Introducing water mist expertise – Part 2

Water mist technology is still a comparatively new concept in phrases of fireplace suppression, but it’s proving to be an thrilling development within the industry. As the industry evolves, so do the laws, laws and requirements in order to enhance safety and enable growth. These can vary largely from nation to nation, and even area to area.
The way during which a water mist system operates is an identical mechanism to the standard sprinkler system in that the nozzles are usually activated via a bulb which blows at a specific temperature allowing for the activation of the mist through a low-pressure water piping system.
Here we take a look at how some water mist nozzles are produced and put in – from arriving as a big ‘bar’ of steel, to turning into the efficient water mist nozzles we see installed in plenty of new projects/developments throughout a lot of the globe at present.
The steel arrives for chopping
Here at Dual Mist Ltd, Stainless Steel 304 is used for many parts as this can be very durable and corrosion resistant in comparability to other comparable metals. The body is machined out of Brass CZ121, which arrives as large bars of metallic that are delivered to the warehouse in 3m lengths. This is then reduce into two smaller elements able to insert into the machine. Not all water mist companies have the ability to machine the components they require in-house though it could possibly show very beneficial for price and production functions as we are about to see.
The steel is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine tool is equipped with carbide tooling and high-pressure via coolant methods, with the twin-spindle and twin-turret making haste of the otherwise sophisticated elements. เกจแรงดัน Sliding Head Lathe is used for the smaller elements.
A Citizen L12 also makes the filters with a capability of drilling 365 holes in fifty one seconds, utterly automated – this means it could turnover an unbelievable 4,000 filters in a weekend fully 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 supplies a corrosion-proof coating to the brass, enabling it to turn out to be much more durable. All elements are then inspected for dimensional accuracy earlier than the assembly stage.
This Technifor Laser machine engraves each nozzle in preparation for the testing phases.
There are many small elements of various styles and sizes 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 collectively and assembled by the manufacturing team requiring a good quantity of labour before the final product is achieved. Various levels embody tightening with specifically tailored tools, urgent utilizing a hand-press and utilizing a particular ‘Locktite’ formula at some stages which is a threadlock that forestalls fixings from coming free through the operational lifetime of the product. The final stage of meeting is rigorously loading the bulb and applying the correct load to it using a torque wrench.
The assembled nozzles are then positioned on another machine to find a way to be labelled and uniquely identified utilizing a serial quantity. At Dual Mist Ltd this is carried out on a Technifor Laser Engraver fitted with a 4th axis unit earlier than they are able to be placed by way of the various stages of testing.
Cull Testing
Also known as bubble testing in layman’s terms, this check is to ensure no harm has occurred to the bulb during assembly and is a crucial test for LPCB approval. The take a look at includes using a high-powered microscope to measure the size of the bubble in every bulb before inserting in warm water in order to shrink the scale of the bubble to nothing. Once that is checked, the nozzles are then left to rest and return to room temperature before the bubble is measured as quickly as again to have the ability to guarantee it has returned to the unique dimension inside a small tolerance.
Leak Testing
Every nozzle can additionally be stringently tested for leaks by making use of 24-bar stress for 1 hour and ensuring no water has escaped. It is rare for any leaks on the manufacturing line, however that is an extremely very important stage of the testing as leaks could happen if filth is trapped inside the seal face.
Activation Testing
On a monthly foundation, random nozzles are also examined for activation by inserting the nozzle on a stress jig at numerous pressures and making use of warmth to the bulbs. The nozzles should all activate cleanly throughout the entire stress range specified to that nozzle.
A member of the manufacturing team uses a microscope and software program to determine the scale of every bubble in the bulb.
At Dual Mist Ltd, these exams aren’t simply to assure the standard of the manufacturing line but are also an important a part of the LPCB Approval. These approvals enable clients to recognise that the merchandise they are buying are made to the best possible high quality commonplace within the region.
The drawback to this is that the Approval Testing system could be both costly and time-consuming – generally needing to be booked a number of months prematurely and requiring years of onerous work to attain.
The nozzles produced by Dual Mist have been put through their paces at BRE Global in phrases of both fireplace testing and component/type approval.
Tamper proofing
In order to ensure 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 fixed.
The nozzles are then able to be packaged and sent off for installation.
Here is an instance 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 often utilized in high-pressure methods, low-pressure water techniques can use CPVC piping. This is a special kind of fire-resistant plastic enabling quick installation. Instead of threading every pipe, a heated glue can be utilized to shortly construct large pipe networks. These networks are accredited to deal with as much as 12 bar strain. The nozzles are screwed right into a particular pipe adaptor utilizing a half-inch fuel fitting.
An electric control panel is fitted for the system control along with pumps and a water tank, normally with a mains feed.
The system is tested, signed off and handed over to the shopper.
The final product as soon as installed. This exhibits how we anticipate to see the nozzles as soon as a challenge has been accomplished.
As we can see there are numerous stages to go from steel to nozzle head with each nozzle taking a big effort by various professionals to complete to the permitted standard.
Not only do water mist nozzles require a number of levels of machining and assembling, they want to additionally undergo a string of tests to have the ability to be approved for installation. Once installed, there are even further checks undergone, generally by third-party organisations to ensure that the whole fire suppression system to lastly be handed over to the consumer.
Water mist know-how assures safety, quality and assurance by way of the stringent testing that is required.
With the latest publication of water mist requirements, significantly in Britain over latest years, building builders can now be assured that the standard required for water mist systems is now at an equivalent standard to other suppression systems.
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