alleryStart learning →Refrigeration plant capacity for pre-cooling of mass concrete is expressed in tons of refrigeration. One ton of refrigeration is equivalent to:
A12000 Btu/hr
B1200 Btu/hr
C120000 Btu/hr
D3600 kJ/hr
Answer & Solution
Correct answer: A. 12000 Btu/hr
1. The unit's sizing formula Eq. 7.1 divides heat to be removed (Btu/hr) by 12000 Btu/hr.
2. That divisor converts the heat-removal duty into refrigeration tons.
3. So one ton of refrigeration is taken as 12000 Btu/hr in the formula.
4. The maximum concrete placing rate (cyd/hr) multiplied by heat-to-be-removed (Btu/cyd) gives total Btu/hr.
5. The other Btu/hr values misstate the standard one-ton equivalent.
_Source: IGNOU Concrete Technology, Unit 7 "Concreting Equipment" (Mixers, Cableways, Batchers, Buckets, Pre/Post Cooling)._
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