You see what happened when you burst the flexible hose.
According to research conducted by general insurer IAG, flexible braided hoses accounted for 22% of water damage claims in Australian households in 2016 with the claims most likely to be for kitchen and bathroom damage.IAG advises home owners that flexible hoses have a lifespan of between five and ten years and should be checked by a licensed plumbing professional every two years.
The onus is on the plumbing industry to work together to do something about this issue, as it is unlikely consumers will heed this warning.
Plumbing Connection held a workshop in July to discuss what types of products are failing and how to reduce the incidence of failures.
The aim of the workshop was to start a discussion about how the plumbing industry can take the issue forward.
Plumbing Connection hosted a workshop in July to discuss bursting flexible braided hoses.
The first braided stainless steel flexible hoses came onto the Australian market 25 years ago and quickly became popular with the plumbing industry.These hoses were made from rubber or PEX and armoured in braided layers of steel and were used to replace standard copper pipe installations in kitchens, baths, hot water services and laundries.The article focuses on the performance of the tube version.
The time it takes to hook up hot and cold water pipe appliances is greatly reduced by the use of flexible hoses.They overcome alignment problems and reduce labour costs and noise in pipe work, as well as eliminate brazing, welding, cutting, re-shaping and waste.
The popularity of these connections has led to them being included in the supply of many tapware ranges.There are seven million flexible connections sold in Australia each year and some of them are low-cost products from hardware stores.
Flexible braided hoses are the number one cause of internal flooding in Australian homes according to recent data released by insurance companies.
There have been reports of some claims costing tens or hundreds of thousands of dollars, but the average claim for escape of water in 2016/2017 was $4,818.
According to Cheryl Chantry, properties between 11 and 30 years old are most likely to suffer an escape of water claim.Attendees at the workshop said some flexible hoses burst within a couple of months of installation.
It isn't easy to figure out why this is happening and how it can be prevented.
It is important for the plumbing industry to start a discussion about the risk of flexible hose burst failure.
The braided steel component of the product seems to be failing based on analysis.
The braided layers of steel are designed to prevent the tube from expanding when it is pressurized.The rubber inner core will expand if the steel fails.
A slow leak at the connection point, which runs down the hose into the braided steel, causes this.The deposit is pitting when the levels of chloride increase.The pitting reduces the cross-section of the wires to a point where overload failure occurs.
Australian drinking water has low levels of chloride due to the dissolution of salt deposits.
The general manager of Abey Australia says that the 60/60 rule will allow stress cracking.The water temperature is 60 and the yield stress is 60%.
The deposit of chloride is left behind when the water reaches 60.When the process continues for a long time, the chloride level in the deposit increases until it reaches a level that allows for local STAINLESS STEEL PAIN.They are difficult to detect since the cracks are so fine.
The metal strands of the steel sleeve fail and break as a result of this corrosion.The steel sleeve is no longer able to support the inner lining when enough strands fail.This causes the lining to break and the water to escape.
Most failures are seen under kitchen, laundry and bathroom sinks, toilets and dishwashers, rather than on gas stove cook-tops because of the presence of water exterior to the hose.
According to the engineering director of Materials Solutions Australia, pulling apart a burst flexible connectors clearly shows the path of the water and the evidence of rust.
When put through certain conditions,Stainless steel can become vulnerable.The leak at the connection is the issue and the braiding is appropriate for its function.You can always find a leak path in these hoses, and all the ones I have seen have had one.
There are many reasons why this happens, but four main issues arise from experience in the field.Installation, effects of water hammer, quality of materials in the manufacturing process, and household cleaning products being stored within the vicinity of flexible braided hoses are some of the things that are listed.
The issue of bursting flexible hoses is largely preventable and the majority of these reasons are not due to poor quality.
The rubber inner tube burst when the steel braided sleeve corrodes.The image was supplied by Neil and Craig Baker.
Installation issues are playing a big role in bursting flexible braided hoses, particularly in regards to the tightening of the nuts at either end.
The design of the second nut, which connects to the tap assembly, makes it possible for the first nut to become loose.
The second nut can loosen if the first nut is not gripped or held at the end.
The slight loosenment leads to a leak that allows water to migrate across the rubber seal face down to the back face of the nut and eventually onto the braiding.
One or both of the nuts need to be tightened by the installing plumbing professional.The seal will break if it is too tight or loose.
The result is the same as before, which is wire breakage and the rubber tube bursting.
The rise of the do-it-yourself culture in Australia is increasing the likelihood of flexible hose failures, as they encourage handymen to attempt installations themselves.
Budget Direct says on its website that this is compromising the integrity of flexi hoses in homes as it is more likely to result in flexible hoses being damaged at the time of installation, which then increases the chance of bursting.
It is feared that insurance companies will begin to deny claims if customers can't prove installation and regular maintenance.
David Pockett says there is a significant risk for the home owner and it is likely to get worse given the high rate of losses insurers are currently reporting.
It is a contributing factor that can play a role in the failure of a flexible braided hose if it is brought to a vulnerable point.
Phil Woolhouse has more than 30 years experience in the plumbing sector and is the principal consultant at his company.The rubber seal is under constant force because of the speed at which modern tapware can be isolated.
The higher the pressure shock, the quicker the mixing taps can be closed.Modern fast-closing tapware can cause massive shock pressures within the piping system.
This can cause the rubber seal to form a permanent stress if it is compressed over time.
Some rubber will shrink and have a memory effect.The nut loosens and there is less contact pressure on the seal face, allowing water to leak.
Fume cupboard environments can be created if flexible braided hoses are installed under kitchen or bathroom sinks.
With the price of flexible braided hoses continuing to drop and a number of new products entering the market, there are concerns that the quality of steel and brass components being used in some hoses are contributing to the early failures being seen in the field.
There are flexible braided hoses where the brass barb fittings are not heat treated.
It had not been carefully controlled during the manufacturing and thermal cycling process that alpha-beta brass had been used.When the islands form a continuous network, water can pass through the cross-section of the barb fitting from the inside to the outside.The water is in contact with the rubber tube of the hose in the crimped area.
Tom Davies, general manager of Aquaknect Flexibles, has concerns about the wire size being used on the braiding as a weaker braid is more likely to fail.The minimum wire size used by the company is 0.23mm.
There are some manufacturers where the largest wire is less than 0.15mm, which is 33% thinner, and you can see through the gaps to the rubber underneath.Tom says that with the tap being turned on a few thousand times, the hose flexes back and forth, causing a weaker braid to fail regardless of whether the braid has broken.
There are suggestions that these low-quality products are able to make it to market by unscrupulous suppliers that are defrauding the WaterMark product certification system with what is known as the golden sample.
The golden sample is when a product supplied for third-party testing is of a high enough quality to pass requirements but it is replaced with a low-cost alternative when large orders are placed.
If flexible braided hoses are installed in areas where household cleaners are kept under sinks and cupboards there is a chance of them bursting.
The level of chlorine in the air is affected by the presence of stored household cleaners in closed environments.After the product has been used, these remain in the air.
Tom says that most cleaning products are stored in bathroom, kitchen or laundry sink cabinets because of the high humidity caused by condensation from hot water being run through the taps and bowls above the cabinet.
hydrochloric acid is highly corrosive when dissolved in humidity.The number of failures in this environment is high.
According to Cheryl from IAG, research shows that flexible braided hoses erode faster if household cleaners are stored under the sink.
A discussion about the issue of bursting flexible braided hoses is an important first step but action needs to be taken to bring the problem to the attention of regulators, government, TAFE's, manufacturers and consumers.
It's still only a small percentage of the industry that knows about it.
At the workshop hosted by Plumbing Connection, there was consensus that the current water supply needs to be updated.
The Standard needs to reflect technology and practicality.There have been many regulatory and technological changes since the current version was last reviewed in 2006
There are concerns that manufacturers are actually writing their own interpretation of the Standard, with one supplier on the shelves of a prominent Australian outlet providing aselective product warranty that covers domestic use only and not for commercial applications.
Proposed changes to the Standard include a minimum wire diameter for the introduction of the stainless steel braid, future testing for things like corrosion, and markings on the inner liner of hoses to identify the manufacturer.
A change to the Standard will not have much of an impact because there are things within it that are not ideal.
There are specific requirements for how flexible hoses are installed and maintained.I think that will solve more problems than the Standard.