Introducing water mist expertise – Part 2

Water mist know-how continues to be a comparatively new idea in terms of fireplace suppression, but it is proving to be an exciting growth in the business. As the trade evolves, so do the laws, laws and necessities in order to enhance security and allow growth. These can differ largely from nation to nation, and even area to region.
The way in which a water mist system operates is an analogous 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 via a low-pressure water piping system.
Here we have a look at how some water mist nozzles are produced and installed – from arriving as a large ‘bar’ of steel, to changing into the environment friendly water mist nozzles we see installed in many new projects/developments throughout much of the globe today.
The metallic arrives for slicing
Here at Dual Mist Ltd, Stainless Steel 304 is used for a lot of elements as it is extremely sturdy and corrosion resistant compared to other comparable metals. The body is machined out of Brass CZ121, which arrives as massive bars of metallic which would possibly be 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 parts they require in-house although it could possibly show very useful for value and production functions as we’re about to see.
The steel is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine software is provided 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 capability of drilling 365 holes in 51 seconds, completely automated – this means it could turnover an unimaginable four,000 filters in a weekend completely unmanned.
The brass heads are additionally de-burred on the machine, eradicating all sharp edges before being polished and despatched for Electroless Nickel Plating. This offers a corrosion-proof coating to the brass, enabling it to become far more sturdy. 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 stages.
There are many small parts of assorted styles and sizes 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 collectively and assembled by the production group requiring a good quantity of labour earlier than the final product is achieved. Various stages embody tightening with specially tailored tools, urgent utilizing a hand-press and utilizing a selected ‘Locktite’ formulation at some phases which is a threadlock that stops fixings from coming loose in the course of the operational lifetime of the product. เกจวัดแรงดันถังแก๊ส of meeting is fastidiously loading the bulb and making use of 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 recognized using a serial quantity. At Dual Mist Ltd this is carried out on a Technifor Laser Engraver fitted with a 4th axis unit before they’re able to be placed by way of the assorted stages of testing.
Cull Testing
Also generally identified as bubble testing in layman’s terms, this test is to ensure no injury has occurred to the bulb during meeting and is a important check for LPCB approval. The test involves using a high-powered microscope to measure the size of the bubble in each bulb before placing in heat water in order to shrink the scale of the bubble to nothing. Once that is checked, the nozzles are then left to relaxation and return to room temperature before the bubble is measured as quickly as once more in order to guarantee it has returned to the original dimension within a small tolerance.
Leak Testing
Every nozzle can be 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 production line, but that is an especially very important stage of the testing as leaks could happen if dirt is trapped throughout the seal face.
Activation Testing
On a month-to-month foundation, random nozzles are also tested for activation by inserting the nozzle on a stress jig at varied pressures and applying warmth to the bulbs. The nozzles ought to all activate cleanly across the complete strain range specified to that nozzle.
A member of the manufacturing staff makes use of a microscope and software program to determine the scale of each bubble within the bulb.
At Dual Mist Ltd, these exams aren’t simply to assure the standard of the manufacturing line but are also an essential part of the LPCB Approval. These approvals allow prospects to recognise that the merchandise they are buying are made to the very best potential quality commonplace within the region.
The drawback to that is that the Approval Testing system could be both costly and time-consuming – typically 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 when it comes to both hearth testing and component/type approval.
Tamper proofing
In order to ensure that no person 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 fixed.
The nozzles are then ready to be packaged and sent off for installation.
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 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 fast set up. Instead of threading every pipe, a heated glue can be used to rapidly build giant pipe networks. These networks are accredited to deal with up to 12 bar pressure. The nozzles are screwed right into a particular pipe adaptor using a half-inch gas fitting.
An electric management panel is fitted for the system management along with pumps and a water tank, usually with a mains feed.
The system is tested, signed off and handed over to the shopper.
The final product once installed. This reveals how we anticipate to see the nozzles once a project has been accomplished.
As we can see there are many levels to go from metallic to nozzle head with each nozzle taking a big effort by varied professionals to complete to the permitted normal.
Not only do water mist nozzles require a number of levels of machining and assembling, they have to also undergo a string of tests in order to be accredited for set up. Once put in, there are even further tests undergone, typically by third-party organisations to guarantee that the complete hearth suppression system to finally be handed over to the shopper.
Water mist technology assures safety, quality and assurance through the stringent testing that’s required.
With the recent publication of water mist standards, significantly in Britain over latest years, building builders can now be assured that the quality required for water mist techniques is now at an equal standard to different suppression techniques.
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