PED or 2006/42/EG machine directive?

[Robbert862]

Hey,

I am a student in the Netherlands, working on my final project for school to graduate.

I'm new to this forum, I subscribed because I have a question about a project that I am working on, but I'm kind of stuck. I have had contact with two different companies, one tells me that my project does fall under the PED, the other tells me it doesn't, and that is falls within the machine directive. I hope you guys can help me figure out wich one got it right.

I will describe my project as best as I can in Englisch

There is a company that produces compressorhouses for gas-turbine engines (the part where the pressure is build up with the rotating ventilators/turbineblades, before it goes to the combustionchamber). These compressorhouses need to be testet to make sure they are air tight. All the openings in the compressorhouse will need to be sealed off, then the house is filled with water, en brought to a pressure of 13,95 bar. If they stay on pressure for around an hour, they have passed the test.

My job is to design the seals and make sure they can withstand the pressure, along with rest of the installation like manometer and pressure overload protection. The pump used will be given to me by the company producing the compressorhouses. The assembled turbine engines will be used as generators in a powerplant.

The company saying the project does not fall within the PED, says it is excluded from it, according to paragraf 3.10 of the PED (page 5):

3.10
equipment comprising casings or machinery where the dimensioning,
choice of material and manufacturing rules are based
primarily on requirements for sufficient strength, rigidity and
stability to meet the static and dynamic operational effects or
other operational characteristics and for which pressure is not a
significant design factor. Such equipment may include:

- engines including turbines and internal combustion engines

- steam engines, gas/steam turbines, turbo-generators,
compressors, pumps and actuating devices;

(PED as PDF attachment)

http://files.engineering.com/getfil...-4760-94a5-40844e848566&file=PED_97-23-EC.pdf

He does not want to tell me why it is excluded from the PED using email. He wants to make an appointment to talk it over, for wich I need to pay ofcourse.

I hope that I have been able to explain myself clear enough, so that you guys can understand

Thanks in advance!

Robbert

 

[Robbert862]

I can not find a button to edit my post, forgot to tell something

To make sure I was clear on this, the installation I need to design is only for the purpose of testing the compressorhouses for their air tightness. The test installation will be used four times, and then is discarded.

Robbert

 

[Haralt]

Hello!

Why not ask your teacher or professor that is to support you during your project, what is valid?

The gasturbine manufacturer, by whom you are going to pressure test the gas turbine housing, must know very well if a pressure test of their gas turbine housing falls under the PED (Pressure vessel directives) or not.
I mean if this manufacturer already doing such pressure test of its gas turbine housings since many years.
Or is it a completly new gas turbine company without experince?

Please also look at Eng-tips posting policies, where it is clearly indicated:

Student posting in Eng-Tips forums for help with theses or coursework is forbidden.

Best regards
Haralt

 

[XL83NL]

Hello and welcome on eng-tips. Make sure to stay here over the years. This is a fantatsic place to discuss technical issues of all disciplines.

Although Haralt is right on student-posting, I believe the intent of your post is different from what Eng-tips tries to forbit. So Ill give this a shot.

Im Dutch myself too and worked with the PED for several years now. From my (humble) experience so far, I dont think this is classified as a PED item of pressure equipment. The exlcusion is pretty clear, and although there's a pressure housing in your gas turbine (it obviously needs to have one), significant design factor of the turbine is not to host or house pressure; it's a side effect.

Alternatively, you could either
- call a company like Siemens (in Hengelo, Overijssel) that makes such devices, and ask them how they handle this.
- call a notified body, like Lloyd's or DNV, and ask them.
We recently pruchased a steam turbine for one of our plants. The intent of that turbine is similar to your device in the PED context. Looking at our drawing of the turbine, I dont see notion of PED on it.

 

[hansv2]

Hi Robbert,
it all depends on the category of the pressure equipment.
the PED excludes pressure equipment that is incorporated in a machine, but only if it is up to category I (so, II, III and IV are in the scope of the PED). art 1.3.6
the machinery directive excludes (parts of) machines that also fall under another community directive in which the hazards are more specifically dealt with. article 3 (i think).

in the guidelines to the machinery directive the PED is specifically mentioned as one of those directives.

If you have any more questions you can contact me, free of charge ;-)

grtz
Hans

 

[Robbert862]

Hi everyone,

Thanks voor your reply's! I have had contact with Lloyd's Register, and with Euronorm. The whole problem was that those two company's were contradicting each other.

Yesterday I got an awnser from Euronorm wich is usefull:

If the pump is mounted directly on the seals, it can be seen as a whole, and can be seen as a compressor, wich then is excluded from the PED.

If the pump is not mounted directly on the seals, but standing next to it for example. The water is brought in the compressorhous through a hose or something, then it is included in de PED. It can then be seen as an external pressure vessel. The vessel and the hose/tubing will be included in the PED.

(the project falls under category I, module A by the way)

This awnser seems to make sense. For my project I am not net sure if the pump is mounted directly on the compressorhouse, or if it stands next to it, so I will have to wait for an awnser from the manufactuer of the compressorhouses, how they want to test it.

I can not get any help from my teachers, this project needs to be alone without much guidance from them. They will only check my reports and give it a go or no go.

The company for whom we excecute the project, I may not contact directly from my boss, so it need to go through him. He wants me to make a list of questions, instead of sending them a question each time I have one, wich makes sense ofcourse. For that reason I try to figure out as much as possible by my self

I appreciate the help you guys gave me. What do you think of the awnser Euronorm gave me?

Robbert

 

[hansv2]

Hello Robbert,
The answer from Euronorm is not correct. It makes no difference how the pump is mounted.
Although the pump has a pressure bearing housing, it is not primarily designed to retain pressure. The design is based on 'other aspects' (quote from PED). therefore it is excluded from PED by exception 3.6 in article 1 of the PED.

The answer from Lloyd's is probably correct. They are very experienced in that field.

grt Hans