nihonweldnihonweldnihonweld

Printer Friendly Layout
NHF-ST1
AWS Specification: ECoCr-C
JIS Specification:

D CoCr-E

Other Specification:

I. APPLICATIONS:

 

Hard surfacing of valve heads, seal rings of high pressure pump and parts of crushers.  

II. DESCRIPTION:

NHF-ST1 covered electrode is the highest hardness standard alloy in the group of cobalt alloys used for elevated temperature abrasive wear associated with corrosion. Deposits of this alloy have a large volume of chromium carbides that impact outstanding abrasive wear resistance. The addition of tungsten enhances high temperature hardness and matrix toughness for excellent adhesive and solid particle erosion wear resistance. It bonds well with all steels, including stainless.

III. NOTES ON USAGE:

 

  • Preheat at 300ºC and over in general.  Use NIHONWELD temperature indicating sticks or NIHONWELD interpass temperature gauge to determine if proper temperature is achieve before welding. For more details see NIHONWELD Chart 4 Easy Steps for welding. 

  • It is effective to postheat at 600ºC and to slow cool after welding to prevent cracking.

  • Dry the electrodes at 150-200ºC for 30 – 60 minutes before use. Use NIHONWELD portable drying ovens.

IV. HARDNESS OF WELD METAL DEPOSIT : 50 – 56 HRC (520- 620 Hv)

V. TYPICAL CHEMICAL COMPOSITION OF WELD METAL (%):

 

C

Si

Mn

Cr

W

Co

2.15

0.47

1.03

31.25

12.72

Bal

VI. WELDING POSITION: FLAT, VERTICAL UP, OVERHEAD

VII. SIZES AVAILABLE AND RECOMMENDED CURRENTS ( DC + ):

 

Size (dia. mm)

3.2

4.0

5.0

Length (mm)

350

350

350

Current Range (Amp)

90 - 120

110 - 150

140 - 180