Introducing water mist know-how – Part 2

Water mist know-how remains to be a comparatively new idea when it comes to fire suppression, but it is proving to be an exciting growth within the business. As the industry evolves, so do the laws, laws and necessities so as to enhance security and allow development. These can range largely from country to nation, and even region to area.
The method by which a water mist system operates is an analogous mechanism to the traditional sprinkler system in that the nozzles are normally activated by way of a bulb which blows at a selected temperature permitting for the activation of the mist via a low-pressure water piping system.
Here we have a look at how some water mist nozzles are produced and installed – from arriving as a large ‘bar’ of metal, to becoming the environment friendly water mist nozzles we see installed in plenty of new projects/developments throughout much of the globe at present.
The steel arrives for slicing
Here at Dual Mist Ltd, Stainless Steel 304 is used for many elements as this may be very sturdy and corrosion resistant compared to different similar metals. The physique is machined out of Brass CZ121, which arrives as massive bars of steel which are delivered to the warehouse in 3m lengths. This is then minimize into two smaller parts able to insert into the machine. Not all water mist companies have the power to machine the parts they require in-house though it might possibly show very useful for cost and production functions as we are about to see.
The metal is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine software is equipped with carbide tooling and high-pressure via coolant methods, with the twin-spindle and twin-turret making haste of the in any other case difficult 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, utterly automated – this means it could possibly turnover an unimaginable four,000 filters in a weekend fully unmanned.
The brass heads are additionally de-burred on the machine, eradicating all sharp edges before being polished and sent for Electroless Nickel Plating. This provides a corrosion-proof coating to the brass, enabling it to turn into much more sturdy. All elements are then inspected for dimensional accuracy before the assembly stage.
This Technifor Laser machine engraves every nozzle in preparation for the testing stages.
There are many small elements of various shapes and sizes that make up the nozzle – In the DM4R nozzle, (as seen on the leak-testing pic) there are a total of 13 elements or ‘components’. These elements are then meticulously put collectively and assembled by the manufacturing staff requiring a fair amount of labour earlier than the ultimate product is achieved. Various stages embrace tightening with specifically tailored instruments, urgent utilizing a hand-press and using a particular ‘Locktite’ formulation at some phases which is a threadlock that stops fixings from coming loose during the operational lifetime of the product. The ultimate stage of meeting is rigorously loading the bulb and making use of the proper load to it using a torque wrench.
The assembled nozzles are then positioned on one other machine to have the ability to be labelled and uniquely identified using a serial quantity. At Dual Mist Ltd that is carried out on a Technifor Laser Engraver fitted with a 4th axis unit earlier than they are ready to be positioned through the assorted phases of testing.
Cull Testing
Also often known as bubble testing in layman’s terms, this take a look at is to make sure no harm has occurred to the bulb throughout meeting 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 inserting in heat water to find a way to shrink the scale of the bubble to nothing. Once this is checked, the nozzles are then left to rest and return to room temperature earlier than the bubble is measured as soon as again in order to ensure it has returned to the unique measurement within a small tolerance.
Leak Testing
Every nozzle is also stringently examined 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 manufacturing line, however this is an especially important stage of the testing as leaks may occur if dust is trapped throughout the seal face.
Activation Testing
On a monthly basis, random nozzles are also examined for activation by inserting the nozzle on a pressure jig at numerous pressures and applying heat to the bulbs. The nozzles ought to all activate cleanly across the whole pressure range specified to that nozzle.
A member of the production group makes use of a microscope and software program to discover out the size of every bubble within the bulb.
At Dual Mist Ltd, these exams aren’t simply to guarantee the standard of the manufacturing line but are additionally an essential a part of the LPCB Approval. These approvals allow customers to recognise that the merchandise they’re shopping for are made to the best possible high quality standard within the area.
The drawback to this is that the Approval Testing system may be each costly and time-consuming – sometimes needing to be booked several months in advance and requiring years of hard work to achieve.
The nozzles produced by Dual Mist have been put by way of their paces at BRE Global by way of both fire testing and component/type approval.
Tamper proofing
In order to guarantee 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 pressure load setting on the bulb is then subsequently fixed.
The nozzles are then able to be packaged and despatched off for set up.
Here is เพรสเชอร์เกจวัดแรงดันน้ำ of a control panel having been installed in The Claridges Hotel, London, UK. This is the place the system is operated.
Rather than having to make use of the heavy and labour-intensive steel pipes typically utilized in high-pressure methods, low-pressure water systems can use CPVC piping. This is a particular kind of fire-resistant plastic enabling fast set up. Instead of threading every pipe, a heated glue can be used to quickly construct giant pipe networks. These networks are approved to handle up to 12 bar pressure. The nozzles are screwed into a particular pipe adaptor using a half-inch gas fitting.
An electric management panel is fitted for the system control together with pumps and a water tank, usually with a mains feed.
The system is tested, signed off and handed over to the shopper.
The ultimate product as quickly as installed. This reveals how we anticipate to see the nozzles as soon as a project has been completed.
As we can see there are many stages to go from metallic to nozzle head with each nozzle taking a significant effort by various professionals to complete to the permitted standard.
Not only do water mist nozzles require multiple phases of machining and assembling, they want to additionally endure a string of checks in order to be accredited for set up. Once put in, there are even additional checks undergone, generally by third-party organisations in order for the complete fireplace suppression system to lastly be handed over to the consumer.
Water mist expertise assures security, quality and assurance through the stringent testing that’s required.
With the current publication of water mist standards, notably in Britain over latest years, constructing developers can now be assured that the standard required for water mist techniques is now at an equivalent commonplace to other suppression systems.
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