Introducing water mist technology – Part 2

Water mist expertise is still a comparatively new idea when it comes to fireplace suppression, but it’s proving to be an thrilling improvement in the trade. As the business evolves, so do the rules, laws and necessities in order to enhance safety and allow improvement. These can differ largely from nation to nation, and even area to area.
The method by which a water mist system operates is a similar mechanism to the standard sprinkler system in that the nozzles are normally activated via a bulb which blows at a particular temperature permitting for the activation of the mist through a low-pressure water piping system.
Here we have a look at how some water mist nozzles are produced and put in – from arriving as a big ‘bar’ of metallic, to becoming the environment friendly water mist nozzles we see installed in many new projects/developments throughout much of the globe at present.
The metal arrives for slicing
Here at Dual Mist Ltd, Stainless Steel 304 is used for lots of elements as it is extremely durable and corrosion resistant compared to other comparable metals. The physique is machined out of Brass CZ121, which arrives as giant bars of steel that are delivered to the warehouse in 3m lengths. This is then cut into two smaller components able to insert into the machine. Not all water mist corporations have the flexibility to machine the elements they require in-house though it can show very helpful for value and production purposes as we are about to see.
The metal is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine device is supplied with carbide tooling and high-pressure via coolant systems, with the twin-spindle and twin-turret making haste of the otherwise complicated parts. A Citizen M532 Sliding Head Lathe is used for the smaller parts.
A Citizen L12 also makes the filters with a functionality of drilling 365 holes in fifty one seconds, fully automated – this implies it can turnover an unimaginable 4,000 filters in a weekend completely unmanned.
The brass heads are additionally de-burred on the machine, eradicating all sharp edges earlier than being polished and sent for Electroless Nickel Plating. This offers a corrosion-proof coating to the brass, enabling it to turn out to be much more durable. All parts are then inspected for dimensional accuracy before the meeting stage.
This Technifor Laser machine engraves each nozzle in preparation for the testing phases.
There are many small components of assorted styles and sizes that make up the nozzle – In the DM4R nozzle, (as seen on the leak-testing pic) there are a total of thirteen parts or ‘components’. These elements are then meticulously put together and assembled by the production team requiring a good amount of labour earlier than the ultimate product is achieved. Various levels embody tightening with specially tailored instruments, pressing using a hand-press and using a particular ‘Locktite’ method at some stages which is a threadlock that prevents fixings from coming loose in the course of the operational lifetime of the product. The ultimate stage of assembly is fastidiously loading the bulb and making use of the proper load to it using a torque wrench.
The assembled nozzles are then positioned on another machine to have the ability to be labelled and uniquely identified utilizing a serial quantity. At compound gauge ราคา Ltd that is done on a Technifor Laser Engraver fitted with a 4th axis unit before they are able to be placed via the varied phases of testing.
Cull Testing
Also known as bubble testing in layman’s terms, this take a look at is to make sure no damage has occurred to the bulb during assembly and is a crucial check for LPCB approval. The check entails using a high-powered microscope to measure the size of the bubble in every bulb earlier than putting in warm water in order to shrink the scale 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 have the ability to ensure it has returned to the unique dimension inside a small tolerance.
Leak Testing
Every nozzle can also be stringently tested for leaks by applying 24-bar strain for 1 hour and making certain no water has escaped. It is uncommon for any leaks on the production line, however this is an especially very important stage of the testing as leaks might occur if filth is trapped inside the seal face.
Activation Testing
On a monthly foundation, random nozzles are also examined for activation by putting the nozzle on a stress jig at various pressures and applying warmth to the bulbs. The nozzles should all activate cleanly throughout the complete strain range specified to that nozzle.
A member of the manufacturing group uses a microscope and software to find out the dimensions of each bubble within the bulb.
At Dual Mist Ltd, these tests are not just to assure the quality of the production line but are additionally an necessary part of the LPCB Approval. These approvals enable customers to recognise that the products they are buying are made to the highest possible high quality commonplace in the area.
The drawback to this is that the Approval Testing system could be both expensive and time-consuming – typically needing to be booked several months prematurely and requiring years of exhausting work to attain.
The nozzles produced by Dual Mist have been put by way of their paces at BRE Global when it comes to each hearth testing and component/type approval.
Tamper proofing
In order to ensure that no one is tempted to interfere 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 fixed.
The nozzles are then able to be packaged and sent off for set up.
Here is an example of a control panel having been installed in The Claridges Hotel, London, UK. This is where the system is operated.
Rather than having to use the heavy and labour-intensive metal pipes typically utilized in high-pressure techniques, low-pressure water methods can use CPVC piping. This is a special kind of fire-resistant plastic enabling fast set up. Instead of threading every pipe, a heated glue can be used to shortly build large pipe networks. These networks are accredited to handle as much as 12 bar stress. The nozzles are screwed into a special pipe adaptor utilizing a half-inch fuel becoming.
An electric management panel is fitted for the system control along with pumps and a water tank, normally with a mains feed.
The system is examined, signed off and handed over to the consumer.
The last product once put in. This reveals how we anticipate to see the nozzles as quickly as a challenge has been completed.
As we will see there are many levels to go from metallic to nozzle head with each nozzle taking a significant effort by varied professionals to finish to the approved normal.
Not solely do water mist nozzles require multiple levels of machining and assembling, they must also bear a string of exams so as to be permitted for set up. Once put in, there are even additional checks undergone, sometimes by third-party organisations to guarantee that the complete fire suppression system to finally be handed over to the shopper.
Water mist expertise assures safety, high quality and assurance by way of the stringent testing that is required.
With the current publication of water mist standards, notably in Britain over recent years, building builders can now be assured that the quality required for water mist methods is now at an equal normal to other suppression methods.
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