Condensate pumps Mechanical pumps and pumps traps
9
Sizing and selection How to size and select From the inlet pressure, backpressure and filling head conditions given below, select the pump size and check valve package which meets the capacity requirement of the application. Specify pump body - Type PTF4. Select optional extras as required. For kg/h, multiply the capacities below by 0.454 (For gpm, multiply the capacities below by 0.002). Backpressure in bar g = lift height (H) in metres divided by 10 plus the pressure in the return line (Backpressure in psi g = lift height (H) in feet x 0.433 plus the pressure in the return line). Added to this is the downstream piping friction pressure drop in bar g (psi g) calculated and based on the maximum instantaneous discharge rate of the respective pump selected - See TI sheets. Note: To achieve rated capacity, the pump must be installed with check valves supplied by Spirax Sarco. Use of a substitute check valve may affect the performance of the pump. Capacity lb/h when installed with the recommended filling head above the top of the pump.
Condensate load
9 545 kg/h (21 000 lb/h)
Steam pressure available for operating pump
5.5 bar g
(80 psi g)
Vertical lift from pump to the return piping 9.1 m
(30 feet)
Pressure in the return piping (piping friction negligible)
1.7 bar g (25 psi g) Filling head on the pump available 610 mm (24")
Solution: 1. Calculate ' H ', the total lift or backpressure, against which the condensate must be pumped: ' H ' Metric = (9.1 m / 10) + 1.7 bar g = 2.6 bar g ' H ' Imperial = (30 feet x 0.433) + 25 psi g = 38 psi g) 2. From the capacity table, given an inlet pressure of 5.5 bar g (80 psi g) and a backpressure of 2.8 bar g (40 psi g), choose a PTF4 pump with stainless steel check valves, which has a capacity of 12 264 kg/h (26 980 lb/h). Note from capacity multiplying factor charts: A. If filling head were 457 mm (18") PTF4 pump capacity would be: = 0.98 x 12 264 kg/h (26 980 lb/h) = 12 018 kg/h (26 441 lb/h) B. Pump capacity using compressed air would be (% backpressure is 5.5 to 2.6 bar g (38 to 80 psi g) = 47% e.g. use 50%): = 1.85 x 12 264 kg/h (26 980 lb/h) = 22 688 kg/h (49 914 lb/h).
Intended use This product fully complies with the requirements of the European Pressure Equipment Directive 2014/68/EU and is certified for use to Category III within Group 2 Gases and to SEP for Group 2 liquids.
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The product carries the mark when so required. This product is designed and built to the pressure vessel code ASME section VIII Division 1.
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TI-P135-13 CMGT Issue 5
PTF4 Pivotrol ® Pump (patented)
version Dual Mechanism - Pressure Powered Pump
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