AIM Manual

Motor Application » Pumptec Products (Page 7)

Head Loss From Flow Past Motor

Table 7 lists the approximate head loss due to flow between an average length motor and smooth casing or flow inducer sleeve.

Table 7 Head Loss in Feet (Meters) at Various Flow Rates
Motor Diameter4"4"4"6"6"6"8"8"
Casing ID in Inches (mm)4 (102)5 (127)6 (152)6 (152)7 (178)8 (203)8.1 (206)10 (254)
Flow Rate
in gpm (l/m)
25 (95)0.3 (.09)
50 (189)1.2 (.37)
100 (378)4.7 (1.4)0.3 (.09)1.7 (.52)
150 (568)10.2 (3.1)0.6 (.18)0.2 (.06)3.7 (1.1)
200 (757)1.1 (.34)0.4 (.12)6.3 (1.9)0.5 (.15)6.8 (2.1)
250 (946)1.8 (.55)0.7 (.21)9.6 (2.9)0.8 (.24)10.4 (3.2)
300 (1136)2.5 (.75)1.0 (.30)13.6 (4.1)1.2 (.37)0.2 (.06)14.6 (4.5)
400 (1514)23.7 (7.2)2.0 (.61)0.4 (.12)24.6 (7.5)
500 (1893)3.1 (.94)0.7 (.21)37.3 (11.4)0.6 (0.2)
600 (2271)4.4 (1.3)1.0 (.30)52.2 (15.9)0.8 (0.3)
800 (3028)1.5 (0.5)
1000 (3785)2.4 (0.7)

Hot Water Applications

Hot Water Applications (Standard Motors)

Franklin Electric offers a line of Hi-Temp motors which are designed to operate in water with various temperatures up to 194 °F (90 °C) without increased flow. When a standard pump-motor operates in water hotter than 86 °F (30 °C), a flow rate of at least 3 ft/s is required. When selecting the motor to drive a pump in over 86 °F (30 °C) water, the motor horsepower must be de-rated per the following procedure.

1. Using table 7A, determine pump gpm required for different well or sleeve diameters. If necessary, add a flow sleeve to obtain at least 3 ft/s flow rate.

Table 7A Minimum gpm (l/m) Required for 3 ft/s (.91 m/sec) Flow Rate
Casing or
Sleeve ID
4" High
Thrust Motor
6" Motor8" Motor
Inches(mm) gpm(l/m) gpm(l/m)gpm(l/m)
4-10215-57
5-12780-303
6-152160-60652-197
7-178150-568
8-203260-98460-227
10-254520-1970330-1250
12-305650-2460
14-3561020-3860
16-4061460-5530