High Tech Root Coating

For Plastic Extrusion & Injection Molding Feed Screws

Specialized alloy coatings for root diameters, utilizing Flite Technology’s PLASMA-BOND welding system. Excellent bond strength and virtually no heat build up on screw.  Eliminates distortion and other problems associated with conventional welding methods. Now feed screw with sever root damage, heavy scoring and abundant pitting can be sectored to original tolerances and finishes. We can also reclaim worn screws that were rebuilt several times or subjected to improper polishing during rebuilding. Part or all of the root diameter areas can be coated. Korgard, our most popular repair alloy, is also chrome platable. Root coatings for use under extreme abrasive and corrosive conditions are also available. Standard screw base material ex. 4140 often lacks the properties for substantial longevity in these situations.


Listed below are a few of these coatings with comparative property data.
Chemical Compositions
Alloy Cr C Si Mn Mo Fe Ni Co B W Others
Cobalt-Base
FTPB-60 28 1.1 1 1* 1* 3* 3* Bal -- 4 --
Intermetallic Compounds
FTPB-400  8.5 0.08* 2.6 -- 28.5 -- -- Bal -- -- Ni+Fe=3*
FTPB-700  15.5 0.08* 3.4 -- 32.5 -- Bal -- -- -- Co+FE+3*
FTPB-800 17.5 0.08* 3.4 -- 28.5 -- -- Bal -- -- Ni+Fe=3*
+Major elements only     *Maximum     **Includes Ni

Comparative Average Hot Hardness Diamond Pyramid hardness (DPH), kg/mm2
  Test temperature, degrees F (degrees C)
  800 1000 1220 1400
Alloy (427) (538) (649) (760)
FTPB-60 300 275 260 185
FTPB-400 605 585 585 335
FTPB-700 540 510 410 245
FTPB-800 555 555 500 295
FTPB-150C 190 185 170 145

Comparative Average Abrasive Wear Data*
Alloy Volume Loss (mm3) Wear Coefficient**
FTPB-60 66 13 x 10-4
FTPB-400 29 7 x 10-4
FTPB-800 18 4 x 10 10-4
FTPB-150C 105 12 x 10-4
FTPB-700 51 13 - 10-4

*Tested for 200 revolutions at a load of 30 lbs (13.6 Kg) using a 9" (229mm) diameter rubber wheel and dry sand.
** Wear coefficient (K) is calculated from V = KPL/h, where V = wear volume in mm3, P = load kg; L = sliding distance in mm: and High h = diamond pyramid hardness. A combination of a low wear coefficient and High hardness is desirable for good wear resistance.


Comparative Average Adhesive Wear Data*
  Volume loss (mm3)
Alloy 90 lb. load (40.9 kg) 150 lb. load (68.2 kg) 210 lb. load (95.5 kg)
FTPB-60 1 2.6 9.5
FTPB-400 0.70 1.28 2.35
FTPB-700 0.07 0.09 0.19
FTPB-800 1.24 1.67 1.91
FTPB-150C 0.3 0.4 2.3
*Average of two or more tests in air against a case-hardened SAE 4620 steel ring (Rockwell C-63). Ring is rotated at 80 rpm. Total sliding distance is 2.2 x 105 mm.

Comparative Corrosion Data*
  Media, concentrations and temperatures
Alloy 30% formic acid, 150ºF (66ºC) 30% acetic acid, boiling 5% sulfric acid,
150ºF (66ºC)
65% nitric acid,
150ºF (66ºC)
FTPB-60 1 1 1 4
FTPB-400 2 1 2 4
FTPB-700 1 1 1 3
FTPB-800 -- 1 2 --
FTPB-150C 1 1 1 3
*Five 24hr. test periods.  Determined in laboratory tests.  Samples should be tested under actual plant conditions.
Code:
1 = less than 5 mpy (<0.13 mm/y)
2 = 5mpy (0.13mm/y) to 20mpy (0.51mm/y)
3 = more than 20mpy (>0.51 mm/y) to 50mpy (1.27 mm/y)
4 = more than 50mpy (>1.27 mm/y)

Comparative Average Charpy (Un-notched) Impact Strength*
Alloy ft. lb. J
FTPB-60 17 23
FTPB-400 3.5 4.1
FTPB-700 2 2.7
FTPB-150C >20 >27.1
*Undiluted deposits tested at room temperature
Tungsten root coatings are also available, plus other coatings for dimensionally changing root diameters.


Flite Technology, Inc. | phone: 800-327-9310 | 407-631-2050 | Fax: 321-636-3508