Atlas Slice Ice Machine

[Glide]

Hi Guys,
I am new here and would like a help. . . .
I need a Manual of the Altas Ice Machine & Mitsubishi Compressor. Hope somebody out there have one.

Four months ago, We bought and assembled an Ice Machine from Japanese trader with following components
(1) Atlas Slice Ice Machine Type V70B, SN2034, built in Denmark, 1979. In its name plate, R: Brine.
(2) Mitsubishi Semi Hermetic Compressor model MZ-4S R22 19KW motor (with unloader)
(3) Direct expansion, Air cooled condenser system.

My problem is, I could not get the projected capacity of around 4 Tons (as advised by the Japanese Trader).
The unit was installed in a ship and work to produce the said capacity using R22. The original brochures/manuals were not available. It was disassembled and shelved for sometime, until we came across of it.

The system is running already but erratic operation. Ice production was not constant, some part of the rotating drum dont produce ice. We constantly monitor compressor body for heavy frost and unload it to prevent liquid slugging. We already did checked the superheat. To maximize ice formation in the drum, we try to open the expansion valve but have to watch out for the copmpressor. Gage pressures 250 and 10,psig. If we can maintain the suction pressure at 10 or above, ice production is accetable but it gets down to 5 until the cut-off trip at 2psig. We are considering a suction pressure modulating valve before the compressor but still open to other options.

It seems that the evaporator had inefficient heat transfer or its the application?

As of now, we try to focus on how to normallized its operation even if cant get the target ice production. If we can verify the evaporator's capacity and application,we may improve the situation.

We had installed and assembled refrigeration units for storage and blast freezer before but this one really force our back against the wall.

I got a tip from somebody and suggest to try this site for assistance for that forsaken manual/brochures. I hope somebody did encounter and able to acquire the materials and found it worth while to preserve it for some antic collector.

Yours truly,

Glide

[Andy]

Glide Welcome:)

can you give us the suction pressure in degrees c and the suction temperature at the compressor. (superheat)

Sounds like not enough refrigerant entering the evaporator, but proper superheat readings will tell us.

Kind Regards Andy:)

[Glide]

Dear Andy,

I appreciate your interest on my inquiry.

We installed a Danfoss txv,TE5 w/ external equalizer, orifice #02. After start-up suction press. ranges from 10(-28deg.C) to 5psig(-34deg.C) @ comp.Suction pipe's temp (approx. 1ft from comp) ranges from -10 to -15deg C.
There really lot of frost around the body. During the commissioning period, lots of adjustment from drum speed, water flows, clearance of scraper, txv and control sequence. Lately, we concentrate on the system capacity.

We try to maintain the s.h. at the minimum, 20degC, but the evaporator's freezing surface had incomplete ice built-up. There s also a fairly sized suction accumalator before the suction filter & comp. w/ internal heat exchanger for the liq.line. I dont know the limit of sub-cooling the liquid refrigerant - @ existing system, cu.piping of liq line produce condensate after the exchanger. We decide it was too low and re-route the line from the exchanger.

We did encouter lots of system problem, low oil press due to mis aligned oil pump; low comp. discharge due to oversized condensing coil;big pressure difference bet. comp.suction and evaporator's pressure readings due to clogged suction filter, same w/ liq.line filter, water pump; and belts.

One by one, these were fixed and corrected. Lately, the sight glass just turn to yellow and txv, body/head was well frozen.
After running it w/ new sets(3pcs filter core) of filters for 120hrs.(accumulative running time), theres a slight streak of green color at the glass.We will replace it w/ new set @ 150th and cont. it until we got result.

Clearly, we had to fix this problem before the issue of ice capacity.

When we finally fix it, we have 2 schemes in the dwg. board:
1) we will utilize the unloader during optn. If comp suction press go down to 5psi, unloader activate and cut out when it reach 15psi.
2) we will utilize the heat exchanger @ S.A. by introducing discharge gas from comp and routing it to liq. receiver using 3/16 cu tube. Planning to add solenoid valve so that it not activate during start-up and only during low press.

3) Let someone(optr in the ship from where it came from) to look at the evaporator if it is performing to its capacity.

Do you think it will work?

Thanks a lot.


Hopefully yours,

Glide

[Peter_1]

From what I’ve read, I see that you know what you’re doing., so I don’t think we have to give you basic information

This seems the same working principle as a Ziegra or a Maya.
They need to evaporate around -17°C.

The Maya machines were prone to leak after some time through small pinhole leaks around the aluminium cylinder but this has nothing to do with lack of capacity.
Make sure that the LP cut-out is set above atmospheric pressure so that moisture can’t enter into the system.

Opening more the TXV will not solve the problem because you already spoke about liquid slugging.

When the drum doesn’t freeze completely, then there’s something wrong with the normally installed baffles inside the rotating drum. They’re there to ‘spread’ the refrigerant uniform on the inside of the drum.

What’s the length and diameter of the rotating cylinder? Are compressor and ice generator fit for each other? Is the drum not to small for the given capacity.
Just an estimate, the drum needs to be at least 60 cm to 80 cm long and have a diameter of +/-
cm…something like that.

Do you have the possibility to make a picture of the gene

[Peter_1]

Perhaps this can be usefull http://www.scotsman-ice.com/docs/uploaded/sct/manual/marman.pdf

See that the MAR evaporates at -24°C , so much lower then I suggested.

[winfred.dela]

Hi Glide,


The evaporator maybe made for brine cooling and not for direct expansion system. Just don't know what percentage will it increase or decrease your capacity.

Maybe this will give you an idea, a thread about discussion on coefficient of heat transfer:
http://www.refrigeration-engineer.com/forums/showpost.php?p=39972&postcount=90

Re evaporator capacity, you will need a brochure/manual to ascertain if the size of the evaporator is correct.

If there will be no brochure/manual, hope some of the masters and old timers can give a ballpark figure of the cooling capacity based on the evaporator diameter and length.

[pemo]

Hi Glide.

Did you manage to make it work? I work at Buus Refrigeration and we took over the production of Atlas / Sabroe's iceflakers last year. I may be able to help you out.

Best regards, Peter.


[quote=Glide;49525]Hi Guys,
I am new here and would like a help. . . .
I need a Manual of the Altas Ice Machine & Mitsubishi Compressor. Hope somebody out there have one.