Introducing water mist know-how – Part 2

Water mist know-how continues to be a relatively new concept in phrases of fireplace suppression, yet it’s proving to be an thrilling development in the business. As the trade evolves, so do the laws, laws and requirements to have the ability to enhance safety and enable development. These can differ largely from country to nation, and even area to region.
The means during which a water mist system operates is an analogous mechanism to the normal sprinkler system in that the nozzles are often activated via a bulb which blows at a particular temperature allowing 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 installed – from arriving as a large ‘bar’ of metallic, to turning into the environment friendly water mist nozzles we see installed in many new projects/developments across much of the globe right now.
The metallic arrives for cutting
Here at Dual Mist Ltd, Stainless Steel 304 is used for so much of components as it is extremely sturdy and corrosion resistant compared to other comparable metals. The physique is machined out of Brass CZ121, which arrives as large bars of steel that are delivered to the warehouse in 3m lengths. This is then reduce into two smaller parts able to insert into the machine. Not all water mist firms have the ability to machine the components they require in-house though it can show very helpful for cost and manufacturing purposes as we’re about to see.
The steel is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine device is equipped with carbide tooling and high-pressure by way of coolant techniques, with the twin-spindle and twin-turret making haste of the in any other case difficult components. A Citizen M532 Sliding Head Lathe is used for the smaller components.
A Citizen L12 also makes the filters with a capability of drilling 365 holes in fifty one seconds, utterly 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 before being polished and despatched for Electroless Nickel Plating. This offers a corrosion-proof coating to the brass, enabling it to turn out to be much more sturdy. All elements are then inspected for dimensional accuracy earlier than the assembly stage.
This Technifor Laser machine engraves every nozzle in preparation for the testing phases.
There are many small components of varied sizes and shapes that make up the nozzle – In the DM4R nozzle, (as seen on the leak-testing pic) there are a complete of 13 elements or ‘components’. เกจวัดแรงดันน้ำมันเครื่อง are then meticulously put collectively and assembled by the manufacturing staff requiring a fair amount of labour earlier than the final product is achieved. Various levels embrace tightening with specifically tailored instruments, pressing using a hand-press and using a specific ‘Locktite’ method at some levels which is a threadlock that forestalls fixings from coming loose in the course of the operational lifetime of the product. The final stage of meeting is rigorously loading the bulb and applying the proper load to it utilizing a torque wrench.
The assembled nozzles are then placed on one other machine so as to be labelled and uniquely recognized using a serial quantity. At Dual Mist Ltd this is done on a Technifor Laser Engraver fitted with a 4th axis unit before they’re ready to be positioned by way of the various levels of testing.
Cull Testing
Also generally known as bubble testing in layman’s terms, this take a look at is to ensure no injury has occurred to the bulb throughout meeting and is a critical check for LPCB approval. The test involves utilizing a high-powered microscope to measure the size of the bubble in each bulb earlier than inserting in warm water in order to shrink the dimensions of the bubble to nothing. Once this is checked, the nozzles are then left to relaxation and return to room temperature before the bubble is measured as soon as again in order to guarantee it has returned to the unique dimension within a small tolerance.
Leak Testing
Every nozzle is also stringently examined for leaks by making use of 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 a particularly vital stage of the testing as leaks could happen if dirt is trapped throughout the seal face.
Activation Testing
On a monthly basis, random nozzles are also tested for activation by putting the nozzle on a pressure jig at numerous pressures and applying warmth to the bulbs. The nozzles should all activate cleanly across the complete pressure vary specified to that nozzle.
A member of the manufacturing team makes use of a microscope and software program to find out the size of each bubble in the bulb.
At Dual Mist Ltd, these tests usually are not simply to assure the quality of the production line however are additionally an essential a part of the LPCB Approval. These approvals enable customers to recognise that the merchandise they are buying are made to the very best attainable quality standard within the area.
The disadvantage to this is that the Approval Testing system may be both costly and time-consuming – generally needing to be booked a quantity of months upfront and requiring years of onerous work to attain.
The nozzles produced by Dual Mist have been put by way of their paces at BRE Global by means of each fire testing and component/type approval.
Tamper proofing
In order to make certain that nobody 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 mounted.
The nozzles are then ready to be packaged and despatched off for set up.
Here is an instance of a control panel having been put in in The Claridges Hotel, London, UK. This is the place the system is operated.
เกจวัดแรงดันไนโตรเจนราคา than having to make use of the heavy and labour-intensive steel pipes usually utilized in high-pressure methods, low-pressure water techniques can use CPVC piping. This is a particular type of fire-resistant plastic enabling fast set up. Instead of threading each pipe, a heated glue can be used to quickly build giant pipe networks. These networks are permitted to handle up to 12 bar stress. The nozzles are screwed right into a particular pipe adaptor using a half-inch fuel fitting.
An electric management panel is fitted for the system management along with pumps and a water tank, normally with a mains feed.
The system is tested, signed off and handed over to the consumer.
The ultimate product once put in. This shows how we count on to see the nozzles as quickly as a project has been accomplished.
As we are able to see there are numerous phases to go from metal to nozzle head with every nozzle taking a big effort by varied professionals to finish to the approved standard.
Not only do water mist nozzles require multiple levels of machining and assembling, they must additionally endure a string of checks in order to be approved for installation. Once installed, there are even further exams undergone, generally by third-party organisations to ensure that the whole fire suppression system to lastly be handed over to the client.
Water mist technology assures safety, high quality and assurance through the stringent testing that’s required.
With the recent publication of water mist requirements, significantly in Britain over current years, building developers can now be assured that the standard required for water mist techniques is now at an equal normal to other suppression methods.
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