|Small Plant Machinery|
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.
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.
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.
If 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:
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 the engine to storage, ready for the next exercise.
In 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.
When dealing with water pumps, there are three main terms we use: