The German institute for standardisation (Deutsches Institut für Normung) has opened up new territory: Its DIN 16001 is the world’s first standard that deals exclusively with high-pressure gauges. In accordance with the criteria described within it, WIKA is at the forefront of manufacturers, launching two new measuring instruments of this type, the models PG23HP-P and PG23HP-S.
Safety is an important factor in processes, particularly in the high-pressure ranges. High-pressure gauges, specifically, must cope with heavy loads in order to withstand critical situations. However, so far, there has been no appropriate standard for manufacturers, buyers or users to follow. This is because the only standard for mechanical pressure measuring instruments till now, EN 837-1, is only valid for pressures up to and including 1,600 bar.
The new PG23HP-P high-pressure gauge is already constructed and qualified in accordance with the DIN 16001 standard. The triangular limitation mark in the picture section shows the maximum value of the continuous pressure limitation.
Most important provisions for high-pressure gauges
Thus, until the publication of DIN 16001, every manufacturer could build their high-pressure gauges as they wished and market them without marking. The new standard, initiated by companies such as WIKA, now creates clarity. It is based strongly around EN 837-1, defining, however, specific criteria for high-pressure gauges. Here is an overview of the most important provisions:
- DIN 16001 is valid for measuring instruments with scale ranges from > 1,600 bar up to 10,000 bar (nominal sizes 100 and 160).
- All high-pressure gauges which are constructed in accordance with DIN 16001 must also be manufactured and qualified, without exception, to safety category “S3”. This requires a case with laminated safety glass, a solid baffle wall between measuring system and dial and a blow-out back. Through this, in the event of a failure, the operating personnel are protected at the front side, as media or components can only be ejected via the back of the case.
- The continuous pressure limitation of high-pressure gauges, in accordance with DIN 16001, lies at 75 % of the full scale value. For short periods, the instruments can be loaded to the complete full scale value. The instrument should not be exposed to any pressure that exceeds the full scale value.
Extensive qualification of the high-pressure gauges
WIKA has constructed, qualified and correspondingly marked both of its new high-pressure gauges in accordance with DIN 16001. The qualification is very extensive, especially due to the safety-relevant type testing. This requires specialised equipment, which WIKA has.
The model PG23HP-P features scale ranges of up to 6,000 bar and a high indication accuracy of up to class 0.6 %. Its load cycle stability far surpasses the minimum requirements of the standard (10,000 load cycles at pressures up to 5,000 bar, 5,000 load cycles at pressures from 5,000 bar up to 10,000 bar). The model PG23HP-S is available with scale ranges up to 3,000 bar and an accuracy class of 1.6 %. It has been designed mainly for price-sensitive applications.
Note
Further information on the models PG23HP-P andPG23HP-S can be found on the WIKA website. Additional information on DIN 16001 can be found on the website of the German institute for standardisation (Deutsches Institut für Normung – DIN).