API 594 Swing Check 1

[HitokiriAoshi]

Can anyone with experience explain why no one ever ask for API 594 Type B Swing Check. Bur rather, ask for "API 600" Swing check.

I understand API 594 have many additional requirements that makes manufacturing them more troublesome, but i am just wondering why, the industry even bother to have a spec, if no one wants them or makes them.

Regards,

 

[stanier]

The definitons below are from engineeringtoolbox.com. API600 would appear to be for gate valves?

•ANSI/API 600
Bolted Bonnet Steel Gate Valves for Petroleum and Natural Gas Industries - Modified National Adoption of ISO 10434:1998.
•ANSI/API STD 594
Check Valves: Flanged, Lug, Wafer and Butt-welding. API Standard 594 covers design, material, face-to-face dimensions, pressure-temperature ratings, and examination, inspection, and test requirements for two types of check valves.

"Sharing knowledge is the way to immortality"
His Holiness the Dalai Lama.

http://waterhammer.hopout.com.au/

 

[reverman]

Technically API 600 is only a gate valve spec. However most of the industry incorrectly refers to it when specifying checks and globes.

API 594 should be used for check valves. For the most part it is the API 600 of check valves however it has a couple odd manufacturing requirements that many standard designs do not meet (ex. limits on disc rotation) so therefore it seems to not get invoked very often.

So what what most people really want is a check valve that meets the "applicable parts" of API 600 which generically means Wall thickness, trim materials, etc.

API is currently developing API 623 which will be for globe valves. Currently API has no globe valve standard

 

[HitokiriAoshi]

yah, I participate with the process of developing that new spec, now i am just worried that this would become another "594" where it's there, but no one bother to make or demand it.

I know a couple major companies would just plainly put API 600 check valve on their catalogue, and googling api 594 swing check would turn up only misc Chinese manufacturers. I even had end-users demanding me to put API 600 on the drawings of our check valves as design standards.

the exact differences between API 594 swing and BS 1868 are as follow.

1) disc nut must be positively secured
2) disc must not swivel 360 degrees
3) top bonnet/cap must be calculated per ASME PBV VIII UG34 and UG35. which can yield more stringent requirement when compared to BS 1868 w/ API 600 wall thickness.

So I guess really the question is, anyone, here, EVER, bought, requested, provided API 594 type B swing check valve? Seems like a dead spec to me =/

 

[stanier]

No doubt there are many consultants out there who list every standard they come across in their specifications without knowledge of the content. In my 40+ years in the business I have come across such ignorance so often accompanied by the words that the contractor "shall comply with most ardous conditions" in any of the standards.

From a legal perspective this cannot be enforced as the provision is too wide and embracing. Also the matter of "in contra preferentum" applies.

http://en.wikipedia.org/wiki/Contra_proferentem

So if you are one of those silly engineers who thinks they are protecting their client or that they will get a better product by such actions I suggest your read the above article.

Before specifying a standard you, the enginner, needs to understand what that standard covers.

"Sharing knowledge is the way to immortality"
His Holiness the Dalai Lama.

http://waterhammer.hopout.com.au/

 

[stanier]

Here is one example of a Type B to API 594 from a reputable manufactuer.

http://www.kitzus-kca.com/pdf/check_low/check150.pdf

Check Valves: Flanged, Lug, Wafer, and Butt-welding

SEVENTH EDITION | SEPTEMBER 2010 | 21 PAGES
PRICE: $102.00 | PRODUCT NO. C59407

This international standard covers design, material, face-to-face dimensions, pressure-temperature ratings, and examination, inspection, and test requirements for two types of check valves.

Type ‘A’ check valves are short face-to-face as defined in Table 3 and Table 4 and can be: wafer, lug, or double flanged; single plate or dual plate; gray iron, ductile iron, steel, nickel alloy, or other alloy designed for installation between Classes 125 and 250 cast iron flanges as specified in ASME B16.1, between Classes 150 and 300 ductile iron flanges as specified in ASME B16.42, between Classes 150 and 2500 steel flanges as specified in ASME B16.5, and between Classes 150 and 600 steel pipeline flanges as specified in MSS SP-44 or steel flanges as specified in ASME B16.47.

Type ‘B’ bolted cover swing check valves are long face-to-face as defined in 5.1.2 and can be: flanged or butt-welding ends of steel, nickel alloy, or other alloy material. End flanges shall be as specified in ASME B16.5 or ends shall be butt-welding as specified in ASME B16.25.

This standard covers the following ranges:

Type ‘A’ valves:
Classes 125 and 250, 50 = DN = 1200 (2 = NPS = 48) (excluding DN 90 [NPS 31/2]); Classes 150 and 300, 50 = DN = 1200 (2 = NPS = 48)*;
Class 600, 50 = DN = 1050 (2 = NPS = 42)*;
Classes 900 and 1500, 50 = DN = 600 (2 = NPS = 24)*;
Class 2500, 50 = DN = 300 (2 = NPS = 12)*;

Type ‘B’ valves:
Classes 150 through 1500, 50 = DN = 600 (2 = NPS = 24)*;
Class 2500, 50 = DN = 300 (2 = NPS = 12)*.
NOTE *Valve sizes DN 90 and DN 125 (NPS 31/2 and 5) are non-preferred sizes whose usage is discouraged.

Sizes:

NPS: 2, 2 1/2, 3, 4, 6, 8, 10, 12, 14, 16, 18, 20, 24, 30, 36, 42, 48;

corresponding to nominal pipe sizes DN:

DN: 50, 65, 80, 100, 150, 200, 250, 300, 350, 400, 450, 500, 600, 750, 900, 1050, 1200.

Information to be specified by the purchaser is shown in Annex A.


"Sharing knowledge is the way to immortality"
His Holiness the Dalai Lama.

http://waterhammer.hopout.com.au/

 

[HitokiriAoshi]

Thank you, that is one of the first example that I've seen with literature indicating as such.

Appreciate it.