Machines and Equipment
Barrel Bore Grinding Machines Screw Milling Machines Shaft Milling Machines
Horizontal Milling Machines CNC Vertical grinding machine Surface Grinding Machines
Steel cutting machines Lathe Turning Machines Drilling Machines Milling Machines
Grinding Machines Barrel Deep-Hole Boring and Honing Machines Straightening Machines
CNC Machining Facilities, including mills and lathes Welding Machines (PTA, etc.)
Polishing Machines Nitriding Furnaces Barrel Centrifugal Casting Equipment
Manufacturing Expertise
Most screws are manufactured from high quality 38CrMoAlA( SCM645 in JIS ) steel which is a chromium-aluminium-molybdenum nitriding steel. Nitriding is a heat treating process that diffuses nitrogen into the surface of the screw, to produce a hard surface on the component. Depending on the size of the screw either a gas or plasma nitride process is used to give an even depth of hardness across the screw profile. After Nitriding, a minimum surface hardness of 950 Vickers (VPN), equivalent to 68 Rockwell is achieved with a hardness a depth of between 0.4 – 0.6 mm. Nitrided screws provide a good general purpose component that can be refurbished to standard at a later date.
For more demanding high wear or corrosion applications, in addition to the normal nitriding process, screws can be supplied with additional surface treatments including hard facing on the flight lands or coated to provide the optimum resistance. Hemu Precision offers a number of hard facings applied through Plasma Transferred Arc (PTA), Tungsten Inert Gas (TIG) welding processes and HVOF thermal spray coating..
Weld applied Hard facing grades include:
Nickel-Base Hard-Surfacing Alloy with Chromium Boride(CrB2)
Cobalt- Base Hard-surfacing Alloy
Further coatings can be provided including:
HCP (Hard Chrome Plating)
Fe-based Alloy Inlays
Stainless Steel inlays
Tungsten Carbide
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