DESCRPTION
VHF-ST12 is Co-Cr-W alloy (Stellite) covered electrode. Its hardness is lower than that or NST-1, but its toughness and crack resistibility are better than those of NST-1. It is suitable for large weldments or in the case of gas welding is difficult to be applied.
APPLICATIONS
Hard surfacing of valve sleeves of high pressure pump, cutting knives, liner sleeves, valve seats and dies, etc.
INSTRUCTIONS FOR WELDING
1.) Preheat at 300ºC and over in general. Use VOLTAWELD temperature indicating sticks or NIHONWELD interpass temperature gauge to determine if proper temperature is achieve before welding. For more details see VOLTAWELD Chart 4 Easy Steps for welding.
2.) It is effective to postheat at 600ºC and to slow cool after welding to prevent cracking.
3.) Dry the electrodes at 150-200ºC for 30 – 60 minutes before use. Use VOLTAWELD portable drying ovens.
TYPICAL ANALYSIS OF ALL WELD DEPOSIT:
C |
Si |
Mn |
Cr |
Mo |
W |
Co |
|
|
1.43 |
0.56 |
0.98 |
31.62 |
- |
8.67 |
Bal |
|
|
HARDNESS:
AS WELDED: 42-48 HRC (410-490 Hv)
RECCOMENDED CURRENTS: Ampere (AC/DC+)
Size |
Dia |
3.2 |
4.0 |
5.0 |
(mm) |
Length |
350 |
350 |
350 |
Current Range |
90-120 |
110-150 |
140-180 |
WELDING POSITIONS:
FLAT, VERTICAL UP, OVERHEAD
EXPORT Packing: 5Kg plastic container, then 4 5kg containers in master carton box
LOCAL Packing: 5Kg paper box in shrink wrapped plastic
Other special packaging can be accommodated as per request. |
