PSV transportation after calibration

[nasim123]

Dears
We would like to test & calibrate our new psvs in RV shop, which is more than 180KM far from our plant. As per code/API, is it acceptable? After calibration, how many kilometer transportation is acceptable(by road)?

Can we have your advice pls

Thanks

 

[The Obturator]

Hi nassim123 It is the end users (and/or plant insurers), choice whether SRV's are retested after receipt from manufacturer or other. In any case, if it is to be done, it is generally assumed that testing is at installation location. Therefore, no transportation is taken into account. As far as I am aware, no distance etc., is stipulated in any known standard.

As an ex SRV manufacturing plant person, I would advise you that for transportation, shipment is to be free from knocks, drops, un-level and handling, which in itself is impossible, hence end users want to check the setting. The crux of the matter here being that any knock that the SRV may experience, may well alter the factory setting (movement of seats, spindle, guiding etc). This is more so on larger size SRV's.

There is still a school of thought in this world that specifies "shipping rods". These are actually the hydrostatic test rods used in the cap of the SRV to block the SRV. This is when hydrostatic testing of vessel is being done. Someone, many years ago, thought it would be a good idea to specify these rods already inserted (rather than just the plug as in normal/active service), in order to ensure that the seats are maintained together during shipment !

This is dangerous practice as there have been instances where the SRV has been installed as such. So basically, a blind flange is the result and no overpressure protection). Some SRV companies still do this with distinctly large warning labelling.

Therefore your 180 Km transportation would need to be very carefully observed throughout the time of transit. Meaning that the overland terrain needs to be of proper highway standard.

Finally, I would recommend the transportation of any SRV in the vertical (spring above disc) position.

Hope this provides some insight.

Per ISO, only the term Safety Valve is used for all overpressure eventualities regardless of design.