Load Sizing

A GUIDE TO LOAD SIZING

FOR CHILLED WATER

INJECTION MOLDING = 1 LBS/TON

EXTRUSION = 1 LBS/TON

30 lbs/hour HDPE
35 lbs/hour LDPE
35 lbs/hour Acrylic
35 lbs/hour PP
40 lbs/hour Nylon
40 lbs/hour Derlin
40 lbs/hour Urethane
45 lbs/hour PET
50 lbs/hour PS
50 lbs/hour ABS
50 lbs/hour PC
50 lbs/hour Acetal
70 lbs/hour PVC

SHEET CALENDERING

35 lbs/hour PE
60 lbs/hour ABS
60 lbs/hour PS

PROFILE

50 - 60 lbs/hour HDPE
50 - 60 lbs/hour LDPE
50 - 60 lbs/hour PP
50 - 60 lbs/hour PET
60 - 75 lbs/hour ABS
60 - 75 lbs/hour PVC

FEED THROAT:

1/2 ton up to 400 ton injection.
1 ton over 400 ton injection.

Barrel = 1 ton/" screw dia
Screw = 2 tons
Throat = 1/2 ton up to 3"
Throat = 1 ton 4" to 6"
Gear drive = 100 hp/ton
(oil cooling)

BLOW HOLDING = 1 TON

VACUUM FORMING = 1 TON

40 lbs/hour HDPE
40 lbs/hour PET
40 lbs/hour PVC

70 lbs/hour HDPE & LDPE
70 lbs/hour PP
200 lbs/hour PS
250 lbs/hour PVC

HOT RUNNER MOLDS convert heater watts to btu's and divide by 2. (watts x 3.414 divide by 24,000 Btu's)

Chilled water flow rate is 2.4 gpm/ton.

Chiller ton is 12,000 Btu's

Chiller operating temperature range with water is from 45 F. to 60 F. leaving water temperature.

Chiller operating temperature range with glycol/water is from 25 F. to 45 F. leaving water temperature.

MIXER: lbs/hour x .5 x temp. difference + 0.2 hp. = tons

                          12,000

Approx. temp. in 220 F. and temp. out 100 F.

WATER PUMPS: 0.2 ton/hp.

VACUUM FORMING: S.H. is specific heat of plastic.

Tons = (temp. sheet on - temp. sheet off) x S.H> x lbs/hour

                           12,000 Btu's/ton

* Sheet is cooled by the surrounding air, lbs/hour may be increased by 15%

COOLING & HEATING LOAD: S.H. is specific heat of material.

BTU's = lbs/hour x (temp. start - temp.end) x S.H.

MOLD HEAT UP TIME: S.H. is specific heat of mold material.

Time = weight (lbs) x (temp. start - temp. end) x S.H.

                           heater capacity (Btu's)

FOR TOWER WATER

SPOT WELDERS: 1/4 ton/tip (chilled water)

MOLD ROOM COOLING: 80 sq. ft./ton (16' ceiling)

TRANSFORMER COOLING: 1 KVA = 1 ton

FAN BEARINGS: 0.2 ton/fan motor (2 gpm/fan motor)

Hydraulic cooling:

10 hp = 1 ton

Vacuum pumps:

10 hp = 1 ton

Chiller condenser: 1 ton chiller = 1 ton cooling tower.

Air compressors:

10 hp = 1 ton (internal oil cooling).

10 hp = 1 ton (after cooler cooling).

Tower water flow rate is 3 gpm/ton.
Tower ton is 15,000 Btu'sTower leaving water temperature depends on local wet bulb temperatures, normal range is from 75 F. to 85 F. in the summer months and as low as 50 F. in winter months.

PLATING BATHS: DC amps x DC volts x 3.414 x 75% eff. = Tons

                                            12,000 btu/s

DIE CASTING: Zinc - lbs/hour x 35 btu/lb = Tons   (pour at 800 F. Remove at 600 F.)

                                    12,000 b

              Aluminum - lbs/hour x 325 btu/lb = Tons  (pour at 1200 F. Remove at 600 F.)

                                    12,000 Btu's

STEEL QUENCHING:

Continuous - lbs/hour x 0.166 x (temp. in - temp. out) = Tons

                                        12,000

Batch - lbs/load x 0.166 x (temp. in - temp. out) = Tons

                  quench time (hours) x 12,000

FAN BEARINGS: 0.2 ton/fan motor (2 gpm/fan motor)

TRANSFORMER COOLING: 1 KVA = 1 ton