Ice Blocks

[ChrisYaughn]

Any of you guys fighting Ice blocks in your vacuum lines? WE have had a few and resolved all but one by eliminating leaks. The fitting in this picture gets very cold and has ice forming inside of it.


I also need to get vac guages to put in the blick manifolds so that you can actually see what the vac status is, as opposed to a gauge at the pump.


Any ideas? My next thought is to eliminate the cast fitting in the middle. It seems to be much colder than the copper or the plastic.

[Dan Dauchess]

Eliminate Leaks!

The technical answer: Atmospheric pressure air expanding into the vacuum space (through the leak) cools dramatically. Any moisture in the air cools and in your case - freezes.

Isolate small sections of the vacuum system and identify leaks with a gage. Fix those and move onto the next section.

[scott m]

You have a venturi......Presumably the air is moving from the small hoses to the larger hose. This will cause the air to expand and therefore drop temp......Try making the transition a little more gradual.....

[Joshua Hopkins]

We had that problem one winter not realizing at the time why it was happening we temporarilyput a heater near the machine.

[Carmine Pantano]

we have the same problem but usually only when it's real cold. We put a drain valve at the end of our line to drain any water. Works sometimes, the rest of the time we throw the jet heater on that area for a few minutes and we're good.

[ChrisYaughn]

Wrapped two of these around the problem areas nad we are good so far. Get the ones meant to be used moist

Aslo got some of these. They are only $25 and they can put fittings to slip them into quickl connect valves. Makes it really really nice to be able to glance in and KNOW that I have good vac all the way downstream :D

[Trask Bergerson]

Heat Tape and hot water in our clean off hoses..Spray the manifold block with hot water and we get Vac back instantly.

[scott m]

They make heat tape, sold at RV stores that you can wrap around your hoses.......You can save those heating pads for you eventual bad back..... :D :D

[ChrisYaughn]

As of today I have ran the last 6 parts with no iceblocks. Hard to explain how much that brightens up our outlook. Sounds silly, but .......




I replaced the seals on our pods and picked up 30ft of the heat wire/tape. The only problem with the wire/tape is that they put a friggin thermostat on them. SOoooooooo if the thermostat isn't where the ice is, NO HEAT . No Worries tho'. GOt to looking around and took my DQ cup from lunch, full of crushed ice. Shoved that pesky thermostat in the ice and we were in business


Long live the redneck fabcenter.

[Marmi Natural Stone]

I just experienced the ice block thing this week after 4 years of machining. I had no vacuum at the table and I took the vacuum tube that runs between the two manifolds off and a chunk of ice fell out. Fifteen degree outside temp and no shop heat might have something to do with it. I hobbled along for a couple of days by defrosting the manifolds with a heat gun.

I was told to get Blick manifolds and replace our original Omag ones. Looking at pics of the Blick manifolds, they look like machined blocks of aluminum, similar to what I have now. I'm not quite sure how they would help with the ice problem.

[Jerry Kidd]

The ice blocks are fairly common until people wise up and get a Blick manifold. The biggest issue is the venturi effect. The manifolds you guys are talking about are built in a way that there are a lot of opportunities for creating the venturi effect in several places. Eventually this internal cold generator teams up with the outside temperature and suddenly I get calls from guys telling me that their vacuum lines are frozen at the manifold.

As you see there are plenty of creative ideas for how to battle this problem or you could just get a Blick manifold and eliminate the opportunities for a venturi to exist in your system and also have a much easier manifold to use.

In the metal machining world we use the phenomena with intention to cool parts that should not get oil or water on them. It can be a real asset then or it can strike fear in the heart of a pilot. Unless you have a vacuum system that is driven by the venturi effect of water instead of an oil based pump they are not helpful in the stone world.

Jerry Kidd

[Mark Meriaux]

.....and once the orifice begins to ice up, the venturi effect only gets worse. When high pressure air is forced through a small opening (orifice), the air speeds up, and drops in temperature and pressure. The temperature drop will cause any moisture in the air to freeze up around the opening (choking it off even more), so the air speeds up and the pressure change is even greater, causing colder temperatures and more freezing. I suppose that the Blick manifolds are designed with inlet holes sized large enough to prevent the venturi effect.

[ChrisYaughn]

As a point of reference we have the blick manifolds and do not get ice in the manifold.

My ice comes as a result of needing to replace every quick fitting in the system, and not having the money to do it. I get ice in the "plumbing".

[Marmi Natural Stone]

Thanks guys. I understand what is happening a little better now. I've sent a quote request to Blick for their manifolds.

[Stuart Gill]

My ice comes as a result of needing to replace every quick fitting in the system, and not having the money to do it. I get ice in the "plumbing".

This can often be due to tubing as well. Many times a quick nip of an inch or so to get to a cleaner section of tubing will do wonders.

You can get a bit more life out of petered out quick disconnects by using shrink tubing with adhesive in it that will seal up the leaks. Move all of the good fittings to the manifold and the suspected leaking ones to the pods where you do not remove the tubing as much. Put a 3" section of shrink tube over the pod end fitting with the tubing in and hit it with a heat gun. Not good for changing your tubing out but if the fitting is tanked anyway it will limp along for a bit longer.

http://cableorganizer.com/high-flow-adh ... nk-tubing/

Not the perfect solution but a 48" tube of shrink costs a heck of a lot less than a set of fittings.

STU

[Mark Meriaux]

To back up Stuart's post........small pinhole leaks can also cause the venturi effect. Consider the air around a machine bed. It's wet, and at much higher pressure than inside the vacuum hoses. When that wet air gets suck into the much lower pressure vacuum, the moisture will freeze and cause the ice blocks.

Eliminate any leaks.