Introducing water mist technology – Part 2

Water mist technology is still a relatively new idea when it comes to fireplace suppression, but it is proving to be an exciting improvement in the trade. As the industry evolves, so do the laws, laws and requirements to be able to improve safety and allow improvement. These can differ largely from nation to nation, and even area to region.
The means during which a water mist system operates is an identical mechanism to the standard sprinkler system in that the nozzles are often activated via a bulb which blows at a specific 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 installed – from arriving as a big ‘bar’ of metallic, to becoming the environment friendly water mist nozzles we see installed in plenty of new projects/developments across a lot of the globe right now.
The metallic arrives for slicing
Here at Dual Mist Ltd, Stainless Steel 304 is used for so much of parts as it is extremely sturdy and corrosion resistant in comparison to different related metals. The body is machined out of Brass CZ121, which arrives as large bars of steel which are delivered to the warehouse in 3m lengths. This is then cut into two smaller parts ready 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 helpful 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 device is provided with carbide tooling and high-pressure by way of coolant techniques, 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 can turnover an unbelievable 4,000 filters in a weekend fully unmanned.
The brass heads are additionally de-burred on the machine, removing all sharp edges earlier than being polished and despatched for Electroless Nickel Plating. This provides a corrosion-proof coating to the brass, enabling it to become rather more sturdy. All parts are then inspected for dimensional accuracy earlier than the meeting stage.
This Technifor Laser machine engraves every nozzle in preparation for the testing phases.
There are many small parts 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 components or ‘components’. These parts are then meticulously put together and assembled by the production group requiring a fair quantity of labour before the ultimate product is achieved. Various phases include tightening with specifically tailored tools, pressing utilizing a hand-press and utilizing a selected ‘Locktite’ formula at some phases which is a threadlock that forestalls fixings from coming free in the course of the operational lifetime of the product. The final stage of meeting 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 to be able to be labelled and uniquely recognized using a serial quantity. At Dual Mist Ltd that is carried out on a Technifor Laser Engraver fitted with a 4th axis unit before they are able to be placed through the assorted phases of testing.
Cull Testing
Also known as bubble testing in layman’s phrases, this check is to make sure no damage has occurred to the bulb throughout assembly and is a crucial test for LPCB approval. The take a look at includes utilizing a high-powered microscope to measure the scale of the bubble in every bulb earlier than putting in warm water so as to shrink the size of the bubble to nothing. Once that is checked, the nozzles are then left to rest and return to room temperature earlier than the bubble is measured as soon as once more to find a way to ensure it has returned to the unique measurement within 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 rare for any leaks on the production line, however this is an extremely vital stage of the testing as leaks could occur if filth is trapped inside the seal face.
Activation Testing
On a monthly basis, random nozzles are also examined for activation by placing the nozzle on a strain jig at varied pressures and applying warmth to the bulbs. The nozzles should all activate cleanly across the whole stress range specified to that nozzle.
A member of the production group makes use of a microscope and software to find out the dimensions of each bubble in the bulb.
At Dual Mist Ltd, these exams usually are not simply to assure the quality of the manufacturing line however are also an essential part of the LPCB Approval. These approvals enable clients to recognise that the products they are shopping for are made to the highest attainable quality normal in the area.
เพรสเชอร์เกจวัดแรงดันน้ำ to this is that the Approval Testing system may be each expensive and time-consuming – typically needing to be booked several months prematurely and requiring years of hard work to realize.
The nozzles produced by Dual Mist have been put by way of their paces at BRE Global in terms of both hearth testing and component/type approval.
Tamper proofing
In order to make sure that nobody is tempted to interfere with the grub screw holding the bulb, a small plastic bung is pressed into the grub screw. The stress load setting on the bulb is then subsequently fastened.
The nozzles are then able to be packaged and despatched off for installation.
Here is an example of a management panel having been put in in The Claridges Hotel, London, UK. This is the place the system is operated.
Rather than having to use the heavy and labour-intensive metal pipes usually utilized in high-pressure methods, low-pressure water systems can use CPVC piping. This is a particular sort of fire-resistant plastic enabling fast set up. Instead of threading every pipe, a heated glue can be used to rapidly construct giant pipe networks. These networks are accredited to handle as much as 12 bar stress. The nozzles are screwed into a particular pipe adaptor utilizing a half-inch gasoline fitting.
An electric control panel is fitted for the system control together with pumps and a water tank, often with a mains feed.
The system is tested, signed off and handed over to the consumer.
The ultimate product once put in. This reveals how we count on to see the nozzles once a venture has been accomplished.
As we are in a position to see there are numerous levels to go from metallic to nozzle head with every nozzle taking a significant effort by various professionals to finish to the approved normal.
Not solely do water mist nozzles require a number of stages of machining and assembling, they want to additionally endure a string of exams to be able to be accredited for set up. Once put in, there are even additional checks undergone, typically by third-party organisations to ensure that the entire fireplace suppression system to finally be handed over to the consumer.
Water mist know-how assures safety, high quality and assurance by way of the stringent testing that is required.
With the current publication of water mist requirements, particularly in Britain over current years, building builders can now be assured that the quality required for water mist methods is now at an equivalent standard to different suppression systems.
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