How to calculate the cooling capacity of a chiller

02.11.2020

METHODS FOR CALCULATING THE COOLING CAPACITY OF THE CHILLER.

HEAT DISCHARGE OF MATERIAL

Cooling capacity Q = P x K

Where:

P = amount of processed products kg / h

K = kcal / kg h (heat capacity of the material)

Plastics:

Material / Specific heat

ABS / 130

ACRYLIC / 75

NYLONS / 180

PET (GENERAL) / 150

POLYCARBONATE / 70

HD PLYTHENE / 200

LD POLYTHENE / 180

POLYSTYRENE / 120

POLYPROPYLENE / 150

PVC / 120

PVC (+ 30% plasticiser) / 130

Metals:

Material / Specific heat

ALUMINUM / 215

ZAMA / 125

BRASS / 108

ACCOUNTING OF THE HOT CHANNEL OF THE TPA MOLD

Cooling capacity Q = Pr x 860 x K

Where:

Pr = hot duct power in kW

860 kcal / hour = 1 kW

K = correction factor (usually 0.3; K = 0.3 for isolated HA K = 0.5 for non-isolated HA)

COOLING OIL FOR CASTING MACHINE (TPA)

Cooling capacity Q = PM x 860 x K

Where:

Pm = oil pump motor power kW

860 kcal / h = 1 kW

K = speed factor (usually 0.5; k = 0.4 for a slow cycle, k = 0.5 for a medium cycle, k = 0.6 for a fast cycle)

For instance:

Injection molding machine with a clamping force of 300 tons and a cycle of 15 seconds (average)

Approximate cooling capacity:

Oil: Qoil = 20,000 x 0.7 = 14,000 kcal / hour = 16.3 kW

Form: Qforms = 12,000 x 0.5 = 6,000 kcal / hour = 7 kW