First of all, thank you for reading my query and I will be hugely gratified for all the assistance and time that you will be providing. This problem has been nagging me from quite a time and I'll be truly glad if you can render me any help in sorting it out.
I have to select a material standard for stainless steel fittings complying with steel pipes as per ASTM A 312 TP304 (Welded). As per the tender specifications that I'm following, I have been given two choices namely ASTM A 182 (forged fittings) or ASTM A 403 (wrought fittings).
ASTM A 182 states :-
"Flanges of any type, elbows, return bends, tees, and header tees shall not be machined directly from bar stock"
So I'm guessing that in this case, rather than machining directly from bar stocks, the fittings will have to be manufactured by melting the austenitic steel and then forging it to shape by a forging machine such as a hammer, press, or ring rolling machine.
ASTM A 403 states :-
"The material for fittings shall consist of forgings, bars, plates, or seamless or welded tubular products"
and
"Forging or shaping operations may be performed by hammering, pressing, piercing, extruding, upsetting, rolling, bending, fusion welding, machining, or by a combination of two or more of these operations."
So again, I'm guessing that in this case in addition to manufacturing fittings by forging from molten steel and subsequently shaping them; there are other options of manufacturing fittings from plates or cold bending of seamless or welded tubular products which were not present in ASTM A 182.
So based on these observations I have two questions:-
1. What is the difference between both the standards in case of selecting austenitic steel fittings?
Other than that forgings are supposed to be manufactured from bar stocks and wrought fittings can be manufactured from forgings, bars, plates, or seamless or welded tubular products; is there any other difference?
F304 (as per ASTM A 182) and WP304 (as per ASTM A 403) both have the same chemical composition, mechanical properties and heat treatment requirements. So what is the difference between the forged and wrought fittings as denoted by these standards (for austenitic steel)?
2. Which standard should I select for fittings?
If both the forged and wrought products as per these standards have the same chemical composition, mechanical properties and heat treatment requirements, then which should I prefer and what should be the selection criteria? Is there any cost difference between these forged or wrought fittings? If so, then why?
Note:- The pipelines where the fittings will be used are for conveying demineralised water, alkali solution or scale inhibiting chemicals to CW forebay in a water treatment plant.
Design pressure - 8 kg/cm[sup]2[/sup]. Design temperature - 50 degree Celsius.
I'm quite new in this field so I will be glad if you can point out and clarify any misconception that I might have regarding these standards.
Thanks.
I have to select a material standard for stainless steel fittings complying with steel pipes as per ASTM A 312 TP304 (Welded). As per the tender specifications that I'm following, I have been given two choices namely ASTM A 182 (forged fittings) or ASTM A 403 (wrought fittings).
ASTM A 182 states :-
"Flanges of any type, elbows, return bends, tees, and header tees shall not be machined directly from bar stock"
So I'm guessing that in this case, rather than machining directly from bar stocks, the fittings will have to be manufactured by melting the austenitic steel and then forging it to shape by a forging machine such as a hammer, press, or ring rolling machine.
ASTM A 403 states :-
"The material for fittings shall consist of forgings, bars, plates, or seamless or welded tubular products"
and
"Forging or shaping operations may be performed by hammering, pressing, piercing, extruding, upsetting, rolling, bending, fusion welding, machining, or by a combination of two or more of these operations."
So again, I'm guessing that in this case in addition to manufacturing fittings by forging from molten steel and subsequently shaping them; there are other options of manufacturing fittings from plates or cold bending of seamless or welded tubular products which were not present in ASTM A 182.
So based on these observations I have two questions:-
1. What is the difference between both the standards in case of selecting austenitic steel fittings?
Other than that forgings are supposed to be manufactured from bar stocks and wrought fittings can be manufactured from forgings, bars, plates, or seamless or welded tubular products; is there any other difference?
F304 (as per ASTM A 182) and WP304 (as per ASTM A 403) both have the same chemical composition, mechanical properties and heat treatment requirements. So what is the difference between the forged and wrought fittings as denoted by these standards (for austenitic steel)?
2. Which standard should I select for fittings?
If both the forged and wrought products as per these standards have the same chemical composition, mechanical properties and heat treatment requirements, then which should I prefer and what should be the selection criteria? Is there any cost difference between these forged or wrought fittings? If so, then why?
Note:- The pipelines where the fittings will be used are for conveying demineralised water, alkali solution or scale inhibiting chemicals to CW forebay in a water treatment plant.
Design pressure - 8 kg/cm[sup]2[/sup]. Design temperature - 50 degree Celsius.
I'm quite new in this field so I will be glad if you can point out and clarify any misconception that I might have regarding these standards.
Thanks.