Safety valves and block valves

In addition to the safety valves, in the catalog you can also find block valves that foresee uncontrolled leaks

The systems that carry combustible gases require precise and reliable control systems that can intervene in the event of an anomaly of any kind, avoiding accidents and even serious malfunctions that can compromise the operation of the systems themselves and endanger the people who are found in the vicinity of such failures. For this purpose, two main types of valves have been developed and are also present in the Gnali Bocia catalog: safety valves and block valves.

Characteristics of safety valves

The safety valves are a central component of the systems and can be regulated by two different mechanisms:
- the presence of the thermocopy detects the presence or absence of the flame. This mechanism is necessary to avoid uncontrolled leaks of combustible gas, reducing both waste and risks;

- control based on excess pressure with shutter that intervenes to block the flow in case of malfunction. The peculiar characteristic of this type of valves is that they can be reset only manually by specialized operators.

Characteristics of block valves

The block valves do not actually represent a separate category but represent a sub-group of safety valves regulated by excess pressure. A further advantage of this type of valve is that they can also be suitable for detecting the detachment of a pipe and preventing losses due to assembly.


Installation: a fundamental phase

Both for safety valves and for block valves, the installation phase is fundamental. In fact, it must be carried out by certified and adequately trained personnel who also know how to carry out all the necessary checks in order to obtain efficacy and safety. Continuous updating and the study of issues, in addition to compliance with regulations, is a must.


The importance of maintenance for the correct functioning of the valves

As with all safety components, the correct construction and calibration of the valves, as well as optimized assembly, are not a sufficient condition to guarantee optimal operation in service. In fact, over time, progressive losses of the calibration value can occur which can lead to various problems.
A first possibility of control is provided by a lever placed externally which, in systems that can be reached manually, ensures the carrying out of tests and allows blocking. This possibility, however, does not guarantee that the calibration value is respected. Therefore, further checks are necessary with the deposition of the valves on calibration benches with increasing air flows to bring them back to the default values. Finally, ultrasounds guarantee the control of leaks that may otherwise be difficult to diagnose and find.

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20/04/2022

See also

20/11/2021 Safety valves for gas blocking The characteristics of the gas block valves, safety first.

20/09/2021 Using safety valves equipped with thermocouple Safety valves for intercepting gas if the flame dies.

20/08/2022 Safety valve and assembly onto the water heater The safety and check valve must be fitted onto the water heater inlet for it to operate correctly

20/07/2016 Safety valves for the thermocouples in our catalogue. Safety valves made to satisfy the UNI EN 125 standard, a European harmonised standard that makes it possible to receive CE marking.

20/07/2021 The use of pressure stabilizers in agriculture What are price stabilizers, how they are produced and how they are installed in industrial and agricultural plants.