Charpy Specimen Milling Machine – CNM is designed to enable laboratory personnel to produce their own Charpy test samples instead of waiting for machine shop time. It will produce 10mm square Charpy test specimens from rough cut samples of up to 15mm square.
Two variations of the Charpy Specimen Milling Machine (CNM) are available to cover a wide range of materials.
The Fixed Speed Machine is recommended for customers who are producing specimens in carbon steels, easily machined low alloy steels, non-ferrous and plastic materials.
This machine has a fixed cutter speed of 1.98 m/sec(50Hz), 2.38m/sec(60Hz) and a variable feed rate for the samples of 2.5-9.0 mm/sec.
The Variable Speed Machine is recommended for customers who are producing specimens in carbon steels, more difficult to machine alloy steels, stainless steels, non-ferrous and plastic materials.
This machine has a variable cutter speed of 1.0-2.5 m/sec and a variable feed rate for the samples of 2.2-9.0 mm/sec. The varying of the cutter speed for differing materials improves the cutter tip life.
The machines are of robust design and construction, enabling them to produce specimens to the surface finish and tolerances required by International Standards.
Both machines are designed for mounting onto a customer’s bench and are fitted with an easily removable swarf (cuttings) tray.
The cutting process is carried out without cutting fluids. A fully encapsulating removable cover allows ready access to the motor and drives for periodic maintenance.
The circular fixture allows up to four specimens to be machined during the same operation.
Various clamps, anvils and clamping screws are available to suit the type of rough cut blanks being used.
One circular fixture is included with each machine. For maximum machine production, a 2nd fixture (optional extra) is recommended, so that whilst the 1st fixture is being machined, the 2nd fixture can have its samples loaded.
The cutter is fitted with five ISO carbide inserts, which are easily replaceable.
A micro adjuster allows for accurate control of specimen size and allows for compensation of cutter tip wear.
The rotating work holding fixture is fitted with clamps, anvils and clamping screws to suit the type of blank being used, i.e. rough sawn square/rectangular, round or tubular section and the size of the specimen to be produced, i.e. 10mm square or sub-size.
For ease of fitting samples, the fixture is removed from the machine and placed onto a bench mounted holding bracket, one bracket is supplied with each fixture.
Up to four rough cut samples may be loaded into the fixture, which is then re-mounted onto the machine spindle and the cutting cycle started.
The machine cuts the first side of the samples(1st cut).
The fixture is then removed from the machine, turned through 180 degrees and refitted to cut the second side of the samples (2nd cut).
After completion of the 2nd cut, the fixture is removed from the machine and placed onto the bench mounted holding bracket.
The samples are removed and remounted into the fixture at 90 degrees. The fixture is then mounted into the machine to cut the third side (3rd cut). The fixture is then rotated to cut the fourth side (4th cut), which completes the production of the 10mm square samples.
Adjustment of the micro-adjuster may be necessary to achieve the required size and dimensional accuracy of the finish machined
Fixed Speed Machine, 900 x 500 x 650 mm
Variable Speed Machine, 900 x 500 x 715 mm
Weight: 210 Kg
380 or 415 or 440 Vac (customer to advise their voltage for setting at our works)
3 phase, 50/60 Hz, 4 KVA
480 Vac optional