Since any defect in the pipe or armature could cause material damage and endanger human lives, natural gas transportation must be safe. Therefore, ball valves for gas pipelines located in the Member States of the European Union require certification according to EN 14141.

"Preparing for this test is very challenging because the standard sets the DN intervals for which we had to design, draw, produce and test individual samples. There are eight samples: three K91 DN 25 samples in different designs and five K92 samples (DN 100, 2x DN 300, DN 500 and DN 750). For this certification, the standard requires typing tests that are more demanding than regular manufacturing tests. The higher difficulty for type tests than standard testing ensures that an unidentified deviation in normal production does not affect the safety of operation. All inspections and tests were under 100% control by the Inspector of the State Testing Institute in Brno ", says product certification specialist Ing. Daniel Drobík.

The DVGW certificate requires special functional tests

The ARMATURY Group ball valves have successfully passed a clean gas test. Their purpose was to determine the ability to operate under the influence of clean gas in a corresponding operation. The test medium was air; the DN 100 valves were subjected to 200 cycles and valves of larger dimensions to 100 cycles under differential pressure. A torque test and seat leakage test were performed before and after the test.

The second test was much more demanding, and it aimed to determine resistance to abrasion by solids contained in the gaseous medium. The device must be equipped with a large air reservoir so that the air flow rate through the valve in the open position is about 10 m/s. The test is carried out on the 600 mm DN 300 valve. In this test 20 open and close cycles were performed in the presence of solid contaminants - impurities.

All tests results were passed to the Engineering Testing Institute in Bonn at the DVGW Headquarters for expert judgment. Its confirmed the successful execution of these exams and released ARMATURY Group a.s. required certificates. This again proved that an engineering company based in Dolní Benešov with a long tradition could meet even the most demanding requirements for product quality.