8mm tank connector???

[Ian_Edwards]

Hi, I've spent quite a lot of time Googling, looking for a way of connecting an 8mm ridged plastic pipe from my water maker to a Vetus water tank, without success.

I can see two way of doing it, but here might be many more, if you know what you are doing!

I can tee into an existing flexible overflow hose line which is has a 16mm ID, so I'd need a 16mm barbed hose tee, with an 8mm (5/16") compression fitting on the branch.

Or, and this is my prefered method, a 8mm (5/16") tank connector, this would go through the top of the Vetus plastic water tank which is about 8mm thick. The tank fitting needs to be leak proof, so it doesn't leak when the tank is full, so it would need some form of gasket, but it doesn't have to withstand any great pressure.

The fittings can be brass or plastic, or even SS.

The best I can find at the moment is a 1/4"BSP male to 8mm compression fitting connector with a 1/4" BSP back nut, to which I'd add a nitrile rubber gasket. But I'm unsure if the thread on the 1/4" BSP side will be long enough to go through the tank and with enough room for both the back nut and the gasket, which will be about 2mm thick.

Can anyone think of a smart way of doing this?

 

[billcole]

How about a " Seaflow Brass Compression Bulkhead Coupling (8mm Tube OD / 3/8" Bulkhead) Part No. 304526 " from ASAP Supplies, its a straight 8mm compression fitting, but with extra thread length to go through a bulkhead (or into the top of a water tank !)

http://www.asap-supplies.com/marine...through-bulkhead-compression-connector-304526

 

[lw395]

https://www.grippatank.co.uk/8mm-bulkhead-connector

I used a conhex brass one for a fuel tank once.
I found one with a bigger flange to support the gasket/o ring against the tank.
Bulkhead is the key word to google for.

 

[Ian_Edwards]

How about a " Seaflow Brass Compression Bulkhead Coupling (8mm Tube OD / 3/8" Bulkhead) Part No. 304526 " from ASAP Supplies, its a straight 8mm compression fitting, but with extra thread length to go through a bulkhead (or into the top of a water tank !)

http://www.asap-supplies.com/marine...through-bulkhead-compression-connector-304526

Thanks billcole you're a star.

You wouldn't believe how long I've searched the ASAP site for something which would do the job, I was searching for tank connectors, I didn't think of using the term bulkhead.

If I just use the short side of the fitting to attach the 8mm pipe, the backnut will provide the compression required to make a good seal on the tank, and there may be room for a big plastic washer on the top to help ensure that it seals properly,

 

[rogerthebodger]

Thanks billcole you're a star.

You wouldn't believe how long I've searched the ASAP site for something which would do the job, I was searching for tank connectors, I didn't think of using the term bulkhead.

If I just use the short side of the fitting to attach the 8mm pipe, the backnut will provide the compression required to make a good seal on the tank, and there may be room for a big plastic washer on the top to help ensure that it seals properly,

Would one of these do the job

http://www.asap-supplies.com/marine...-skin-fitting-for-antisiphon-devices-doorb08p

 

[Ian_Edwards]

No, the fitting you suggest is for hose, the 8mm pipe I have is ridged and needs either a push on fitting or a compression fitting.

I've ordered a bulkhead fitting from ASAP, as suggested by billcole and it's already waiting for me at the yard, so i can fit it this weekend.

But thanks for the suggestion.

 

[rogerthebodger]

No, the fitting you suggest is for hose, the 8mm pipe I have is ridged and needs either a push on fitting or a compression fitting.

I've ordered a bulkhead fitting from ASAP, as suggested by billcole and it's already waiting for me at the yard, so i can fit it this weekend.

But thanks for the suggestion.

Bulkhead connectors do not seal very well to tanks. they are mainly used to protect /connect a pipe run through a cabin bulkhead / cabinet. The outer thread back nuts do not have a very big surface to seal against the tank.

I normally weld a big washer to a bsp socket using bolts to clamp to tank and screwing the appropriate fitting into the socket.

I will have a look at some pics to see if I show how I have done my water tank water maker inlet.

 

[David2452]

Bulkhead connectors do not seal very well to tanks. they are mainly used to protect /connect a pipe run through a cabin bulkhead / cabinet. The outer thread back nuts do not have a very big surface to seal against the tank.

Had you written do not seal very well on plastic tanks I might agree but I use them on a very regular basis (on metal tanks) in combination with fibre washers and have never, ever had an issue not just on the top but even on tank walls where they are often submerged.

 

[rogerthebodger]

If you use this type of back nut

Would be OK but this type has a much smaller sealing surface thus IMHO more of leakage.

 

[pete]

I like these connectors they are very cheap from any plumbers merchants the rubber washer (that goes inside) can be replaced with a fibre washer depending on fluid no nut inside tank to hold and tightened from outside, large flange inside and outlet can be converted to almost anything using standard plumbing fittings.

15mm tank connector


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Pete