Introducing water mist expertise – Part 2

Water mist expertise remains to be a relatively new idea when it comes to hearth suppression, yet it’s proving to be an exciting growth in the business. As the trade evolves, so do the laws, legal guidelines and requirements so as to improve safety and allow improvement. These can vary largely from nation to country, and even area to region.
The means by which a water mist system operates is an identical mechanism to the normal sprinkler system in that the nozzles are often activated by way of a bulb which blows at a particular temperature allowing for the activation of the mist via 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 large ‘bar’ of metallic, to becoming the environment friendly water mist nozzles we see put in in plenty of new projects/developments across a lot of the globe today.
The metallic arrives for cutting
Here at Dual Mist Ltd, Stainless Steel 304 is used for so much of components as this can be very durable and corrosion resistant in comparison to other related metals. The body is machined out of Brass CZ121, which arrives as giant bars of metal that are delivered to the warehouse in 3m lengths. This is then minimize into two smaller components ready to insert into the machine. Not all water mist companies have the ability to machine the components they require in-house though it might possibly show very beneficial for cost and production purposes as we are about to see.
The steel is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine software is supplied with carbide tooling and high-pressure through coolant systems, with the twin-spindle and twin-turret making haste of the otherwise sophisticated parts. A Citizen M532 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, completely automated – this means it might possibly turnover an unbelievable 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 despatched for Electroless Nickel Plating. This provides a corrosion-proof coating to the brass, enabling it to turn into much more sturdy. All parts 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 components of varied 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 components or ‘components’. These parts are then meticulously put together and assembled by the production team requiring a good quantity of labour earlier than the ultimate product is achieved. Various stages include tightening with specifically adapted tools, urgent using a hand-press and utilizing a specific ‘Locktite’ formula at some phases which is a threadlock that forestalls fixings from coming unfastened in the course of the operational lifetime of the product. The ultimate stage of assembly is carefully loading the bulb and applying the proper load to it using a torque wrench.
The assembled nozzles are then placed on one other machine to have the ability to be labelled and uniquely identified using a serial number. At Dual Mist Ltd that is carried out on a Technifor Laser Engraver fitted with a 4th axis unit earlier than they are able to be positioned through the assorted stages of testing.
Cull Testing
Also known as bubble testing in layman’s terms, this test is to make sure no harm has occurred to the bulb throughout assembly and is a crucial test for LPCB approval. The take a look at involves using a high-powered microscope to measure the size of the bubble in each bulb before putting in warm water to be able to shrink the size of the bubble to nothing. Once this is checked, the nozzles are then left to rest and return to room temperature earlier than the bubble is measured once once more so as to guarantee it has returned to the original dimension within a small tolerance.
Leak Testing
Every nozzle can be stringently tested for leaks by making use of 24-bar stress for 1 hour and guaranteeing no water has escaped. pressure gauge น้ำ is uncommon for any leaks on the production line, but that is an extremely important stage of the testing as leaks might happen if dust is trapped inside the seal face.
Activation Testing
On a month-to-month foundation, random nozzles are also tested for activation by inserting the nozzle on a strain jig at varied pressures and applying warmth to the bulbs. The nozzles ought to all activate cleanly throughout the complete stress range specified to that nozzle.
A member of the manufacturing staff uses a microscope and software to discover out the dimensions of each bubble within the bulb.
At Dual Mist Ltd, these tests usually are not just to assure the standard of the production line however are also an important a part of the LPCB Approval. These approvals enable prospects to recognise that the products they’re shopping for are made to the best possible quality normal in the area.
The disadvantage to this is that the Approval Testing system could 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 via their paces at BRE Global in terms of both hearth testing and component/type approval.
Tamper proofing
In order to make sure that nobody 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 fixed.
The nozzles are then ready to be packaged and sent off for installation.
Here is an instance of a management 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 steel pipes often used in high-pressure systems, low-pressure water methods can use CPVC piping. This is a special kind of fire-resistant plastic enabling quick installation. Instead of threading every pipe, a heated glue can be utilized to shortly construct massive pipe networks. These networks are approved to handle up to 12 bar pressure. The nozzles are screwed right into a particular pipe adaptor utilizing a half-inch fuel fitting.
An electric control panel is fitted for the system management together with pumps and a water tank, normally with a mains feed.
The system is examined, signed off and handed over to the consumer.
The last product once installed. This exhibits how we expect to see the nozzles as quickly as a project has been accomplished.
As we are able to see there are tons of phases to go from metallic to nozzle head with each nozzle taking a significant effort by various professionals to complete to the permitted normal.
Not solely do water mist nozzles require a number of levels of machining and assembling, they want to also endure a string of exams to have the ability to be approved for installation. Once put in, there are even additional checks undergone, typically by third-party organisations in order for the complete hearth suppression system to finally be handed over to the consumer.
Water mist expertise assures safety, high quality and assurance via the stringent testing that’s required.
With the current publication of water mist requirements, particularly in Britain over current years, constructing developers can now be assured that the quality required for water mist systems is now at an equivalent normal to other suppression methods.
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