Maintenance
Predictive maintenance of safety devices thanks to intelligent measurement technology
Flame arresters and breather valves are widely used in the industry and are required to always be fully operational . Proper maintenance is of great importance , as the consequences of any failure can be devastating . Martin Hundt explains how intelligent measurement technology can make a difference .
By Martin Hundt , KITO Armaturen GmbH
About the author Martin has almost 15 years of experience in the chemical , petrochemical , pharmaceutical and food industries . His focus lies in safety valves : design , installation and operation , which is all very handson . Within the framework of Huckauf Ingenieure GmbH ’ s academy , he acts as a speaker and moderator on a wide range of topics . His main aim is to impart specialist knowledge and content to the participants . For more information , please visit www . kito . de .
Flame arresters and breather valves are used in various applications in the industry , such as in storage tank farms , processing systems , vapor combusting systems , flare , and incineration systems , in loading and unloading processes in logistics , in vapor recovery units or as integrated components of equipment . All these industries now benefit from digitisation and Industry 4.0 , which is finding its way into the field of safety devices . Flame arresters and breather valves safeguard the mentioned systems and , owing to continuous usage and the demand for uninterrupted availability , must always remain fully functional at 100 %. The failure of a device can have devastating consequences . Generally , maintenance intervals for devices should be established based on the operator ’ s operational experience . According to the German Industrial Safety Ordinance ( BetrSiVO ) under § 15 , protective systems such as flame arresters or venting valves with integrated flame arresters must undergo an inspection by the approved inspection agency prior to start-up and before re-commissioning after mandatory changes . This includes a risk assessment according to § 3 , section 6 of the German Industrial Safety Ordinance ( BetrSiVO ), where the employer is responsible for determining the type , scope , and deadlines for the required inspections . For new installations , it is advisable to allocate a conservative time period , which depends on various factures such as :
• The design of the device
• The construction material in terms of potential corrosion and fouling
• The operating pressure and temperature
• The fluid that may contain contaminants or solid particles , polymerise , or be viscous
• The cyclic , static , or changing operating conditions within the plant
Figure 1 . KITO ( R ) VD / oG-PA , pressure and vacuum relief valve with dual proximity switch .
For recurring inspections according to § 16 of the German Industrial Safety Ordinance , the recommended manufacturer ’ s instructions should be followed . These intervals can be extended if an effective maintenance concept according to German Industrial Safety Ordinance § 16 , Number 4.1 has been formulated in consultation with the approved inspection agency . This can change the prescribed recurring inspections from 3 to 6 years . These defined maintenance intervals must be adhered to and documented . They can be adjusted , shortened , or extended based on the operator ’ s experience in consultation with the qualified person , who possesses specialised knowledge in explosion protection , or the approved inspection agency . Despite all these recommendations , there are no calculation models or standards available to calculate and / or ensure the functionality of the valves . In order to optimise this iterative process , digitalisation is now being employed . Additionally , digitalisation can assist operators , particularly those with limited operational experience , in their decision-making process for defining maintenance intervals . These intervals are often estimated very conservatively , which can significantly reduce plant availability . The further development of digitisation can now compensate for a lack of operating experience as well as the challenge of the various applications and operating conditions within an existing system . Thanks to the implementation of intelligent measuring technology , operators are now able to monitor the real-time operating status of the safety devices , access device statuses , and proactively schedule preventive maintenance or repair work in advance . This not only prevents devices failures but also ensures maximum system availability , allowing for optimal scheduling of maintenance work .
The challenge of monitoring breathing valves
Breathing valves can experience failure due to various factors , such as mechanical issues with
Figure 2 . Sectional drawing of a proximity switch on a weight loaded valve .
Figure 3 . KITO ( R ) VD / Sc-1 , Inline pressure or vacuum relief valve with proximity switch .
48 Valve World August 2023 www . valve-world . net