4 replies to this topic

[Lipliki]

Hello, I´m new to this site, so, sorry if what I´m asking for can´t be responsed here.
I need information on single stage centrifugal compressors. I need to fill up the data sheets provided by API 617, inculding scrubbers, auxiliary services, etc for a compressor of the characteristics I mentioned. I have being looking for vendors but so far I haven´t found any that would give me enought information so that I can fill up the data sheets.
This is for my final university proyect (kind of a thesis), with a groups of students we are developing a plant for production of benzene from hydrodyalquilation of toluene, and I have to "by", hypothetically, a compressor. I have looked everywhere but no vendor provides the kind of information that I need, and to make it worst, I don´t really know much about compressors.
Can anyone tell me where I can find complete data sheets from vendors, including surge curves and everything I described?
Thanks a lot for reading and if what I´m asking for is out of place for this kind of forums, I apologize, as I said, I´m new to this site.
Regards,

[breizh]

Hi ,

You may find answers to your query in this ebook :
http://books.google....epage&q&f=false



Hope this helps

Breizh

[Art Montemayor]

Lipliki:

I don’t know where you are located or what university you attend. I also don’t know how familiar you are with the API and its Standards and Recommended Practices. I can only assume you are a Chemical Engineering Student. Please correct me on any wrong assumptions. My intention is to try to help you as a student – but not to do your work for you and much less to assist or aid you in making “short cuts” and obtaining information solely for the purpose of filling in a form that may be required to be done by you in order to judge and grade your work. Our purpose is to HELP students, not to show them how to avoid work and study. We don’t want ignorant students graduating into engineers and joining our ranks. That makes things dangerous for us and for the public.

I understand that your job on this project is to specify a centrifugal compressor for ultimate purchase, using the API 617 Data Sheets. I have various questions of you that I ask you to respond to:

• Do you possess a set of the subject Data Sheets? If you do, have you sat down and seriously studied them?
• Are you aware of the scope or intention of the Data Sheets?
• You state you are looking for “complete data sheets from vendors, including surge curves”. What do you mean by “complete” data sheets? A complete set of API 617 Data Sheets numbers 9 pages and that makes the set complete. (Refer to my attached document) Is that what you mean? Or are you looking for a set of Data Sheets all conveniently filled in for you by others? Why in the devil would you want surge curves? If you don’t “know much about compressors”, a set of surge curves would drive you crazy. Studying and learning about “Surge” in centrifugal compressors is hard enough as it is.

From what you write, I think you are mixed up about what your assignment really is. Please refer to the attached copy of the subject API Data Sheets. I believe your instructor (professor) wants and needs you to fill in the Data Sheets with the knowledge that you are seeking to purchase a Centrifugal Compressor and, for that reason, you should acquire some knowledge about what it is that you are supposed to purchase. That should be basic common engineering sense. It is only reasonable that if you are expected to spend several million dollars of your clients money that you know just exactly what it is that you are purchasing and WHY. Therefore, I strongly recommend that you quickly spend a lot of your time acquiring knowledge of the type and size of compressor you are about to specify – and that means all the components related to it – like the driver that will be selected for you (or by you), the lubrication system, the capacity controls, the surge controls (you had better find out all you can about surge and the need to protect against it), the instrumentation, etc., etc.. You don’t have an easy job ahead of you.

The primary purpose of an API 617 set of Data Sheets is to clearly, accurately, and specifically specify to a potential manufacturer the exact compression need that you are seeking to purchase. You do this in order to facilitate the design and cost estimation on the part of the manufacturer. The more you facilitate this for the manufacturer, the better off you will be with an accurate and timely cost estimate or proposal.

Note that the API 617 Data Sheets can be acquired in the native Excel spreadsheet form. You can acquire the Excel Workbook from the API – for a price. Or you can acquire the workbook from an engineer or your university department. I highly recommend that you prepare your Data Sheets in the spreadsheet format.

Look at the Data Sheets and let me walk you through some of the items.

On the first line of the first page, you will find that the information is “APPLICABLE TO” a proposal, a purchase, or to make the information “asbuilt”. You probably want to note it as for a proposal and you should color the circle that identifies this.

On line 8, you will see that the “INFORMATION TO BE COMPLETED” will be by PURCHASER (denoted by a circle), by MANUFACTURER (denoted by a square), or by A MUTUAL AGREEMENT (PRIOR TO PURCHASE (denoted by a triangle). Note that every subsequent line after line 11 has one of these symbols and you should, as a “purchaser”, fill in all the information accompanied by a circle. The manufacturer obviously is obligated to fill in that data accompanied by a square. Therefore, the scope of your work assignment – according to this document – is to fill in all the data requirements accompanied by a circle. It is that simple and direct. You, as a purchaser, furnish no “surge curves”. That is the responsibility of the manufacturer. I hope this clears up what you are mixed up about.

Now, as I have stated, you should acquire as much knowledge of the centrifugal compressor design that you are proposing to purchase. Obviously, you should also read the ENTIRE API 617 Standard (approximately 300 pages). And I assume you have been assigned a SPECIFIC version or edition of this document. There have been various editions and you should specify what edition you are working with.

While you might be responsible for preparing the Data Sheets, your team mates are probably responsible for feeding you the correct and specific process data that you need to identify the process conditions in the Data Sheets. This process data is items such as:

Line 13, Gas Handled
Line 15, MMScfd/Scfm (14.7 psia & 60 oF dry)
Line 16, Weight flow, lb/min
Line 18, Inlet pressure
Line 19, inlet temperature
And so on, and so on…..

All the information acquisition and reading you have to do should keep you very busy this Christmas season.

I hope this information has helped in making your project assignment a lot clearer and that you have a good grasp on what you have to do to make a good grade.

Attached Files

•  API 617 Centrifugal Compressor Sample Data Sheets.doc   1.21MB   52 downloads

[Lipliki]

Art Montemayor, thanks for taking the time to answer me in such an extended way.

I´ll answer some of your questions: I´m attending the "Universidad de Buenos Aires" (I´m argentinean, but I´m sure you can tell by the way I write in english).

Maybe I didn´n express myself quite as well: I don´t really know much about compressors, but that doesn´t mean I didn´t do my share of hard reading. I spent a month reading books and several recomended practices in order so select the type of compressor (single stage centrifugal). I was envolved in the entire proyect, that includes simulating our process in Aspen Hysys, so I know all there is to know about the process conditions and moreover, the gas conditions. I don´t expect anyone to do my work for me, the thing is that I have to hypothetically buy a compressor from a vendor, and based on that, fill up the data sheets provided by API 617. Since I don´t belong to any company, vendors don´t provide me with the information that I need, and since I don´t want to do a half work and invent information, what I was looking for was a link or something of that kind of a vendor that provides the complete information on their products without the need to actually buy them. The reason why I want the surge curves (and of course I know what surge is) is because I have to present them to me teacher along with the catalog of the compressor, in order for him to see that the compressor that I chose is in fact the right one for our process. All I wanted was a link of a vendor, that was all, because I have spend a lot of time visiting websites and the information they provide is not enough for me to be sure that their compressor is the right one for my process. I have to "pretend" to actually buy a compressor and fill up the data sheets as if the vendor had done it. That is my asignment.

I have read the API 617 and I know how to fill up the data sheets, but I´m not going to invent that information, I want to actually fill it up with a specific (any) vendor.

I just wondered if maybe someone knew of a vendor of that kind, that was all.
Thanks anyway for your time and I really apreciate the effort that implies answering like that.

[Lipliki]

Breizh:

Thanks!