Finish Thompson DB 11/15 Series - Manual (Page 5)

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OUT CAUSING DAMAGE TO THE PUMP. However, the pump can operate without liquid in the casing if the pump has a carbon bushing. The exact length
of time the pump can operate dry with a carbon bushing varies with operating conditions and environment.
CAUTION: Never start or operate with a closed suction valve. Never operate with a closed discharge valve.
CAUTION: Always provide adequate NPSHa (net positive suction head available). It is recommended to provide at least 2 feet (61 cm) above the NPSHr
(net positive suction head required).
CAUTION: If pump is used on variable speed drive, do not exceed the frequency for which the pump was designed (for example, if the pump is a 50 Hz
model, do not exceed 50 Hz)
.
CAUTION: Proper o-ring material must be chosen for the fluid being pumped. Improper material selection could lead to swelling and be a possible source
of leaks. This is the responsibility of the end user.
WARNING: The pump must be checked for leaks on a regular basis. If leaks are noticed, the pump must be repaired or replaced
immediately.
WARNING: The pump must be cleaned on a regular basis to avoid dust buildup greater than 5 mm.
WARNING: ATEX pumps must use a power monitor, flow switch, pressure switch or similar device to help protect against dry running, closed discharge
valve and decoupling. Any of these conditions could lead to a rise in surface temperature of the pump.
Temperature Classification
The surface temperature of the DB Series pumps depends upon the temperature of the fluid that is being pumped. The following chart lists different fluid
temperatures and the corresponding pump surface temperature.
Safety Precautions for ATEX Pumps
DB11/15 Capabilities
Maximum Working Pressure: 90 psi (6.2 bar) (models with o-ring)
Maximum Working Pressure: 50 psi (3.5 bar) (models with Gylon ® gasket)
Maximum Viscosity: 150 cP
Maximum Temperature: Polypropylene -180º F (82º C); PVDF – 220º F (104º C)
Note: Maximum temperature is application dependent.
Consult a chemical resistance guide or the chemical manu-
facturer for chemical compatibility and temperature limits.
Maximum Noise Level: 78 dBA (pump only)
Solids: Maximum particle size is 100 microns for slurries and 1/64” (.4 mm) for infrequent particles. Maximum hardness is 80 HS. Maximum concentration
is 10% by weight. If solids are being pumped, it is recommended that the pump have either ceramic or for best results, silicon carbide components. Pumping
solids may lead to increased wear.
Minimum Allowable Flow Rate:
Do not allow the flow rate to drop below the minimum flow rate listed in the chart below:
Model 3450 rpm 1725 rpm 2900 rpm 1450 rpm
DB11 4 gpm (.9 m 3 /hr) 2 gpm (.5 m 3 /hr) .76 m 3 /hr (3.4 gpm) .38 m 3/ hr (1.7 gpm)
DB15 5 gpm (1.1 m 3 /hr) 2.5 gpm (.6 m 3 /hr) .95 m 3 /hr (4.2 gpm) .48 m 3 /hr (2 gpm)
Maximum Allowable Motor Power:
Do not exceed the maximum power rating for the pump coupling.
Standard coupling for the DB11 is 6-pole; standard coupling for the DB15 is 8-pole.
6-pole coupling = 2 horsepower (1.5 kW)
8-pole coupling = 3 horsepower (2.2 kW)
10-pole coupling = 5 horsepower (4 kW)
CAUTION: Use of a power monitor is strongly recommended for pumps with ceramic, PTFE or silicon carbide bushings. The power monitor will stop
the pump and help prevent damage if the pump should run dry. ATEX certified pumps MUST use a power monitor
.
Fluid Temperature Maximum Surface
Temperature
Temperature
Class
Maximum Allowable
Surface Temperature
70º F (27º C) 131º F (55º C) T6 85º C
170º F (85º C) 168º F (76º C) T5 100º C
220º F (104º C) 183º F (84º C) T4 135º C