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Ice Skating Rink - Movable
Self-Contained & Self-Sufficient
in a standard 40 foot hi-cube ISO container


While on the road, the Rink Floor Accessories

(headers and pipes) can be stowed inside the container



Overview

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Three 3D-pictures above show the Heat Exchanger cum Brine Recirculation Assembly,
the fourth one showc the RPE-Unit. The pictures can be enlarged to A4 or US Letter landscape
print-out sizes by hitting them. Drag the enlarged pictures onto your desktop; they will open
for printing in PictureViewer or Adobe Photoshop or any other graphic software.

The RPE Unit delivers compressed refrigerant gas through the oil separator to the condenser (plate heat exchanger). Condensed refrigerant (liquid) flows by gravity to the rceiver. The oil separator, the condenser and the receiver are shown in red colours. Liquid refrigerant from the receiver expands over a thermostatic valve and associated automatic controls to the brine cooler (plate heat exchanger) and evaporates. Cold refrigerant gas then returns through the liquid separator to the RPE Unit. The brine cooler and the liquid separator are shown in blue and light blue colours respectively. Only the main refrigerant lines - i e suction and discharge lines - and the brine pipes are shown on the pictures; the liquid pipes are not shown. For details of the piping, please consult attached Conceptual Piping Diagram.

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Two 3D-pictures above show Bird's Eye View Cut-Away of the Container,
Front and Rear Views. They can be enlarged to A4 or US Letter landscape print-out sizes
by hitting them. You can drag the enlarged pictures onto your desktop; then they will open
for printing in PictureViewer or Adobe Photoshop or any other graphic software.

Between the oil separator and the brine cooler is the brine reservoir - accessible through an opening in the roof of the container. In the bottom of the tank - just above the connection to the pump (suction outlet) - is a perforated intermediate bottom plate. When new brine is made, common salt - NaCl, or CaCl2 if preferred - is poured into the brine reservoir. New brine must be recirculated until all the salt is dissolved before the refrigeration is turned on. Two pumps, for recirculation of the condenser water and the brine, are mounted on the base frame, together with associated stop valves and strainers. To simplify the holding of spares, the two pumps are selected identical. Hence, one extra pump can be kept as a spare unit for both.




The RPE-Unit

The RPE Unit (Refrigeration-Power-Electricity) consists of (a) the refrigerating compressor, (b) a diesel engine and (c) an electric alternator, all connected shaft-to-shaft as shown on the picture above. A State-of-the-art Brine Cooler facilitates a compact machine room and saves 20% on the consumption of oil fuel compared to installations with conventional generating sets. Some two-thirds to three-quarters (67% to 75%) of the shaft power are transmitted directly from the flywheel end of the diesel engine to the refrigerating compressor, over a manual disengaging clutch and a flexible coupling. Hence, the low oil fuel consumption.

The electric power - required for auxilliary consumers in the plant (pumps, fans), the automatic controls and lighting in the container - is generated by an electric alternator, which is driven off the front end of the diesel engine over a flexible coupling. On top of the alternator is a combined electric switch board and control panel, shown in yellow with light green covers. To ensure proper shaft-to-shaft alignment of the three machines at all times while the container is on the move, the base frame of the RPE Unit is of a sturdy design and set upon a three-point suspension (two at the sides of the compressor and one below the alternator).




The Cooling Tower. The picture can be enlarged to A4 or US Letter landscape
print-out size by hitting it. Drag the enlarged pictures onto your desktop; it will open
for printing in PictureViewer or Adobe Photoshop or any other graphic software.

Excess heat from the refrigeration and the diesel engine is rejected to the atmosphere through a vertical induced draft Cooling Tower, made from fiber glass reinforced plastic (FRP) with corrugated PVC splash deck ('filling'), placed in the rear of the container (Bird's Eye View and Cut-away Views above). The cooling tower discharges hot and humid air to the atmosphere in a vertical-up direction, through the roof of the container. A propeller fan is driven directly off the shaft of a vertical electric motor and the sprinkler head ('cross tree') rotates from the jet effect of the recirculated water.

The equipment can operate with R22 or R404A or any other environment-friendly refrigerant, as preferred. The latter (R404A) will develop about 15% more refrigerating capacity. The package is built up from the following components, or their approved equivalents:

1
GRASSO Model RC69 reciprocating compressor,
with six cylinders in a W-configuration
2
Mercedes Benz Model OM 447 industrial diesel engine,
turbocharged, with six cylinders in-line,
developping 116 kW (157,8 hp) at 1500 rpm
3

Newage-Stamford electric alternator,
self-exciting and self-regulating, 35 kVA (the three machines
are set upon a welded steel frame to form the RPE Unit)

4
ESK oil separator, matching the compressor
5
GUENTNER ThermoWave Model TL-250 refrigerant
condenser (plate heat exchanger)
6
ESK liquid refrigerant receiver, matching the application
7
ESK liquid separator, matching the compressor
8
GUENTNER ThermoWave Model TL-250 brine cooler
(plate heat exchanger)
9
Brine Reservoir, from stainless steel
10
Two Pumps - 7,5 kW each, for recirculation
of the condenser water and the brine
11
Valves and Automatic Controls for the refrigerant,
water and brine piping
12
Electric Switch Board and Control Panel - combined

Items 4 through 12 above will be set upon a welded steel base frame to form the Heat Exchanger cum Brine Recirculation Assembly shown in the three pictures above. Operating with Refrigerant R22, the refrigerating package will have the following Performance and Technical Data:

Refrigerating Capacity
237,8
kW
Outgoing Brine Temperature
-10
°C
Ambient Wet Bulb Temperature
28
°C
Oil Fuel Consumption (approximate)
25
lit/hr
Overall Dimensions of Container, LXWXH
12,2X2,44X2,6
m
Weight, including rink floor accessories
9.000
kg

Hence, the package will refrigerate the ice floor with a Specific Capacity of 237,8/600 = 0,396 kW/sqm, equivalent to 341 kcal/sqm. It is visualised that, in hot surroundings it will take 36 to 48 hours to build up a rink floor of 25 to 30 mm.



The Rink Floor Piping. The picture can be enlarged to A4 or US Letter landscape
print-out size by just hitting it. Drag the enlarged pictures onto your desktop; it will then
open for printing in PictureViewer or Adobe Photoshop or any other graphic software.

The 3D perspective drawing above shows the details of the brine piping in the rink floor. The pipes are to be laid out on a level and dry ground - or on a concrete floor - and covered to the top of the spacers with fine sand (preferably from the sea shore or with comparable consistency). The refrigerating equipment in the container as described above is connected to the rink floor headers through flexible hoses with quick-release couplings. The delivery of accessories for the rink floor includes following:

No Qty
Description
1
80
Pipe Loops; from 25 mm OD polybutylene tubes
with 2,3 mm wall thickness, 60 m long, connected
with quick-release connections to the headers
2
4800
Spacers; from stainless steel, as shown on the drawing
3
8
Headers; from polybutylene tubes, in five 5 m lengths
of 6", 5", 4" and 3" NB each; connected
with quick-release couplings
4
10
Flexible Hoses; 125mm NB and 5 m long, connected
with quick-release couplings

The accessories for the rink floor will be stowed on racks, shelves and hangers, firmly installed in the container to prevent bouncing around during the transport (Bird's Eye View and Cut-away Views above). The equipment would generally be of German origin.

To save on the cost for manufacturing and transport of the container, we offer to supply new or 2ndH (used and reconditioned) 'hard core' equipment components only - namely; compressor, diesel engine, alternator, heat exchangers and pumps - together with drawings for a local fabrication of the less sophisticated items and assembly of the whole plant.

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Last updating: 20 March, 2007 9:09