WHY A CUTTER WITH TUNGSTEN CARBIDE TIP IN THIS AGE OF CERAMICS? |
To help you see the reason, let us make a few remarks concerning a shutter cutter on the market. Cutting is possible principly with those two blades moving vertically and parallely, allowing no clearance between them. But the fact is the two blades cross each other in actual cutting movement, and while crossing, they repeat contact somewhere at one point. That contact possesses a problem with a ceramic cutter. Ceramic is quite fine and may be used for life where only line contact of the blades is concerned. But that is not the case with point contact. Here, brittle nature of the ceramic comes into light that causes "chipping" of the blade. The tungsten carbide tip is made up of tungsten, carbide and cobalt. It is used for the cutters of Toyoda AJL, Tsudakoma AJL, Rapier Looms, Air Jet Looms and Water Jet Looms in various countries. The following is a chart of durability comparison of tungsten carbide vs ceramic in particular respect to achievable operating frequencies. |
MC Shutter Cutter (ceramic) |
Air Jet Loom Selvedge Cutter (Tungsten Carbide |
||
Service time | Frequency | Service time | Frequency |
1 min. | 3 | 1 min. | 600 |
1 hr | 180 | 1 hr | 36,000 |
1 day (24 hrs) | 4,320 | 1 day (24 hrs) | 864,000 |
1 year (360 days) | 1,555,200 | 18 days | 15,552,000 |
10 years | 15,552,000 | 1 month (30 days) | 25,920,000 |
20 years | 31,104,000 | 2 months (60 days) | 51,840,000 |
You see from the above that in a single month,
the tungsten carbide already does the
work
of MC shutter cutter running for 17
years. It is obvious therefore a cutter of ordinary steel alone not comparable with the tungsten carbide blade. |