fitted by the manufacturer are in place and fully functional. Safety decals are present and legible in English, and if there are any warnings specific to certain attachments, these attachments are covered by the warning.

Conduct a visual and audible inspection. Ensure all items do not show signs of wear which could reduce stability at any time whilst in use, no alteration to the machine has been made in any way that may affect the stability and that replacement parts are of the same quality as the original manufacturers.

2.3. Safe Operating Practices

Operation near overhead electrical cables The principal hazard here is the risk of contact between the end hose and the boom pipe or the placing hose and an overhead electrical cable. This can cause electric shock or, at worst, electrocution. Some cables will be at their correct height above ground level with warning notices attached. If this is the case, the following safety issues need to be considered: – Horizontal distance of boom and hose from the cable – as a general rule, no concrete pumping component should be within a 4-meter radius of a vertically projected cable position. – Additional precautions such as barriers or safety observers.

General This section outlines safe practices that should be followed when operating a concrete pump – truck mounted boom. A safe practice is a procedure that will not expose the operator or the general public to the risk of injury or damage and will meet the requirements of the current legislation. Safe work practices require pre-planning to devise methods which will eliminate or reduce risk to an acceptable level. A safe work method statement should be included. This is a procedure based on legislation, a code of practice, etc., which defines the safe way to carry out a job based on a risk assessment and a sequence of steps. Safe work method statements are required for high-risk construction work.

2.4. Emergency Procedures

Lock off & Tag-Out – Isolate any electrical or diesel-driven machines by removal of the key and in the case of electrical equipment, lock out the electrical supply at the distribution board and remove the fuse, placing it in the pocket of the person responsible for changing it. On each occasion, the plant or equipment is only to be restarted by the person who shut down.

Air Line Blowing – In the case of a blowout due to a blockage in the air line, make sure the area is clear of all people and animals. The operator should release the pressure safely using the control box levers and then remove the hose in a place where it can be safely uncoupled from the end. From here, the operator should pull back sufficient hose length for safe uncoupling of the damaged hose and the inserting of a new one, taking care not to damage the coupling on the end of the hose. The damaged hose end should be directly connected to the new hose, ensuring that the “point of failure” is not reached when pressure is applied. Then and only then should the pump operator re-pressurize the air line and allow the coupled hoses to shift. A better method, however, involves not having the until the next man is present to dig the hose out!

Positioning of Pump – Always try to plan and position the pump so it can assist in the event of a concrete related emergency, i.e. blowing lines for blockage. This also applies if you need to get closer to a building etc. Pump should always reverse into site ready for quick and easy exit in case of an emergency.

Know your site; in the event of an emergency, the ambulance service must be able to find you. Emergency Services Contact – Make sure to have a list of emergency contact telephone numbers clearly displayed on the pump.

When things go wrong, prompt and effective action can help reduce the severity of accidents and injuries. Workers also need to know how to protect the casualty, but only attempt treatment if trained to do so. The following procedures are in line with regulations and general good practice. Concrete pumping is safer with an adequately trained and safety conscious workforce.

3. Equipment Familiarization

The Piston Rock is a valve system used to control the flow of concrete in an environment of low output and/or when pumping with high abrasion materials. The pistons are usually made from polyurethane material, with tungsten or steel pistons being used for pumping more abrasive mixes. A hydraulic circuit drives the Rock Valve, allowing the pump to have no other wearing parts. This model of concrete pump can generate no pulsation, allowing for a more controllable flow of concrete. This type of pump is capable of handling aggregate sizes up to 40 mm and performs well in low to high output applications.

In complex or high-rise buildings, and when a distance of over 100-150 meters needs to be pumped with concrete, the maintenance cost for the entire operation can be reduced by using a truck-mounted pump. Hence, a truck-mounted pump is the best choice for the majority of operators. Concrete pump spare parts available for this type of concrete pump include ram/cylinder kits, seal kits, spectacle wear plates, slew shaft pins and bushings, concrete pump pipelines, and an elbow.

The truck-mounted concrete pump is a logical extension of concrete pump technology. It is designed specifically for users who have been used to a truck mixer/straight concrete pump combination. A truck-mounted boom pump offers the flexibility to pump directly with a truck mixer and can also be moved to a job site where a trailer pump is not possible.

3.1. Components of a Truck Mounted Boom Concrete Pump

The general layout of a truck mounted boom pump is similar in many respects to a mobile pump. The simple design makes operation and maintenance easy. Essentially, the machine can be divided into three main areas: the chassis, the pumping system, and the boom. Each of these areas requires a different level of qualification and skills to operate and maintain, and this is reflected in the competency assessment for this unit.

A truck mounted boom pump uses a remote-controlled articulating robotic arm (boom) to place concrete with pinpoint accuracy. Boom pumps are usually used on large construction projects because of their ability to pump large volumes of concrete. They have a range of 20 – 60 meters. It is more time efficient to use this machine than other methods due to the ease in which the concrete can be pumped to the location. This is particularly beneficial to projects where other methods of concrete placing, such as wheelbarrowing, are not feasible due to time, distance, or access restrictions.

3.2. Controls and Functions

The main input device for any hydraulic system is the hydraulic control valve. This is merely a spool valve in a housing that will direct oil flow to the actuators to perform work. The direction that the spool is positioned will dictate the direction of the oil flow and therefore the direction of the actuator it is controlling. Movement of the spool can be done manually, mechanically or hydraulically. The valve in figure 11 is a 6 port 3 position spool valve in central neutral position. This is represented by the “O” in the centre. This valve can move to left working position or right working position, and the oil will only flow in the direction selected. A 6 port 4 position valve could have, for example, a regen position in which the flow will go to the rod end of an actuator and then, upon return to neutral position, the oil will flow to the blind end of the actuator. This type of valve would commonly be used in ground working equipment. Perhaps the most simple of control systems is the open centre system. This is where the pump will flow oil from the tank to the directional control valves and then to the actuator. The valves govern the direction of the oil flow to and from the actuator. When the boss on the control lever is pressed, the valve will allow oil flow to the actuator. When released, the flow of oil will stop. Movement of the valve will alternate the direction of the flow of oil to the actuator and therefore obviously alternate the actuator direction. This type of system only provides full and smooth/slow actuator speed, usually not satisfying the requirements for modern machinery.

3.3. Maintenance and Troubleshooting

Every contractor and owner of concrete pumping equipment has, at some time, experienced a material blockage in their line. No matter what kind of pump is being used, it cannot continue to keep concrete in a flowing state indefinitely. Understanding why blockages occur and the proper techniques that should be used to clear them can save a large amount of time and frustration.

Consulting with a licensed mechanic experienced with heavy equipment operation is always a good practice. However, if a problem with the equipment is suspected to be the cause of faulty operation or performance, the representative from the manufacturer should be contacted. Be ready to provide the model and serial number of the machine as well as the component in question.

A maintenance log should be kept on the equipment to help identify any wear to components. Once identified, that component can be scheduled for replacement before failure and downtime. Each manufacturer will provide a list of scheduled maintenance items or a maintenance chart which should be followed. Both safety and performance are enhanced while the cost of ownership is minimized when the maintenance program is followed. Keep the equipment as clean as possible. Excessive build up of concrete material and or the spillage of grease and oil can create a hazardous work environment. When working with waterblasting equipment to clean the machine, be aware that the high pressure can damage hydraulic components.

4. Setting Up the Pump

Site assessment and preparation – This is a very important step in setting up the pump. Whether using a trailer-mounted pump or an excavator to move the material to the pump, site assessment and preparation is very important. The key is to create efficient access and enough working room around the pump. This will save time and effort in the long run. Site conditions vary in many ways. Ground conditions can be soft, wet, or uneven and at times not suitable for equipment due to incorrect type of material being laid over and drainage slope. Ground conditions should be assessed for suitable bearing strength to ensure the machine you are using will not sink or become unstable while in operation. It’s advised that ground conditions should be at least 70% of the machine’s overall weight. If ground conditions are in question, advice should be sought from an appropriate individual from within the civil engineering and construction industry. Excavator and trailer-based pumps should be positioned as close to the area as possible to minimize hose length. This will save time in moving material to the pump and handling pumped material. Ensure that access to the hopper and the rear of the pump is clear for material to be moved and the hose to be laid. An ideal situation would be to park the unit and not have to move it until the job is complete and it’s ready to be loaded back onto the truck for transport. The machine should be positioned on a firm and even base. If this is not practical due to poor ground conditions, the tracks or wheels can be placed on suitable sized timber mats to alleviate machine movement and slope. These should be at least 300mm longer and wider than the tracks or wheels.

4.1. Site Assessment and Preparation

Is the base and subbase compact, concrete, and strong? The pump is extremely heavy and fully loaded outriggers can exert a force of over 22 N/m2 (approx 3.5 tons per square foot). The pressure from the outriggers may cause piercing or rutting, relative movement of the subbase or base, pocketing of subbase material, and sinking, the climb/slide of the base and form movement. In layman’s terms, if you do not prepare the area beneath the pump to cope with the weight and pressures, the pump may not be able to carry out its operation and in some cases, the pump may become stuck in place. This will create considerable frustration for the pumper and contractor along with expensive restoration costs. Stabilizing material can be placed under the subbase to prevent pump sinkage. This will increase the strength and stability of soft soils or fill. If assessors are not sure the subbase has the necessary load-bearing capabilities and/or compaction, it may be necessary to carry out tests with a qualified structural engineer. The visual look at the subbase may be deceptive (subbase material may be good but has insufficient compaction), and a structural engineer can evaluate possible future remedies and advise on suitable locations to set up.

The first activity for setting up the pump is for the pump operator to carry out a control measures HIRA with the contractor. This will enable any potential hazards identified to be eliminated or controlled to prevent the risk of incident or injury. (Remember to take into account the delivery driver if he is from another company). This may also be a requirement for Method Statements and Risk Assessments to be carried out, the location of these documents and the knowledge of the site manager. There are numerous sub activities that need to be looked at when site assessing and preparing.

4.2. Stabilizing the Truck

Jacks should be vertical with the load spreader centered to avoid any twisting effect. Uneven or loose ground is always a problem on site, timber mats are ideal to increase the base area of the jack. If these are unavailable then additional support with steel plates should be used. If the ground is still too soft, the outrigger can be supported on a square of shuttering ply, which must then be nailed to the ply underneath to avoid it slipping. The load spreader should be fixed by bolting or welding to the shuttering ply depending on the equipment being used. From time to time the jacks may need readjustment, it is important to monitor this as failure to do so may damage the jacks, overload them and/or cause them to sink into the ground. If jacking off the mudsill of the truck it is necessary to ensure it is level and proper preparation is in place to avoid slipping. When constructing a levee it is important that the bank angle does not exceed 45 degrees. Failure to ensure this may cause the silt to give way and thus the levee collapses, often sinking the outrigger in the process. A similar problem occurs in cindered areas; it may be necessary to tile or shutter on these surfaces to increase the friction between the levee and the ground.

4.3. Extending and Positioning the Boom

The modern boom type concrete pump is usually comprised of a truck that has the pump and frame, and a typical placing boom of three to six sections in length, to a total of 200-220 feet (61-67m). At the beginning, it is important to familiarize the location of the placing area in relation to the truck and to plan the desired path of concrete delivery. Avoid working on slopes when possible. It may be necessary to inspect the job site to ensure that it is level and firm enough to support the weight of the truck and the boom in all positions required to place concrete. A site inspection should also identify possible safety hazards, such as utility lines or areas where excavation might weaken the ground. Do not use the pump where ground is too soft or likely to be undermined. Availability of a good setup area has to be balanced against the desired location of the placing area and the reach capabilities of the boom. A job requiring boom with a long reach, and pinpoint placement in tight spots would be conducive to the use of a separate placing boom of the roll and placement or one attached to the building with a stationary pump. Before starting to pump concrete, the pump operator should have already been informed of the placement company’s safety policy. Pumps and booms are designed to be safe, and job site accidents involving pumps are usually a result of not taking the time to think about safety. A good operator with awareness and foresight about the operation of the pump and the movements of the placing crew will be able to keep everyone safe. Keep all workers and other personnel not involved with concrete placement at least ten feet away from any part of the equipment while priming, or discharging concrete. All personnel involved with the pump and placement should know the location of the emergency stop button on the radio remote control and the location of outrigger safety hold-down straps.

5. Pumping Operations

Pumping concrete is a tough job and accidents occur too often. In the event of a job-site accident, it might be that a quicker setting mix is needed to stop the cure of concrete in the wrong place. Familiarize yourself with the mix design report form and be prepared to answer specific questions about the mix in the forms provided in the ACI Manual of Concrete Practice section 3.2.2. This section should be completed between the pump operator and the persons responsible for the mix.

Concrete mix designs are often made to suit the purpose of the pump so that it can push the concrete through with the least amount of resistance. The mix design depends on the type of pump being used, stationary/mounted or line pump. The usual ratio is 1 part water, 2 parts fine aggregate, and 4 parts coarse aggregate. This should create an easy-to-pump formula for the operator. Mix designs can be investigated further in Michael W. Rosato’s (Published 1997) ‘Construction of Concrete Pavements’ starting on page 236.

5.1. Concrete Mix Design and Pump Selection

The second type of concrete mix design is designed specifically for use with a concrete gun. These tropical mixes are usually of high moisture content and are more fluid than other mix types. Although, like line mixes, they have a high gel and silt density. This mix type is designed for spraying at high velocity and depth onto large surface areas. The end product is a smooth finish with little air pockets.

As the channel through which it is pumped is subjected to significant amounts of wear, it is important that the concrete has sufficient durability and a relatively low moisture content. Having a high gel silt density will also help to prevent the concrete from separating from the water and has the added advantage of making the concrete easier to clean in the event of a blockage.

Line pumping is the most common method of pumping concrete. This requires a relatively harsh mix to ensure sufficient strength. Usually, more cement is used than in a traditional mix, enabling the concrete to achieve a high gel and silt density. A slump of between 8-12cm is also required.

When pumping concrete, mix design and pump selection are important parts of the project. Generally, there are three types of concrete mixes designed for pumping applications.

5.2. Pumping Techniques and Best Practices

– A level base of support is required for both the concrete pour and the concrete pumping equipment. This is particularly important in vertical pumping. A sloping base can lead to slippage of the concrete mix or the pump itself. The latter can have serious safety implications. A secure and level base will also aid the stability and alignment of the concrete pump.

– It is always good practice to keep pipe runs as short and as straight as possible, and ideally loop around with a 5m minimum radius. This will reduce the number of bends and minimize pipe friction, which in turn reduces concrete pumping pressure. Looping around will also allow the concrete to flow back and self-level if the pour is interrupted.

– Where it is possible, concrete should be placed to facilitate downhill or horizontal pumping. Upward pumping is less effective, more time-consuming, and requires greater effort in terms of concrete pumping pressure. That said, with the advent of specialist concrete pumping equipment, there are very few situations in which concrete cannot be placed.

– Concrete should be poured as close to its final position as possible. This is particularly important in floor slab construction. The closer the concrete is to its final position, the better the chance of obtaining a good surface finish. Close pouring also minimizes the impact of concrete free-fall. Reducing the height of free-fall will help to alleviate segregation of the concrete mix.

There are a number of key criteria that should be observed when concreting, and these vary from job to job. The following is a list of the most common:

5.3. Dealing with Blockages

If increasing the pump pressure does not clear the blockage, the next step is to shut the pump off and release the pressure from the system. ENSURE THIS IS DONE SAFELY. Once pressure is released, remove the end hose and/or reduce the size of the line using the reducer, and then use a rubber/plastic mallet to hit the hose coupling. The excessive force will clear most blockages. If the blockage cannot be cleared on the hose, the next step is to remove the elbow from the end of the affected section, and if required, work your way back up the line removing hoses and using the mallet technique to clear trapped concrete. This should clear 90% of blockages.

The first point of action when a blockage occurs is to stop the concrete supply and let the pump continue to operate. This should dislodge the blockage in the line in a short period of time. If this does not work, cautiously increase the pump pressure setting to a maximum of 100 bar. This should be sufficient to clear any blockages in the boom.

Blockages often occur in the boom and lines. The cause of blockages can be one of several things: pipe/line blockage, rock jams in the intake system, or the accumulation of concrete in the hopper.

6. Cleaning and Maintenance

Off-hire the machine for cleaning when there will be a delay until the next pour. After the last pour, it should be washed out at the end site in a designated area where wash water can be contained and disposed of in accordance with environmental protection legislation. When washing out at the end site, the concrete should be allowed to run out to a manageable state, i.e. when the drum stops turning, add water and allow the slump to increase so that the concrete becomes more flowable but still able to be pumped. The pump should then be started and the concrete pumped for a short time. Add water to the hopper to clean out the remaining concrete. Alternative method for line cleaning: If there is a requirement to move to a different jobsite, an efficient method of line cleaning is to introduce a cement/water slurry into the system and then pump through another line sponge into a receptacle to be disposed of in the same manner as the wash out from the hopper.

6.1. Post-Operational Cleaning

c) It is essential that the material left in the rams and pistons has been pumped out. Disconnect the delivery hoses from the cylinder to the accumulator. This will allow the accumulation of all residue left in the delivery hose cylinders to be effectively reversed back down the hoses.

b) When the machine has completed pumping and the material in the hopper has been completely pumped through the machine, the pumping pistons should be in the retracted position, and while still switched on, the hydraulically powered rams should be cycled to the end of their stroke and back a number of times. This will effectively disperse and pump out the remaining water and concrete in the rams and will help to prevent concrete setting on the rams, which can damage the seals and rams themselves.

a) When pumping has finished, the pump and pipeline should be emptied of all concrete in the most effective way. The sequence of position for the pipeline to drain out as much material as possible should be determined prior to pumping out. If there has been material segregation, it may be necessary to return this to an acceptable state of consistency to enable effective cleaning of the system.

This subject is very varied and dependent on the type of concrete and the consistency. Generally, the system should be left to free flow until the material has completely cleared the system. The size of the pipeline and diameter, length of the system, and the type of concrete will all affect the time required to clear the system. If the system becomes blocked during this process, it should be noted what the blockage consisted of and how it was cleared. This will signify if the material used was too harsh or unsuitable for the system in question.

6.2. Regular Maintenance Schedule

6.2.2. Hydraulic System Hydraulic oil temperature is the most important factor to consider during the hot summer months. Above 80°C, oil life is dramatically shortened and every 6°C over this will halve the life of the oil. This is also dependent on the amount of water content in the oil. Oil should appear on the dipstick between the Min and Max marks, and every 500 hours, the tank should be drained and refilled with fresh oil. An oil analysis of the sample will give a good indication of whether the 500-hour period can be reduced. An inline hydraulic oil filter will remove most particle contaminants and give longer component life. Clean hydraulic oil is 75% of component life.

6.2.1. External Cleaning After returning to the job site, clean the fins of the cooler by flushing with water. Regular washing with low-pressure water and a stiff brush will reduce the possibility of airborne dirt and dust being drawn into the hydraulic system. Pay particular attention to the hydraulic oil cooler and the engine air cleaner. These items need a clean and cool environment to give maximum service life.

Small, regular care can often prevent breakdowns and downtime and can reduce repair costs. The pump unit is a small investment in relation to the total cost of a concrete placing job, but it is the heart of any placing system and must produce profit by pumping the concrete. A well-maintained unit will give a longer economical service life. A daily walk-around visual inspection should be carried out. This should be repeated after the first hour of pumping and then at two-hourly intervals. A maintenance chart is given at the end of this section.

6.3. Common Issues and Troubleshooting

Foreign objects entering the system – This acts as one of the most common problems faced. As the concrete is in a liquid state, and with the system being primarily open at the hopper, dirt, concrete splatter or other such material can enter the system and this may cause blockages to the system. It is important therefore to try and keep the area around the hopper as clean as possible and to use the correct lid to cover the hopper if the unit is not being used for an extended period. Blockages are usually noticed by a loss of pressure at either the concrete pumping cylinders or the hydraulically operated ones. The pressure can be measured using the pressure gauge usually located on the control panel. A loss of pressure at the pumping cylinders probably indicates a blockage somewhere in the concrete part of the system and a loss of pressure at the hydraulically operated cylinders indicates a blockage in the S valve operation part of the system. Blockages are sometimes cleared by reversing the flow of concrete back to the hopper, however, this is not always possible and other means may be necessary. If it is suspected that a foreign object has entered the hydraulically operated part of the system, it is best to remove the S tubes and operate the system to try and clear the object. This is to prevent damage being caused to the S valve, as this unit is very expensive to repair or replace. An easy but effective prevention of blockage to the S valve area is to keep the machine on a slope with the hopper being at the higher end, as this will prevent any material running down from the S tube connections.

7. Final Assessment

Afterwards, the candidate will undergo the final assessment and will be divided into 2 parts. One being the written examination, and another being the practical evaluation. During the written examination, the candidate will have to answer 55 multiple-choice questions within 1 ¼ hours. This will be done under closed book conditions. The candidate must achieve at least 80% to pass. The practical evaluation is a continuing assessment throughout the remaining course. The examiner must make sure that the candidate has met all the learning outcomes and has demonstrated having completed the relevant NVQ units. If the candidate has not met all the requirements in the practical assessment, then the candidate will be required to take a CPCS renewal test after the expiry date of his red trained operator card.

7.1. Written Examination

All candidates must pass a CSCS health safety and environment test and touch screen test within two years of completion of the theory session. Candidates who fail to do so may not apply for the issue of their card until such time as the necessary tests have been passed. This is an industry requirement for all competent operator cards. The CPCS Theory Test is designed to determine the candidate’s overall knowledge on theory and principles of operation of the machine type. There is a general test paper which covers knowledge common to all types of plant, and a further test paper specific to this plant type. The theory knowledge test pass mark is a minimum of 80%. Failure to achieve this will result in referral back to the employer. A theory knowledge test pass is valid for two years. Candidates who already hold a CPCS Red card with theory pass for the machine type being tested will not be required to re-sit the theory knowledge test. Finally, the CPCS Plant card multiple-choice theory test paper is valid for two years. If a candidate already holds a theory test pass within 2 years but has failed theory questions on the written paper for the machine type they are now being tested on, the candidate will not be required to re-sit the theory knowledge test again but must book a theory knowledge test question paper and pass. Written answers to theory test questions are only valid if the candidate has a theory knowledge test pass within the same two-year period.

7.2. Practical Evaluation

10. The trainee will carry out the actual concrete pour using both the long and short rigs with guidance and instruction from the instructor. This is to ensure that concrete placing techniques are carried out correctly and the trainee can ensure that concrete is being placed in its defined area. The instructor is looking for an overall confidence using the controls and smooth coordinated operation between the unit and placing crew.

9. The trainee must provide the instructor with an overall system safety assessment and discuss risk and hazard aspects and how they are minimized. For example, hose handling/movement and manual handling of the end hose. It may be necessary for work in close proximity with others (other trades) in which case the trainee will interact and inform those concerned of the relevant safe working exclusion zone around the placing boom structure. Under supervision, the trainee will demonstrate a complete set up and preparation of the unit for the particular job and the instructor will assess the methods used and look for any areas of improvement. Future service and inspection work will be discussed to ensure that the type of work is not just a one-off on the training day.

8. For the purpose of practical evaluation, the trainee will prepare for the long and short rigs, the latter incorporated as part of the boom structure, for different types of pours fundamentally in architectural, schematic or method designs. Typical pours would be a large mass fill on one level where the pump can be set up centrally to the work area or a series of pours with the unit remaining in the same set up position but having to adapt to changes in the work area level due to access and egress by the building operatives.

8. Certification and Continuing Education

Section 7 was devoted to training and developing operator skills. The certification process is the next step in a solid operator development plan; the industry requirement is the CPCS (Construction Plant Competence Scheme) applicable categories need what is known as a blue card (Trained Operator). The CPCS scheme allows operators to demonstrate their ability, expertise, and knowledge to a level that is nationally recognized. CPCS is largely based on NVQ (National Vocational Qualification), and operators will be expected to compile a portfolio of on the job evidence, some of which can be done in the operator’s own time and without their employer’s knowledge. In order to get the required evidence, operators will be continuously assessed over a period of several weeks or even months. This process can be time-consuming, so adopting NVQ key skills in literacy and numeracy is a good idea, as portfolio and evidence compilation tends to involve a lot of writing. On category achievement, the operator can apply for a ‘red trained operator card’, at this point an NVQ in plant operations is highly recommended for those who have not previously obtained one through the portfolio route for permit and competence schemes are increasing in cost and operators will find it difficult to gain site access. Previous blue card requirement was to retake the theory/practical test within 2 years of sitting the competent operator course. This was not enforced and resultantly has led to confusion about the card life and renewals. Blue cards are now valid for 5 years, although there is no formal assessment the operator can at any time apply for the NVQ and blue card upgrade to the now equivalent requirement, or take the next step to the competent operator tests. Note: both progression routes will involve card upgrade to confirm category competence, click subscription then LFPlant news for the March 2009 newsletter discussing this.

8.1. CPCS Certification Process

The test centre will then apply online with the details of the operator and the card being applied for. Online applications can be made by registering with the CITB and logging into the construction equipment application system (CEA). This system will automatically request the CITB health, safety, and environment test results from the info construction database. Any applications received by post will not be accepted, and a return will be requested using the correct method.

The accredited test centre will carry out an applicant check with the National Plant Operators Registration Scheme (NPORS). If the test centre is not already an NPORS centre, they are required to make an applicant check with NPORS. It must be ensured that the applicant has a valid logbook.

CPCS certification is required for all plant operators. Certification proves that the plant operator is competent and qualified, and is essential for advancing in a plant operator career. The trained plant operator should contact an accredited CPCS test centre. The operator is required to provide evidence of identity, training/achievement, and CITB health, safety, and environment test (or accepted exemption) within the 2 years prior to the CPCS technical tests.

8.2. Continuing Education Opportunities

Further to the higher management qualifications, one may undertake a career as a lecturer or train NVQ candidates in construction supervision and management. This would only be viable for someone who is dedicated to knowledge and training, and most lecturers will hold a degree qualification in their teaching subject.

Continuing from the NVQ level 3 diploma, an experienced and competent supervisor will be now contemplating a role as a Contracts Manager. In most construction sectors, a contracts manager is pivotal to the success of a job and has a higher level of responsibility than that of a site supervisor or agent. An aspiring Contracts manager has an onward path which leads to the achievement of an NVQ level 6 or 7 in Construction Management. This high standard qualification provides the knowledge and skill set to work at a senior management level and will open new doors to management positions and contracts management with main contractors and specialists. In the public sector, it is obligatory for managers to have an NVQ level 4 or higher, and the deadline for this is September 2017.

This qualification will ensure that a CPCS card holder has transferrable knowledge based on operative methods to supervisory/managerial roles. A supervisor/manager holding the level 3 diploma will be capable of applying and implementing work methods whilst conducting activities, to safely and productively supervise a team. This could include method statements, resource allocation, work progress, and potential obstacles. The knowledge obtained by a level 3 diploma holder is highly relevant to specialized roles within the construction industry, and collection of data shows that there is a high percentage of level 3 diploma holders within the concrete pumping, steel fixing, and formwork sectors.

Continuing education is critical to a structural operator or worker as it ensures they are kept up-to-date with the latest methods, operatory techniques, and disciplinary changes. In following, a person certified with a blue CPCS card for the truck-mounted concrete pump will be required to complete an NVQ level 3 diploma in occupational work supervision within 2 years of their certification. This qualification is a natural progression for someone who already holds a level 2 qualification in various roles within the construction sector.