Introducing water mist know-how – Part 2

Water mist know-how continues to be a relatively new concept by way of hearth suppression, but it is proving to be an thrilling growth in the business. As the business evolves, so do the rules, legal guidelines and necessities so as to enhance security and enable growth. These can range largely from nation to country, and even region to region.
The way by which a water mist system operates is an analogous mechanism to the standard sprinkler system in that the nozzles are normally activated through a bulb which blows at a specific temperature allowing for the activation of the mist by way of a low-pressure water piping system.
Here we take a look at how some water mist nozzles are produced and installed – from arriving as a big ‘bar’ of metal, to changing into the efficient water mist nozzles we see installed in plenty of new projects/developments throughout much of the globe today.
The metal arrives for cutting
Here at Dual Mist Ltd, Stainless Steel 304 is used for many components as it is extremely durable and corrosion resistant compared to other similar metals. The body is machined out of Brass CZ121, which arrives as large bars of steel which may be delivered to the warehouse in 3m lengths. This is then cut into two smaller components able to insert into the machine. Not all water mist corporations have the flexibility to machine the elements they require in-house though it could show very helpful for cost and production functions as we are about to see.
เกจวัดแรงดันpcp is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine device is supplied with carbide tooling and high-pressure through coolant methods, with the twin-spindle and twin-turret making haste of the in any other case sophisticated parts. 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 possibly turnover an incredible four,000 filters in a weekend fully unmanned.
The brass heads are also de-burred on the machine, eradicating all sharp edges earlier than being polished and despatched for Electroless Nickel Plating. This offers a corrosion-proof coating to the brass, enabling it to become rather more durable. All elements are then inspected for dimensional accuracy before the assembly stage.
This Technifor Laser machine engraves every nozzle in preparation for the testing stages.
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 13 parts or ‘components’. These components are then meticulously put collectively and assembled by the production staff requiring a good amount of labour earlier than the ultimate product is achieved. Various phases include tightening with specifically adapted tools, pressing using a hand-press and using a particular ‘Locktite’ method at some stages which is a threadlock that forestalls fixings from coming loose through the operational lifetime of the product. The final stage of meeting is rigorously loading the bulb and making use of the right load to it using a torque wrench.
The assembled nozzles are then positioned on another machine in order to be labelled and uniquely identified utilizing a serial number. At Dual Mist Ltd this is done on a Technifor Laser Engraver fitted with a 4th axis unit before they’re able to be positioned via the assorted levels of testing.
Cull Testing
Also often identified 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 critical take a look at for LPCB approval. The check entails using a high-powered microscope to measure the scale of the bubble in every bulb before putting in heat water to have the ability 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 earlier than the bubble is measured as soon as again so as to ensure it has returned to the unique measurement inside a small tolerance.
Leak Testing
Every nozzle is also stringently examined for leaks by applying 24-bar stress for 1 hour and making certain no water has escaped. It is uncommon for any leaks on the manufacturing line, however that is an especially important stage of the testing as leaks may happen if dust is trapped within the seal face.
Activation Testing
On a month-to-month foundation, random nozzles are also examined for activation by inserting the nozzle on a strain jig at varied pressures and applying heat to the bulbs. The nozzles ought to all activate cleanly throughout the complete pressure range specified to that nozzle.
A member of the manufacturing staff uses a microscope and software program to determine the size of every bubble within the bulb.
At Dual Mist Ltd, these exams aren’t just to guarantee the standard of the manufacturing line however are additionally an necessary part of the LPCB Approval. These approvals allow clients to recognise that the products they’re shopping for are made to the highest potential high quality commonplace within the region.
The drawback to this is that the Approval Testing system may be each expensive and time-consuming – typically needing to be booked several months in advance and requiring years of hard work to attain.
The nozzles produced by Dual Mist have been put through their paces at BRE Global by way of both fire testing and component/type approval.
Tamper proofing
In order to ensure that no person 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 installation.
Here is an instance of a management panel having been installed in The Claridges Hotel, London, UK. This is where the system is operated.
Rather than having to make use of the heavy and labour-intensive steel pipes typically utilized in high-pressure methods, low-pressure water methods can use CPVC piping. This is a particular sort of fire-resistant plastic enabling quick installation. Instead of threading every pipe, a heated glue can be utilized to rapidly construct giant pipe networks. These networks are permitted to handle as much as 12 bar pressure. The nozzles are screwed into a particular pipe adaptor using a half-inch gasoline becoming.
An electrical management panel is fitted for the system control along with pumps and a water tank, normally with a mains feed.
The system is examined, signed off and handed over to the shopper.
The final product once installed. This exhibits how we expect to see the nozzles as soon as a venture has been completed.
As we are in a position to see there are many phases to go from steel to nozzle head with every nozzle taking a major effort by numerous professionals to finish to the accredited commonplace.
Not only do water mist nozzles require a quantity of levels of machining and assembling, they must additionally undergo a string of checks in order to be approved for set up. Once installed, there are even additional exams undergone, generally by third-party organisations to ensure that the complete hearth suppression system to finally be handed over to the client.
Water mist expertise assures security, quality and assurance through the stringent testing that’s required.
With the current publication of water mist standards, significantly in Britain over latest years, building builders can now be assured that the quality required for water mist systems is now at an equal standard to different suppression techniques.
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