Plasma welding is used where narrow welds are needed and where attention is focused on thermal distortion and welding speed, hence this machine was designed for the specific use in the rebuilding of worn crests on old screws or the hard facing inlay of new ones.
Plasma ionized gas at very high temperatures (30,000 C) is used and is generated by sending a jet of gas through an electric arc.
MACHINE SPECIFICATIONS
 The main bed is Electro- welded steel in construction and is fitted with four high precision INA roller guideways with four sliders which supports the carriage. Also two INA ball guideways with sliders to support the tailstock.
The carriage movement is obtained by rack and pinion and driven through a Holroyd reducer and a Siemens axis motor. The rack is precision ground and is of Mod 4.
The headstock is formed in cast iron and encases the steel spindle which is supported by two "TIMKEN" bearings. The spindle nose is of ASA 8" type and is rotated directly by a Holroyd reduction worm gear and coupled by a Siemens motor with 15 Nm torque.
The tailstock is manually positioned on the bed and locked when in position. It runs on precision guideways located to the front of the bed. The tailstock quill is 120 mm in diameter. The tailstock nose is Morse 5 type and is moved by hydraulic piston.
WELDING SPECIFICATIONS
TORCH and HIT CONTROL SYSTEM
Type P.T.A. 330 with independent Cooled Control Panel with PLC OMRON CQM1 with:
Digital fluxometers with regulation potentiometer and reading display of three gas rate flow
Universal scart for external speech test gas
Gas di riferimento
Start/stop pilot arc
Open arc device for movement
Alarm and emergency stop LED’s
Mini-inverter OMRON mod 3G3 for the starting of powder motor with regulation potentiometer and reading display
Water temperature controller with reading display
Voltage display
Inverter power generator for a tri-phase pilot arc 160A limited 75A with HF discharged device separated and potentiated
Transferred arc tri-phase inverter power generator 420A limited 200A with Man-Auto switch and display of set out amperage
Cooler 5250W powered with safety devices for water circulation for the torch cooling
P.T.A. YZR 250 torch standard plasma nozzle, nozzle for gas, laser pointer and kit spare parts
Powder feeder mod AS97 with powder pre-heater and overturn device
Interface robot R2 for signaling control
Powder Koy 51 P.
HMSP 2-37 is the most generally useful cobalt alloy having excellent resistance to many forms of mechanical and chemical degradation over a wide temperature range. Particular attributes are its outstanding self-mated anti-galling properties, high temperature hardness and high resistance to cavitation erosion and corrosion.
- Typical chemical analysis C 1.1%, Si 1.0%, Cr 28.5%, W 4.2%, Co Bal.
- Sieve range ([ m): 150-53
- Melting range °C : 1825 – 1375
- Typical hardness on cast material (HV 30) : 480 (44 HRC)
- Coefficient of thermal expansion (10-6 /°C) : 15 (20-800°C)
- Hall flow approx. (sec/50g): 15.8
- Apparent density approx. (g/cm³) : 4.4
- Specific gravity (g/cm³): 8.5
- Wear: Threshold galling stress (kg/mm²) on a 1020 steel block: W 25
- Weld (two layer deposits on 0.2%C steel)
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Temperature °C
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Hot hardness (as welded)
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20
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480 HV30
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250
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410 HV5
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500
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310 HV5
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700
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260 HV5
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