Introducing water mist know-how – Part 2

Water mist technology continues to be a comparatively new idea by method of fire suppression, yet it’s proving to be an exciting growth within the trade. As the business evolves, so do the rules, laws and requirements in order to improve safety and allow development. These can vary largely from nation to country, and even region to area.
The method during which a water mist system operates is an analogous mechanism to the normal sprinkler system in that the nozzles are usually 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 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 lots of new projects/developments across a lot of the globe at present.
The metallic arrives for chopping

Here at Dual Mist Ltd, Stainless Steel 304 is used for so much of components as it is extremely durable and corrosion resistant compared to different comparable metals. The body is machined out of Brass CZ121, which arrives as massive bars of metal which are 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 ability to machine the elements they require in-house although it can prove very useful for cost and manufacturing functions as we’re 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 techniques, with the twin-spindle and twin-turret making haste of the otherwise complicated components. 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 fifty one seconds, fully automated – this means it might possibly turnover an unimaginable 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 supplies a corrosion-proof coating to the brass, enabling it to become far more durable. All elements are then inspected for dimensional accuracy earlier than the meeting stage.
This Technifor Laser machine engraves each nozzle in preparation for the testing levels.

There are many small elements of assorted 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 elements or ‘components’. These parts 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 levels embody tightening with specially tailored instruments, pressing utilizing a hand-press and using a particular ‘Locktite’ formulation at some phases which is a threadlock that stops fixings from coming loose during the operational lifetime of the product. The ultimate stage of meeting is carefully loading the bulb and making use of the proper load to it using a torque wrench.
The assembled nozzles are then positioned on another machine to have the ability 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 before they are able to be positioned by way of the varied levels of testing.
pressure gauge digital ราคา known as bubble testing in layman’s phrases, this check 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 using a high-powered microscope to measure the size of the bubble in each bulb before putting in warm water in order to shrink the dimensions 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 so as to ensure it has returned to the unique measurement inside a small tolerance.
Leak Testing

Every nozzle can be stringently examined for leaks by applying 24-bar pressure for 1 hour and ensuring no water has escaped. It is uncommon for any leaks on the production line, but that is an extremely important stage of the testing as leaks may happen if dirt is trapped throughout the seal face.
Activation Testing

On a month-to-month foundation, random nozzles are additionally tested for activation by placing the nozzle on a strain jig at various pressures and making use of warmth to the bulbs. The nozzles ought to all activate cleanly across the entire pressure range specified to that nozzle.
A member of the manufacturing staff makes use of a microscope and software program to determine the dimensions of each bubble within the bulb.

At Dual Mist Ltd, these tests are not just to assure the standard of the manufacturing line but are additionally an important a half of the LPCB Approval. These approvals enable prospects to recognise that the products they are shopping for are made to the highest potential quality normal in the area.
The drawback to this is that the Approval Testing system could be each expensive and time-consuming – generally needing to be booked several months prematurely and requiring years of exhausting work to attain.
The nozzles produced by Dual Mist have been put through their paces at BRE Global by means of each hearth testing and component/type approval.
Tamper proofing

In order to make certain that no one 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 fastened.
The nozzles are then ready to be packaged and despatched off for set up.
Here is an instance of a control panel having been put in in The Claridges Hotel, London, UK. This is the place the system is operated.

Rather than having to make use of the heavy and labour-intensive steel pipes typically utilized in high-pressure systems, low-pressure water techniques can use CPVC piping. This is a particular kind of fire-resistant plastic enabling fast set up. Instead of threading each pipe, a heated glue can be utilized to rapidly build giant pipe networks. These networks are approved to deal with as a lot as 12 bar pressure. The nozzles are screwed into a special pipe adaptor using a half-inch gas fitting.
An electrical control panel is fitted for the system management together with pumps and a water tank, often with a mains feed.
The system is examined, signed off and handed over to the client.
The ultimate product once put in. This exhibits how we anticipate to see the nozzles as quickly as a venture has been completed.

As we are able to see there are many stages to go from metal to nozzle head with each nozzle taking a significant effort by various professionals to finish to the accredited normal.
Not only do water mist nozzles require multiple stages of machining and assembling, they must additionally undergo a string of exams in order to be accredited for installation. Once installed, there are even additional exams undergone, sometimes by third-party organisations to guarantee that the entire fireplace suppression system to lastly be handed over to the shopper.
Water mist expertise assures safety, high quality and assurance via the stringent testing that is required.
With the recent publication of water mist standards, notably in Britain over latest years, constructing builders can now be assured that the standard required for water mist methods is now at an equal standard to different suppression techniques.
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