Introducing water mist know-how – Part 2

Water mist know-how remains to be a comparatively new idea by means of hearth suppression, yet it’s proving to be an exciting improvement within the industry. As the industry evolves, so do the laws, legal guidelines and necessities in order to enhance security and allow development. These can vary largely from nation to nation, and even area to region.
The means during which a water mist system operates is an identical mechanism to the normal 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 by way of a low-pressure water piping system.
Here we have a look at how some water mist nozzles are produced and put in – from arriving as a big ‘bar’ of steel, to becoming the efficient water mist nozzles we see installed in plenty of new projects/developments throughout a lot of the globe at present.
The metal arrives for cutting
Here at Dual Mist Ltd, Stainless Steel 304 is used for a lot of components as it is extremely sturdy and corrosion resistant in comparison to different related metals. The body is machined out of Brass CZ121, which arrives as giant bars of metallic which might be delivered to the warehouse in 3m lengths. This is then reduce into two smaller elements able to insert into the machine. Not all water mist companies have the flexibility to machine the components they require in-house though it could show very helpful for price and production purposes as we’re about to see.
The metal is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine device is supplied 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 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 51 seconds, utterly automated – this means it could turnover an unimaginable 4,000 filters in a weekend utterly unmanned.
The brass heads are additionally de-burred on the machine, removing all sharp edges before being polished and despatched for Electroless Nickel Plating. This offers a corrosion-proof coating to the brass, enabling it to turn into rather more sturdy. All parts are then inspected for dimensional accuracy earlier than the meeting stage.
This Technifor Laser machine engraves each nozzle in preparation for the testing phases.
There are many small components of various sizes and shapes 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 elements are then meticulously put collectively and assembled by the production team requiring a fair quantity of labour earlier than the final product is achieved. Various phases embrace tightening with specially adapted instruments, urgent using a hand-press and using a selected ‘Locktite’ formula at some levels which is a threadlock that forestalls fixings from coming loose during the operational lifetime of the product. The ultimate stage of meeting is rigorously loading the bulb and making use of the proper load to it using a torque wrench.
The assembled nozzles are then positioned on one other machine to find a way to be labelled and uniquely identified using a serial quantity. At Dual Mist Ltd this is done on a Technifor Laser Engraver fitted with a 4th axis unit earlier than they’re able to be positioned through the various phases of testing.
Cull Testing
Also often recognized as bubble testing in layman’s terms, this take a look at is to make sure no injury has occurred to the bulb throughout meeting and is a critical take a look at for LPCB approval. The test involves using a high-powered microscope to measure the size of the bubble in each bulb earlier than 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 rest and return to room temperature before the bubble is measured as soon as 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 stress for 1 hour and making certain no water has escaped. It is rare for any leaks on the production line, however this is an extremely important stage of the testing as leaks may occur if filth is trapped throughout the seal face.
Activation Testing
On a monthly foundation, random nozzles are also tested for activation by putting the nozzle on a pressure 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 production team makes use of a microscope and software program to discover out the size of every bubble in the bulb.
At Dual Mist Ltd, these exams usually are not simply to guarantee the standard of the production line however are also an necessary a half of the LPCB Approval. These approvals enable prospects to recognise that the products they’re buying are made to the best potential high quality commonplace within the area.
The disadvantage to that is that the Approval Testing system may be each expensive and time-consuming – generally needing to be booked a number of months upfront and requiring years of exhausting work to attain.
The nozzles produced by Dual Mist have been put via their paces at BRE Global when it comes to both fireplace testing and component/type approval.
Tamper proofing
In order to make sure 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 stress load setting on the bulb is then subsequently mounted.
The nozzles are then able to be packaged and despatched off for installation.
Here is an example of a control 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 metal pipes usually utilized in high-pressure systems, low-pressure water methods can use CPVC piping. เกจ์วัดแรงดันน้ำ is a particular sort of fire-resistant plastic enabling quick installation. Instead of threading each pipe, a heated glue can be used to rapidly build giant pipe networks. These networks are approved to deal with as much as 12 bar pressure. The nozzles are screwed right into a particular pipe adaptor utilizing a half-inch gas fitting.
An electrical control panel is fitted for the system control together with pumps and a water tank, often with a mains feed.
The system is tested, signed off and handed over to the consumer.
The last product once put in. This shows how we expect to see the nozzles once a challenge has been completed.
As we will see there are many phases to go from metal to nozzle head with every nozzle taking a major effort by various professionals to complete to the accredited standard.
Not solely do water mist nozzles require multiple stages of machining and assembling, they have to also undergo a string of checks so as to be accredited for installation. Once put in, there are even additional tests undergone, sometimes by third-party organisations to guarantee that the whole hearth suppression system to finally be handed over to the shopper.
Water mist know-how assures safety, high quality and assurance via the stringent testing that’s required.
With the latest publication of water mist requirements, particularly in Britain over latest years, constructing builders can now be assured that the standard required for water mist methods is now at an equivalent commonplace to other suppression systems.
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