bendyone
Well-known member
Tru design say its fine but a suveyer has said not recommended. Any views?
Tru design Seacocks in the engine space.
- Thread starter bendyone
- Start date
vyv_cox
Well-known member
They are made from glass reinforced nylon. Pretty fair heat resistance but I think that you will have far bigger problems to worry about before they begin to melt.
lustyd
Well-known member
Ask the surveyor to back up what they're saying with some evidence. They ought to be able to show you some regulations or documentation to explain their spurious claims.
pmagowan
Well-known member
What is your hull made of?
lustyd
Well-known member
Or, possibly more importantly, the hose connecting the cock to the engine/strainer.
bendyone
Well-known member
He is saying "not recommended" - not "can not be used"
Cariadco
Active member
If they were melting, Fire brigade on their way and you're probably swimming away from the Fire!!!
lustyd
Well-known member
He can say whatever he likes, but will need to justify such statements with some kind of evidence otherwise TruDesign would have very good grounds for action against him.
geem
Well-known member
Fire tends to not burn low down so easily. Fast growing fires are vertically growing. Meaning they propagate upwards if the fuel is there to burn. In addition, anything connected to the hull is cooled by the seawater on the other side. Flexible pipes are far more likely to fail before glass reinforced through hulls in a fire.
Most boats burn upwards then more slowly downwards before sinking. Often the section of grp from waterline downwards is the only bit left.
If you get to the point where the fire is so large that the seacocks are burning, you will long since have got off the boat. The engine space will be an inferno.
Most boats burn upwards then more slowly downwards before sinking. Often the section of grp from waterline downwards is the only bit left.
If you get to the point where the fire is so large that the seacocks are burning, you will long since have got off the boat. The engine space will be an inferno.
Sandy
Well-known member
Who is making the recommendation, the surveyor or a significant body of evidence? If a significant body of evidence he will be able to able to give you multiple references.
I heard all sort of old wives tails given by surveyors as fact. The most comical one was somebody who had some very strange ideas about osmosis and the movement of liquid through a GRP mass.
rogerthebodger
Well-known member
This is yet another of recommendations made without any true facts.
I had a so called Engineer state that a sealed steel structural section will rust internal due to air being trapped in side.
The issue he did not understand is that rusting consumes the oxygen trapped inside and once the Oxygen is used up no more rusting can take place.
The saying "a little knowledge is a dangerous thing" is very true in all forms of Engineering
I had a so called Engineer state that a sealed steel structural section will rust internal due to air being trapped in side.
The issue he did not understand is that rusting consumes the oxygen trapped inside and once the Oxygen is used up no more rusting can take place.
The saying "a little knowledge is a dangerous thing" is very true in all forms of Engineering
fisherman
Well-known member
The SFIA insisted on all sorts of fire protection: fireproof resin finish in the engine space, gas, fine water spray, metal pipework (even though there has to be a flexi connector) etc, but in the end on the firefighting course we were told "With GRP, even if you've got all this firefighting stuff just get out a mayday and get off as quick as you can"
Portofino
Well-known member
You are all peering down the wrong end of the telescope.
Could it be chemicals often leaked out in the ER ( fuel , old oil etc as examples but not limited ) might degrade the nylon latently ? Or repeated heat cycles over the years results in embrittlement ?
Its more likely that because the person fitting them thinks it’s fit n forget .Parked the whole sea cock problem .
While trad metals have certainly inspection and change out regimes are better at resisting ER leaks and heat cycles and of course folks inadvertently standing on them or dropping eg a battery on them !
Could it be chemicals often leaked out in the ER ( fuel , old oil etc as examples but not limited ) might degrade the nylon latently ? Or repeated heat cycles over the years results in embrittlement ?
Its more likely that because the person fitting them thinks it’s fit n forget .Parked the whole sea cock problem .
While trad metals have certainly inspection and change out regimes are better at resisting ER leaks and heat cycles and of course folks inadvertently standing on them or dropping eg a battery on them !
vyv_cox
Well-known member
No. Nylon has excellent resistance to hydrocarbons, it is used for gasoline in many applications. Glass reinforcement offers superb resistance to thermal fatigue and embrittlement.
There is essentially no real difference between plastic and metal seacock strength or chem resistance (as a metallurgist it pains me to say this!). The only problem is that the wall thickness is increased to match the strength, making them more bulky.
geem
Well-known member
I have the Forespar marelon glass reinforced versions. They are bulky but very strong and stable. I can see on some applications there would not be space to locate them. Also, they only do them with hose tails. No other option. By comparison, the trudesign valves look vulnerable. I am sure they are not but they are quite a lot slimmer
lustyd
Well-known member
The manufacturer doesn’t seem to think so and neither do the certification organisations. There also appears to be no evidence suggesting an issue unless you have more than speculation to offer?
Bobc
Well-known member
Glass-filled nylon. Thermo-set, so will not melt. If these melt, so will your hull. The hoses will go long before.
Clancy Moped
Well-known member
I'm going back a bit, but insurance companies said no, is this still the case?
lustyd
Well-known member
Which ones, specifically what did they say?
Plum
Well-known member
My understanding is that nylon is a thermoplastic....... not a thermoset