Introducing water mist expertise – Part 2

Water mist technology remains to be a relatively new concept by means of hearth suppression, but it is proving to be an exciting growth within the trade. As the trade evolves, so do the regulations, legal guidelines and requirements so as to improve safety and allow improvement. These can differ largely from nation to nation, and even region to area.
The means by which a water mist system operates is an analogous mechanism to the traditional sprinkler system in that the nozzles are often activated through a bulb which blows at a selected temperature permitting 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 metallic, to changing into the efficient water mist nozzles we see put in in many new projects/developments throughout much of the globe today.
The metal arrives for chopping
Here at Dual Mist Ltd, Stainless Steel 304 is used for lots of elements as this can be very durable and corrosion resistant compared to different comparable metals. The body is machined out of Brass CZ121, which arrives as giant bars of metal which are delivered to the warehouse in 3m lengths. This is then cut into two smaller elements able to insert into the machine. Not all water mist firms have the power to machine the parts they require in-house although it can show very helpful for cost 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 supplied with carbide tooling and high-pressure by way of coolant methods, with the twin-spindle and twin-turret making haste of the otherwise complicated elements. 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 51 seconds, completely automated – this implies it can turnover an incredible 4,000 filters in a weekend fully unmanned.
ราคาเกจวัดแรงดันน้ำ are also de-burred on the machine, eradicating all sharp edges before being polished and despatched for Electroless Nickel Plating. This provides a corrosion-proof coating to the brass, enabling it to turn into rather more durable. All components 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 components of assorted shapes 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 components are then meticulously put collectively and assembled by the production staff requiring a fair quantity of labour before the final product is achieved. Various phases embody tightening with specifically tailored instruments, pressing using a hand-press and utilizing a selected ‘Locktite’ method at some levels which is a threadlock that prevents fixings from coming unfastened through the operational lifetime of the product. The ultimate stage of assembly 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 one other machine so as to be labelled and uniquely identified utilizing a serial quantity. At Dual Mist Ltd that is done on a Technifor Laser Engraver fitted with a 4th axis unit earlier than they are able to be positioned by way of the varied stages of testing.
Cull Testing
Also generally recognized as bubble testing in layman’s terms, this test is to ensure no damage has occurred to the bulb during meeting and is a important take a look at for LPCB approval. The take a look at entails utilizing a high-powered microscope to measure the dimensions of the bubble in each bulb earlier than placing in warm water so as to shrink the scale 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 once again in order to guarantee it has returned to the original dimension within a small tolerance.
Leak Testing
Every nozzle can also be stringently examined for leaks by applying 24-bar pressure for 1 hour and ensuring no water has escaped. It is rare for any leaks on the production line, however this is an especially important stage of the testing as leaks may occur if dust is trapped within the seal face.
Activation Testing
On a month-to-month foundation, random nozzles are also examined for activation by placing the nozzle on a stress jig at numerous pressures and applying heat to the bulbs. The nozzles should all activate cleanly throughout the entire pressure range specified to that nozzle.
A member of the production group uses a microscope and software to determine the scale of each bubble in the bulb.
At Dual Mist Ltd, these tests aren’t simply to guarantee the quality of the production line but are also an important a half of the LPCB Approval. These approvals enable customers to recognise that the products they are shopping for are made to the best attainable quality commonplace in the region.
The drawback to that is that the Approval Testing system could be both expensive 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 via their paces at BRE Global when it comes to both fireplace testing and component/type approval.
Tamper proofing
In order to guarantee that nobody is tempted to intervene 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 fixed.
The nozzles are then able to be packaged and despatched off for set up.
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 usually used in high-pressure methods, low-pressure water methods 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 shortly build massive pipe networks. These networks are accredited to handle as a lot as 12 bar pressure. The nozzles are screwed into a particular pipe adaptor using a half-inch gasoline fitting.
An electrical control panel is fitted for the system control together with pumps and a water tank, often with a mains feed.
The system is examined, signed off and handed over to the shopper.
The last product as soon as put in. This reveals how we count on to see the nozzles once a project has been completed.
As we are ready to see there are many phases to go from steel to nozzle head with every nozzle taking a major effort by varied professionals to complete to the accredited standard.
Not solely do water mist nozzles require a quantity of phases of machining and assembling, they must also undergo a string of tests to be able to be approved for set up. Once put in, there are even further exams undergone, generally by third-party organisations to guarantee that the entire hearth suppression system to finally be handed over to the consumer.
Water mist know-how assures security, high quality and assurance through the stringent testing that’s required.
With the recent publication of water mist requirements, notably in Britain over current years, constructing developers can now be assured that the quality required for water mist methods is now at an equal normal to different suppression techniques.
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