Introducing water mist technology – Part 2

Water mist know-how continues to be a comparatively new concept in phrases of fireplace suppression, but it is proving to be an thrilling development in the business. As the business evolves, so do the rules, laws and necessities in order to improve safety and enable growth. These can vary largely from country to country, and even region to area.
The way during which a water mist system operates is a similar mechanism to the standard sprinkler system in that the nozzles are often activated through a bulb which blows at a specific temperature permitting 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 put in – from arriving as a big ‘bar’ of metallic, to becoming the environment friendly water mist nozzles we see installed in many new projects/developments throughout a lot of the globe today.
The metallic arrives for chopping
Here at Dual Mist Ltd, Stainless Steel 304 is used for many components as it is extremely durable and corrosion resistant compared to different comparable metals. The physique is machined out of Brass CZ121, which arrives as large bars of metallic which are delivered to the warehouse in 3m lengths. This is then minimize into two smaller elements able to insert into the machine. Not all water mist companies have the flexibility to machine the parts they require in-house though it can prove very beneficial for value and production functions as we are about to see.
The metal is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine tool is provided with carbide tooling and high-pressure via coolant systems, with the twin-spindle and twin-turret making haste of the in any other case difficult parts. เกจวัดแรงดันสูง Sliding Head Lathe is used for the smaller parts.
A Citizen L12 additionally makes the filters with a functionality of drilling 365 holes in 51 seconds, fully automated – this implies it could turnover an unimaginable 4,000 filters in a weekend fully unmanned.
The brass heads are also de-burred on the machine, removing all sharp edges earlier than 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 sturdy. All components are then inspected for dimensional accuracy earlier than the meeting stage.
This Technifor Laser machine engraves every nozzle in preparation for the testing phases.
There are many small parts of varied sizes and shapes that make up the nozzle – In the DM4R nozzle, (as seen on the leak-testing pic) there are a complete of 13 components or ‘components’. These components are then meticulously put together and assembled by the production group requiring a good quantity of labour before the final product is achieved. Various phases include tightening with specifically tailored instruments, pressing utilizing a hand-press and utilizing a specific ‘Locktite’ formula at some phases which is a threadlock that stops fixings from coming unfastened through the operational lifetime of the product. The last stage of assembly is fastidiously loading the bulb and applying the proper load to it utilizing a torque wrench.
The assembled nozzles are then placed on one other machine so as to be labelled and uniquely identified using a serial number. At Dual Mist Ltd that is accomplished on a Technifor Laser Engraver fitted with a 4th axis unit before they’re ready to be placed by way of the various phases of testing.
Cull Testing
Also known as bubble testing in layman’s phrases, this check is to make sure no harm has occurred to the bulb during meeting and is a critical check for LPCB approval. The test involves using a high-powered microscope to measure the size of the bubble in every bulb earlier than putting in heat water to be able 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 earlier than the bubble is measured once once more in order to ensure it has returned to the original measurement inside a small tolerance.
Leak Testing
Every nozzle is also stringently tested for leaks by applying 24-bar strain for 1 hour and guaranteeing no water has escaped. It is uncommon for any leaks on the manufacturing line, however this is an extremely important stage of the testing as leaks could occur if dust is trapped within the seal face.
Activation Testing
On a month-to-month basis, random nozzles are also examined for activation by putting the nozzle on a strain jig at varied pressures and applying warmth to the bulbs. The nozzles should all activate cleanly throughout the complete strain vary specified to that nozzle.
A member of the manufacturing group uses a microscope and software program to discover out the dimensions of every bubble in the bulb.
At Dual Mist Ltd, these exams are not just to guarantee the quality of the manufacturing line however are additionally an essential part of the LPCB Approval. These approvals allow customers to recognise that the merchandise they’re buying are made to the very best possible quality standard in the region.
The drawback to that is that the Approval Testing system can be each pricey and time-consuming – typically needing to be booked a quantity of months in advance and requiring years of onerous work to realize.
The nozzles produced by Dual Mist have been put by way of their paces at BRE Global in terms of each hearth testing and component/type approval.
Tamper proofing
In order to ensure that no one 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 mounted.
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 metal pipes typically utilized in high-pressure systems, low-pressure water methods can use CPVC piping. This is a special sort of fire-resistant plastic enabling quick installation. Instead of threading each pipe, a heated glue can be utilized to quickly construct giant pipe networks. These networks are permitted to handle as much as 12 bar strain. The nozzles are screwed into a particular pipe adaptor utilizing a half-inch gasoline becoming.
An electric control panel is fitted for the system management along with pumps and a water tank, often with a mains feed.
The system is tested, signed off and handed over to the consumer.
The final product once put in. This exhibits how we expect to see the nozzles as quickly as a project has been accomplished.
As we are ready to see there are numerous stages to go from metallic to nozzle head with each nozzle taking a significant effort by various professionals to finish to the permitted commonplace.
Not only do water mist nozzles require a number of stages of machining and assembling, they need to also bear a string of exams so as to be permitted for installation. Once put in, there are even additional tests undergone, typically by third-party organisations to guarantee that the entire fire suppression system to finally be handed over to the client.
Water mist technology assures security, high quality and assurance through 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 techniques is now at an equivalent normal to different suppression techniques.
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