astm a860 is the standard specification for wrought high-strength ferritic steel butt-welding fittings of seamless and electric fusion-welded construction. these pipe fittings shall be furnished in accordance with the dimensions of asme b16.9(for sizes nps 14 and smaller) or mss sp 75(for sizes nps 16 through nps 48). they can be further categorized into 6 grades: wphy 42, wphy 46, wphy 52, wphy 60, wphy 65, wphy 70. pipe fittings manufactured to astm a860 are usually used with api 5l line pipes and astm a694 high-strength forged flanges in high-pressure gas and oil transmission and distribution systems.
astm a860 specification covers wroughthigh – strength ferritic steel butt-welding fitting of seamless and electric and fusion-weldedconstruction covered by the latest revision of asme b16.9 and mss-sp-75 .butt-welding fittings differing from these asme and mss standards shall be furnishedin accordance with supplementary requirements s58 of specification a960/a960m .
chemical composition requirements of astm a860
the chemical composition of astm a860, % |
|
carbon |
≤0.20*a |
manganese |
1.00-1.45 |
phosphorus |
≤0.030 |
sulfur |
≤0.010 |
silicon |
0.15-0.40*b |
nickel |
≤0.50*c |
chromium |
≤0.30*c |
molybdenum |
≤0.25*c |
copper |
≤0.35*c |
titanium |
≤0.05 |
vanadium |
≤0.10 |
columbium |
≤0.04 |
vanadium plus columnium |
≤0.12 |
aluminum |
≤0.06 |
*the carbon equivalent c.e.=c+mn/6+(cr+mo+v)/5+(ni+cu)/15 shall not exceed 0.42%.
*b if vacuum carbon deoxidation is used, silicon shall not exceed 0.10% by heat analysis and 0.12% by product analysis.
*c the sum of ni+cr+mo+cu shall not exceed 1.0%.
mechanical properties of astm a860
astm a860/ 860m |
yield strength, min. |
tensile strength |
elongation, min. |
cv, avg./min. |
|||
grade |
ksi |
mpa |
ksi |
mpa |
% |
ft*lbs |
j |
wphy 42 |
42 |
290 |
60-85 |
415-585 |
25 |
30/25 |
40/34 |
wphy 46 |
46 |
315 |
63-88 |
435-605 |
25 |
30/25 |
40/34 |
wphy 52 |
52 |
360 |
66-91 |
455-625 |
25 |
30/25 |
40/34 |
wphy60 |
60 |
415 |
75-100 |
515-690 |
20 |
30/25 |
40/34 |
wphy 65 |
65 |
450 |
77-102 |
530-705 |
20 |
30/25 |
40/34 |
|