Introducing water mist know-how – Part 2

Water mist technology continues to be a comparatively new concept in terms of fireplace suppression, but it is proving to be an thrilling growth in the industry. As เกจวัดแรงดัน250bar evolves, so do the regulations, laws and necessities in order to enhance safety and allow improvement. These can vary largely from country to nation, and even area to area.
The method in which a water mist system operates is an identical mechanism to the traditional sprinkler system in that the nozzles are often activated via a bulb which blows at a particular 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 large ‘bar’ of metal, to becoming the efficient water mist nozzles we see put in in many new projects/developments across a lot of the globe right now.
The metal arrives for chopping
Here at Dual Mist Ltd, Stainless Steel 304 is used for many components as it is extremely sturdy and corrosion resistant in comparability to other comparable metals. The body is machined out of Brass CZ121, which arrives as large bars of metal 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 corporations have the power to machine the components they require in-house though it can prove very useful for value and manufacturing functions as we are about to see.
The metal is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine software is supplied with carbide tooling and high-pressure via coolant techniques, with the twin-spindle and twin-turret making haste of the otherwise difficult components. A Citizen M532 Sliding Head Lathe is used for the smaller components.
A Citizen L12 additionally makes the filters with a functionality of drilling 365 holes in fifty one seconds, fully automated – this implies 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 before being polished and sent for Electroless Nickel Plating. This provides a corrosion-proof coating to the brass, enabling it to turn out to be far 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 stages.
There are many small elements of various sizes and shapes 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 components are then meticulously put together and assembled by the production group requiring a good quantity of labour earlier than the ultimate product is achieved. Various phases embrace tightening with specifically adapted tools, pressing utilizing a hand-press and utilizing a selected ‘Locktite’ formula at some phases which is a threadlock that prevents fixings from coming loose through the operational lifetime of the product. The final stage of assembly is rigorously loading the bulb and applying the right load to it utilizing a torque wrench.
The assembled nozzles are then positioned on another machine in order to be labelled and uniquely identified using a serial quantity. At Dual Mist Ltd this is accomplished on a Technifor Laser Engraver fitted with a 4th axis unit earlier than they are able to be positioned by way of the assorted phases of testing.
Cull Testing
Also known as bubble testing in layman’s terms, this check is to make sure no damage has occurred to the bulb during assembly and is a crucial test for LPCB approval. The check includes using a high-powered microscope to measure the scale of the bubble in every bulb earlier than placing in heat water in order 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 guarantee it has returned to the unique size within a small tolerance.
Leak Testing
Every nozzle is also stringently tested for leaks by applying 24-bar pressure for 1 hour and making certain no water has escaped. It is uncommon for any leaks on the manufacturing line, but that is an especially very important stage of the testing as leaks may occur if dust is trapped within the seal face.
Activation Testing
On a month-to-month basis, random nozzles are also tested for activation by inserting the nozzle on a strain jig at numerous pressures and applying heat to the bulbs. The nozzles should all activate cleanly across the complete pressure range specified to that nozzle.
A member of the production staff uses a microscope and software to find out the dimensions of every bubble within the bulb.
At Dual Mist Ltd, these checks are not just to assure the standard of the production line but are additionally an necessary a half of the LPCB Approval. These approvals allow prospects to recognise that the products they’re shopping for are made to the best potential quality commonplace in the region.
The drawback to that 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 exhausting work to attain.
The nozzles produced by Dual Mist have been put through their paces at BRE Global by way of each hearth testing and component/type approval.
Tamper proofing
In order to make sure that no person is tempted to intrude 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 sent off for installation.
Here is an example 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 use the heavy and labour-intensive metallic pipes typically utilized in high-pressure methods, low-pressure water systems can use CPVC piping. This is a particular type of fire-resistant plastic enabling quick installation. Instead of threading each pipe, a heated glue can be used to shortly build giant pipe networks. These networks are accredited to deal with up to 12 bar strain. The nozzles are screwed into a special pipe adaptor utilizing a half-inch gas fitting.
An electric management panel is fitted for the system control along with pumps and a water tank, usually with a mains feed.
The system is examined, signed off and handed over to the consumer.
The ultimate product once installed. This reveals how we anticipate to see the nozzles once a venture has been accomplished.
As we will see there are many stages to go from metallic to nozzle head with each nozzle taking a major effort by various professionals to complete to the approved normal.
Not only do water mist nozzles require a number of phases of machining and assembling, they want to additionally undergo a string of exams to be able to be approved for installation. Once installed, there are even further tests undergone, sometimes by third-party organisations in order for the entire fire suppression system to finally be handed over to the consumer.
Water mist expertise assures security, quality and assurance by way of the stringent testing that’s required.
With the current publication of water mist standards, significantly in Britain over recent years, building builders can now be assured that the quality required for water mist techniques is now at an equal commonplace to other suppression techniques.
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