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Glossary of terms you will come across during your Phase 2 training.

Small Plant Machinery


Cement mixerCement Mixers, or Concrete Mixers are common items of small plant that cp fitters will find themselves working on from time to time.

Mixers can be electrically powered, or come with diesel or petrol engines.

In the small plant module, there is a learning unit dedicated to concrete or cement mixers.


Typical consawAbbreviation for concrete cutting saw, also referred to as a cut off saw. Consaws are one of the learning units of the Small Plant Module.

Stihl - Cut-Off Machine Safety, Maintenance and Operation Video


When water is pumped up to a height, that height is known as 'delivery head'. The more powerful your engine is, the higher you can pump the water to.

  • Exciter shaft from the Bomag plate compactorEccentric means off-centre
  • Mass is a measure of the amount of matter in a body. It is measured in kg.
  • Eccentric Mass is an off-centre mass

Eccentric masses are used in plant machinery whenever we want to produce out-of-balance forces such as those in vibrating machinery - the Bomag Plate Compactor (the exciter shaft), the Bomag double-drum roller or in vibrating pokers.

The image on the right here is of the exciter shaft from a Bomag Plate Compactor.

There are massive out-of-balance forces produced by these shafts when they are driven at speed. This sets up massive radial loads on shaft which must be supported by bearings. There are no axial loads on the shafts and bearings, only radial loads, and for this reason, it is mostly ball bearings and roller bearings which are used to support these shafts.


Heat discolouration on a chainsawIf a component gets too hot, this heat will discolour the metal in that component.

By carefully observing the different colours, you can even tell how hot the metal got.

Colous range from a light yellow to dark blue.

In the example shown here, there was a problem with the lubrication for the chain on this chainsaw, causing it to overheat. During routine servicing and inspection, this discolouration was spotted, and the chain lubrication system was adjusted to provide sufficient lubrication for the chain in operation.

Below, we can see the connecting rod and crankshaft assembly from a 2-stroke engine. This assembly overheated, and there is clear evidence of this in the discolouration toward the big end of the connecting rod:

Heat disclouration on a connecting rod from a 2-stroke engine.

Contributors to this web page: Fergal Weldon (Navan Hire and Hardware Ltd.) and Cian O'Brien (O'Brien Tool and Hire Ltd.), CP Fitters, July to November, 2012.


Apprentices engaged in the Lifan 5 HP Engine ExerciseOn the Phase 2 course, there are 6 modules, and each module is further sub-divided into 6 or 7 learning units. Each learning unit has one or more suggested exercises.

During the Small Plant Module, each apprentice takes part in the Lifan 5 HP Engine Exercise. During this exercise, apprentices completely disassemble a fully serviceable 5 HP, 4-stroke, petrol engine.

They lay out the parts, and compile a list of the name and function of each piece. They also study the carburettor  and the ignition system on the engine. In addition, they study the speed governor system.

When they have done this, they reassemble the engine, mount it on a stand in a bench vice, and run the engine to verify that it is operating correctly.

When they have verified the serviceability of the engine, they fit a service lable on which they outline the work they have carried out on the engine. They then sign the lable and return the engine to storage, ready for the next exercise.


Maco air compressorIn the context of small plant machinery, this refers to a machine that delivers something, only when the operator demands it.

For example, an air compressor will run at idle and will not supply compressed air until the operator uses a pneumatic tool attached to that machine. As soon as this happens, the engine on the air compressor speeds up and the compressor delivers the compressed air necessary. This last only as long as the operator demands the compressed air.


Suction liftWhen dealing with water pumps, there are three main terms we use:

  1. Suction Lift
  2. Delivery Head
  3. Total Head

  1. Suction Lift is the height which the water pump lifts the water up from. It is more accurate to say that the atmosphere pushes this water up the delivery hose.
    Because the force exerted by the atmosphere is finite, pumps can only draw water up a maximum of approximately 10 metres. The atmosphere cannot support a column of water any higher.
  2. Delivery head is the height up to which the water is to be pumped. This is only limited by the power of the water pump.
  3. The total lift is the suction lift plus the delivery head.


Please note, if you want to contact the main Training Centre in Baldoyle, you need to ring 01-8167400.

If you want to contact the CP Fitters' Section, you can Contact Us by email,, or by telephone: 00 353 1 8167543 This number gets you through to the CP Fitters' Section, Baldoyle Satellite Unit.

Our Address is : Construction Plant Fitters' Section, Unit 116, Grange Way, Baldoyle Industrial Estate, Baldoyle, Dublin D13 CA48.
We operate in a satellite unit which is about 300 metres away from the main training centre. You can see the location of this unit here, in Google Maps. You can also Check here for directions to the Baldoyle Training Centre.

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