Globe valve standard clarification 2

[ARAK25]

Hi

I am buying 2" globe valve from a supplier. Our datasheet refers to design as per BS1873 whereas the supplier is offering design as per API607.
Which specification is stringent? Can some one throw some light?

Honestly I am struggling to read through both standard but it is certainly taking plenty of time to comprehend and interpret the standards.

The supplier says BS is outdated which is not the answer i expect but i need to know what the technical difference is between the two standards.

Thanks for your timely help.

 

[skengg]

Are u sure they saying globe valve design as per API 607?
Because as far as in know, BS1873 is dedicated standard specifically for steel globe valve design, whereas API 607 is a testing standard for soft seated quarter turn valves (e.g ball valves).
i assume u want to know the difference between BS 1873 and API 623. is it?

 

[ARAK25]

Hi SkEngg,

Sorry I was referring to API602 not API607.

Whats the key difference between BS1873 vs API602? Sorry for the previous confusion.

 

[skengg]

Well there's lot of difference between BS1873 and API 602, mainly depend on your requirements.
like API 602 covers valve only up to 4 inch whereas BS1873 covers small as well as large sizes valves,
and the reference design for API 602 (reference design means the design manufacturer provided when the purchaser does not specify.) is forged body/ bonnet bolted joint. API 602 widely popular in socket welding and threaded end valves and also unlike BS1873 , API 602 have the provision of reduce bore (which also called standard bore) and full bore design.
so unless u specify exact what specifications of globe valve you are buying, i can't conclude that whether u should agree to supplier or not?

 

[ARAK25]

Thanks for the reply.

As a purchaser I need 2" Globe valve, Regular Bore, Bolted Bonnet, OS&Y, Rising Stem, Straight pattern, renewable plug type Dics with handwheel operated. Please note the body material is Forged Duplex Stainless steel A182F51 (as proposed by supplier).

Disc, Stem, Back seat bush are UNS S31803


My requirement for testing was BS EN 12266 Part 1 and 2 leakage rate A whereas the supplier is offering API 598, so thats a next question why it is not tested to EN standards as requested?

When i enquired the supplier why not EN, supplier commented API602 refers to API 598 and it is equivalent or exceeds the testing requirement than EN standards. But when I asked to summarize there was no answer as well.

 

[skengg]

class?? end connection?

 

[ARAK25]

Class 1500, Flanged End Connection to ASME B16.5 RF. Face to Face dimension as per B16.1

 

[skengg]

though API 602 refers API 598 for testing.
overall both testing standards are equivalent, so if u ok with API 598 instead of BSEN 12266 then there's no issue.

 

[skengg]

well, in my point of view you can go for API 602 made globe valves as it satisfy your requirements, just confirm to them about whether they are providing standard bore or full bore globe valve?

 

[ARAK25]

well thats fine, there is no dispute on the testing standard as such but it was brought to my attention while checking the valve drawing and not during the bid stage. The major doubt is the API 602 vs BS1873 difference which I am struglling to find the technical differences to convince myself

 

[skengg]

as i said, there are differences in API 602 and BS1873,
but as per you requirements API 602 seems is compatible too, because API 602 widely used in smaller forged valves petroleum and natural gas industries.
and as i am working in valve manufacturer industry i would say BS1873 mostly used in as casting valves.

 

[skengg]

if you really want to go in detail then i guess reading standard only decent way to get elaborate answers as explaining differences will go clause by clause.

 

[ARAK25]

please see this attached image.

So what I understand from your feedback is BS1873 covers large size valves (upto DN400) whereas API 602 covers upto DN100 --> ok understood.
API602 and BS1873 both allows for casted and forged bonnet--> so i am not clear with your comment.
My requirement is a flanged globe valve, which i understand from the supplier it is a forged construction as single piece so the concern of socket welding or threaded end valve is not applicable here. Is that right?

So the another major differnece is regarding the full bore vs rgular bore query which i will clarify with them. From the drawing i attached it is regular bore, please can you confirm that

 

[skengg]

API602 and BS1873 both allows for casted and forged bonnet--> so i am not clear with your comment.
Yea both allows forged or cast component valves. i just explained what's more popular in valve industries, kindly read it carefully.

My requirement is a flanged globe valve, which i understand from the supplier it is a forged construction as single piece so the concern of socket welding or threaded end valve is not applicable here. Is that right?
YES.

Ok the bore dia. mentioned in drawing is equivalent to full bore valve as per API 602, in BS 1873 the bore dia. shall be 48 for 2 inch CL-1500 valves. so that's the one major difference. rest all differences are from design point of view which include stem dia, no. of packing used etc. if u really want to know about that then i already said you need to read standard as i cant copy paste whole standard here.

your supplier said "BS is outdated" that's only they gave statement in market point of view what's popular right now or not, that's not satisfactory answer.

 

[skengg]

i hope you understanding, as a general buyer point of view you need to be precise that how much information is necessary for u.

 

[ARAK25]

Sorry I didnt understand on the last comment you gave... "you need to be precise that how much information is necessary for u" as in?

 

[skengg]

Sorry I didnt understand on the last comment you gave... "you need to be precise that how much information is necessary for u" as in?

it only means that are you really wanna go deep into the standard, because i am keep repeating all the majjor differences between BS1873 and API602 which u need as a buyer point of view but it seems like you want to go in detail but also doesn't want to read the standard.
kindly read this lines from my last comment :-
"Ok the bore dia. mentioned in drawing is equivalent to full bore valve as per API 602, in BS 1873 the bore dia. shall be 48 for 2 inch CL-1500 valves. so that's the one major difference. rest all differences are from design point of view which include stem dia, no. of packing used etc. if u really want to know about that then i already said you need to read standard as i cant copy paste whole standard here."

so my question is are u really want to know every minor details? because it seems like you do want to but looking for any shortcuts where u find all the answer in just few lines.

 

[ARAK25]

Thanks SK, you have been really helpful in addressing my queries and taking time to patiently respond to very basic queries I had. I really appreciate that.

As I said I am new to valve spec standards and given the short time frame to review and return the drawings from the supplier I had to approach some experts like you through this forum.

Yes your understanding is right as per the last line but I will go through the standards as well based on the above comment you highlighted.

Once again thank you for your time and patience in educating me the major differences.

 

[skengg]

it's ok, just check out main highlight of standard and compare with your specifications.
the drawing u attached was general assembly drawing a valve manufacturer made for customers, in these type of drawings you won't get much design information. the information shown in drawing usually enough for customer so see if that drawing & written details satisfy your functional requirement or not. rest other information you will find in standard.

 

[ARAK25]

Thank you SK. I did compare both standards. Here is the high level summary I prepared, would you mind taking a quick glance and give your feedback?