HOWDEN Compressor WRViX stage

[Little Prince]

Dear All,
I want to select a HOWDEN compressor for compressing Methane from 5 bara to 30 bara with 21000 kg/hr mass flow. How is that possible in one single stage because of too much pressure difference?
when I try software to select nearest stage, it gives me warning because it select WRViX 365-193. What is the problem with this stage because of X variant?

thanks in advance

[HVACRsaurus]

These guys might be able to help you out..

Howden Process Compressors

Mail: hpc.sales@howden.com
Phone: +44 141 304 3500
Fax: +44 141 304 3600

Old Govan Road
Renfrew
PA4 8XJ
United Kingdom

[Little Prince]

Thanks for information.
As I understand X variant means it is high pressure series from Howden compressors and because of high pressure; exerted loads are close or exceed the bearing resistance hence they should evaluate the system in order to not facing any problem during operation.

[Josip]

Hi,Little Prince

Dear All,
I want to select a HOWDEN compressor for compressing Methane from 5 bara to 30 bara with 21000 kg/hr mass flow. How is that possible in one single stage because of too much pressure difference?
when I try software to select nearest stage, it gives me warning because it select WRViX 365-193. What is the problem with this stage because of X variant?

thanks in advance

No problem with selection software ... you need to contact Howden anyhow ... they can give you required compressor...

for your info: VRViX
W- wet i.e. oil injected
R- Refrigeration
V- volume control - with slide valve
i- infinitely variable volume from 2.2-5.0
X - eXtra high discharge pressure around 30 barg and oil pressure must be higher

Hope this help a little...

Best regards, Josip

[Little Prince]

One thing which I want to know, for shaft sealing system, does API Plan 52 counts for API conformity? We have to supply our Howden compressor with double shaft sealing system and as per Howden proposal we chose API PLAN 52, but our Client decline to accept because they think it is not according to API 619-614 regulation.
Please advise.

[Josip]

Hi, Little Prince

One thing which I want to know, for shaft sealing system, does API Plan 52 counts for API conformity? We have to supply our Howden compressor with double shaft sealing system and as per Howden proposal we chose API PLAN 52, but our Client decline to accept because they think it is not according to API 619-614 regulation.
Please advise.

To be honest I do not know what is exactly written in API 619-614 regulation ...because I do not have those regulation, but, check this link .... pages 4,5,6
http://www.howden.com/NR/rdonlyres/7...ompressors.pdf

This would be acceptable for process screw compressor, but doing my jobs all around the world sometimes I met Client's personnel asking questions and expressing some doubts regarding installed plant/s. Some question/s were OK and some just showed that operators are not at home within the field they have to operate and take care.

here are some more shaft seal plans by John Crane
http://www.google.hr/url?sa=t&rct=j&q=&esrc=s&source=web&cd=12&cad=rja&sqi=2&ved=0CG4QFjAL&url=http%3A%2F%2Fwww.kupujucpa vky.cz%2Fe-catalogue%2FDataSheets%2FOther%2FAPI_plans_poster.pdf&ei=KGqzUdesF4mp4ASP4oCQDw&usg=AFQjCNG-9NuaMjgzuQT2_ywN2Z4xQKyHGA&sig2=otxKlV1_Fps1KK2h-Gm6ZA&bvm=bv.47534661,d.bGE

http://www.aesseal.com/apiplan.aspx/1/Oil-and-Gas


Please, check this link too: http://www.eng-tips.com/viewthread.cfm?qid=157105
post #4 JJPellin

Plan 52 is a double seal. Leakage of the primary seal can be detected because product will be leaking into the seal pot. If the product tends to vaporize at flare pressure, the leak will be detected by pressure increasing behind the orifice in the vent line. If the product tends to remain liquid at flare pressure, the level in the pot can be seen to rise by the operators on normal rounds. If they fail to notice and the pot becomes full of liquid up to the orifice, then pressure will back up and be detected. A leak of the outer seal can be detected by visible leakage of the barrier fluid to the base. Also, the level of fluid in the pot could be seen to drop. However, in some services, depending on the barrier fluid used, the level could drop slightly just from barrier fluid vaporizing to flare. We see this with #1 fuel oil barrier fluid in not services. A loss of level in the pot is typically seen by operators on normal rounds checking the sight glass. A low level switch could also be used, especially for remote or unmanned installations to detect outer seal leakage.

as described it is normal double seal installation regarding safety .... furthermore it is possible to install a few gas sensors around the unit to be sure there is no gas leakage or in case of leakage it will be discover immediately. Nothing is 100% sure and safe.

Hope this is of some help.

Best regards, Josip