Safe isolation

Options and opportunity

Bellows Sealed Stop Valve Installation

Angelo Giambrone, Business Development Manager , 27/06/2019

When unplanned downtime of critical plant equipment rears its head, it can bring with it the nightmare scenario that multiple essential processes are put out of action when you need them most. Angelo Giambrone, Business Development Manager at Spirax Sarco highlights the importance of safe and effective plant isolation for planned or unplanned maintenance.

Providing effective isolation exactly where and when you want it should be a given, allowing you to focus on the task in hand. It’s important to understand the options available to help you choose the solution that offers safe and effective plant isolation each and every time. 

Staying single

Some facilities in the UK continue to make use of a single valve, without a bleed, as the means of isolation. This brings with it several challenges and poses a risk to the safety of the facility, with potential financial consequences as well. 

Single isolation for the modern steam plant does not always provide a leak-tight seal – even a minor leak could make the maintenance task unsafe and pose a risk to you and your colleagues. You may find that you’re unable to carry-out timed routine maintenance or an emergency system shutdown, resulting in the closure of entire sections of the facility. 


The double block and bleed (DBB) isolation method offers an alternative to the risky use of single isolation. Traditionally this was achieved using separate valves, two in a line and one as a bleed, but the installation of all these valves could lead to you spending more than you need in upfront investment of both time and money. 

Using separate valves for DBB means you’ll need to find more space to fit them. In a new installation, a larger plant room may have to be considered during the design process.

The alternative

The alternative is simple but effective – two bellows sealed isolation valves in the space of one valve body - the Spirax Sarco SafeBlocTM. The technology is faster to install than a traditional DBB assembly, because it can be installed into the space left by an existing single isolation valve.

The amalgamation of two valves into one body means that there are less flanged connections in the overall installation, thus lowering the risk of flange leaks. 

A simple-to-install solution, the SafeBlocTM has been designed to meet the increased demands of health and safety requirements where traditional single isolation of plant is inadequate. Offering further protection for those safety-conscious maintenance engineers, the SafeBlocTM helps you to meet the DBB standards of the HSE. 

The safety and efficiency delivered with the installation of a DBB bellows sealed isolation valve such as SafeBlocTM can bring you peace of mind while protecting the integrity of your steam system. 

Why not find out more about how SafeBlocTM can help you >>


Angelo Giambrone
Business Development Manager