Introducing water mist technology – Part 2

Water mist technology is still a comparatively new idea when it comes to fire suppression, but it’s proving to be an thrilling growth within the business. As the trade evolves, so do the laws, laws and requirements so as to improve safety and enable development. These can vary largely from nation to country, and even area to region.
The method by which a water mist system operates is a similar mechanism to the traditional sprinkler system in that the nozzles are usually activated by way of a bulb which blows at a selected temperature allowing for the activation of the mist by way of a low-pressure water piping system.
Here we take a look at how some water mist nozzles are produced and installed – from arriving as a big ‘bar’ of metal, to becoming the environment friendly water mist nozzles we see installed in plenty of new projects/developments throughout a lot of the globe at present.
The steel arrives for slicing
Here at Dual Mist Ltd, Stainless Steel 304 is used for a lot of elements as this may be very sturdy and corrosion resistant in comparison to different similar metals. The physique is machined out of Brass CZ121, which arrives as giant bars of metallic which are delivered to the warehouse in 3m lengths. This is then minimize into two smaller elements able to insert into the machine. Not all water mist companies have the power to machine the components they require in-house although it can show very useful for value and production functions as we are about to see.
The steel is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine software is provided with carbide tooling and high-pressure through coolant methods, with the twin-spindle and twin-turret making haste of the otherwise sophisticated parts. A Citizen M532 Sliding Head Lathe is used for the smaller elements.
A Citizen L12 additionally makes the filters with a functionality of drilling 365 holes in fifty one seconds, fully automated – this means it might possibly turnover an unimaginable four,000 filters in a weekend utterly unmanned.
The brass heads are also de-burred on the machine, eradicating all sharp edges earlier than being polished and sent for Electroless Nickel Plating. This provides a corrosion-proof coating to the brass, enabling it to become much more sturdy. All elements are then inspected for dimensional accuracy before the assembly stage.
This Technifor Laser machine engraves each nozzle in preparation for the testing phases.
There are many small components of various sizes and shapes that make up the nozzle – In the DM4R nozzle, (as seen on the leak-testing pic) there are a complete of thirteen parts or ‘components’. These parts are then meticulously put together and assembled by the production group requiring a good amount of labour before the ultimate product is achieved. Various levels include tightening with specifically tailored tools, urgent using a hand-press and using a selected ‘Locktite’ formula at some levels which is a threadlock that forestalls fixings from coming free through the operational lifetime of the product. เกจปรับแรงดันแก๊ส of assembly is carefully loading the bulb and making use of the right load to it using a torque wrench.
The assembled nozzles are then placed on another machine in order to be labelled and uniquely recognized using a serial number. At Dual Mist Ltd this is accomplished on a Technifor Laser Engraver fitted with a 4th axis unit earlier than they’re ready to be positioned through the various phases of testing.
Cull Testing
Also often recognized as bubble testing in layman’s phrases, this test is to make sure no injury has occurred to the bulb throughout assembly and is a crucial test for LPCB approval. The check includes utilizing a high-powered microscope to measure the scale of the bubble in every bulb before putting in warm water to be able to shrink the dimensions of the bubble to nothing. Once that is checked, the nozzles are then left to relaxation and return to room temperature before the bubble is measured as quickly as once more to find a way to guarantee it has returned to the unique dimension inside a small tolerance.
Leak Testing
Every nozzle can additionally be stringently examined for leaks by applying 24-bar stress for 1 hour and guaranteeing no water has escaped. It is uncommon for any leaks on the production line, however this is an extremely vital stage of the testing as leaks may occur if filth is trapped within the seal face.
Activation Testing
On a monthly basis, random nozzles are also examined for activation by placing the nozzle on a pressure jig at varied pressures and applying warmth to the bulbs. The nozzles ought to all activate cleanly across the whole strain vary specified to that nozzle.
A member of the production group uses a microscope and software to find out the scale of every bubble within the bulb.
At Dual Mist Ltd, these exams are not just to guarantee the quality of the production line but are additionally an necessary part of the LPCB Approval. These approvals allow prospects to recognise that the products they’re shopping for are made to the best attainable quality standard in the area.
The disadvantage to that is that the Approval Testing system can be both expensive and time-consuming – sometimes needing to be booked several months upfront and requiring years of exhausting work to attain.
The nozzles produced by Dual Mist have been put through their paces at BRE Global in phrases of each hearth testing and component/type approval.
Tamper proofing
In order to guarantee that no person is tempted to intrude with the grub screw holding the bulb, a small plastic bung is pressed into the grub screw. The strain load setting on the bulb is then subsequently mounted.
The nozzles are then able to be packaged and despatched off for installation.
Here is an example of a management panel having been installed in The Claridges Hotel, London, UK. This is where the system is operated.
Rather than having to make use of the heavy and labour-intensive metal pipes typically used in high-pressure systems, low-pressure water methods can use CPVC piping. This is a particular kind of fire-resistant plastic enabling quick set up. Instead of threading every pipe, a heated glue can be utilized to shortly construct giant pipe networks. These networks are permitted to deal with as much as 12 bar strain. The nozzles are screwed into a particular pipe adaptor using a half-inch gasoline fitting.
An electric management panel is fitted for the system control along with pumps and a water tank, usually with a mains feed.
The system is examined, signed off and handed over to the client.
The last product once put in. This shows how we anticipate to see the nozzles as quickly as a challenge has been completed.
As we can see there are heaps of phases to go from steel to nozzle head with every nozzle taking a significant effort by various professionals to complete to the approved normal.
Not only do water mist nozzles require a quantity of stages of machining and assembling, they want to additionally bear a string of checks to be able to be approved for set up. Once put in, there are even additional exams undergone, generally by third-party organisations to guarantee that the complete fireplace suppression system to finally be handed over to the consumer.
Water mist technology assures security, high quality and assurance through the stringent testing that is required.
With the recent publication of water mist standards, significantly in Britain over recent years, building developers can now be assured that the quality required for water mist methods is now at an equal normal to different suppression techniques.
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