Thrush TV2g In-Line User Manual

OPERATING AND MAINTENANCE INFORMATION

FOR TV2g IN-LINE CENTRIFUGAL PUMP

INSTALLATION

LOCATION

The pump should be located as close to the liquid source as possible so that the suction line can
be short and direct. It should be located in a clean, open area, where it is easily accessible for
inspection, lubrication and repair. Pumps installed in dark, dirty areas or in cramped locations are
often neglected which can result in premature failure of both the pump and driver.

Adequate provisions should be made for electrical wiring to the pump motor. A switch and
overload protection should be installed near the pump unless it is impractical. The flexible
electrical conduit should be connected to the motor in such a way as to preclude the possibility of
moisture entering the conduit or the motor and causing short circuits.

MOUNTING

Thrush In-line pumps conserve floor space, simplify piping, and can be serviced without
disconnecting piping. They are designed to be installed in either the vertical or horizontal
position. The proper installation of these pumps is to install them as “a part of the piping”. The
pumps must be free to “travel” with the expansion and contraction of the piping. In-line
installation eliminates the problems normally encountered in aligning piping to a base mounted
unit. SUPPORT OF THE TV2g SERIES PUMPS SHOULD ALWAYS BE CONNECTED TO THE
PIPING RATHER THAN TO THE PUMP CASING. (See Figure 2). The line-mounted feature
eliminates the need for installing flexible pipe connectors at either the pump suction or discharge.
Isolating valves should be installed at both the pump suction and discharge to permit servicing of
the pump without draining the entire system. Make certain the space above the pump is sufficient
to give clearance for lifting the pump assembly from the casing. Also, the space around the pump
should be large enough for general accessibility and ventilation. The same criteria and formula
for selecting piping supports are used with the additional consideration that the weight of the
pump is concentrated at one point in the piping.

PIPING

The piping practices followed will directly affect the efficiency and power consumption of the
pump. Pay particular attention to the seemingly insignificant details involved in piping for they
make the difference between a good and bad installation. BOTH THE SUCTION AND THE
DISCHARGE PIPING SHOULD BE INDEPENDENTLY SUPPORTED NEAR THE PUMP.
LIBERAL USE OF PIPE HANGERS AND SUPPORT BLOCKS WILL PREVENT EXCESSIVE
STRAIN ON THE PUMP CASING AND ON THE PIPE JOINTS. The suction diameter should be
at least the same diameter as the suction nozzle on the pump and preferably larger. Use of a
smaller diameter pipe will result in loss of head due to friction. All joints must be tight to maintain
prime on the pump.

SUCTION PIPING

Long radius elbows should be used in place of standard elbows wherever possible because of
their superior flow characteristics. Elbows should not be used at the suction nozzle, but if it is
unavoidable, long radius elbows should be used. Elbows installed in any position at the suction
nozzle have a tendency to distribute liquid unevenly in the impeller eye and may cause reduction
in capacity, create an undesirable thrust condition, or create noisy operation. Eccentric redu cers
should be installed directly at the suction nozzle, with the taper at the bottom to prevent air
pockets from forming. Straight taper reducers should never be used in a horizontal suction line
because of the air pocket that is formed at the leg of the reducer and the pipe (Refer to Figure 3).

DISCHARGE PIPING

The discharge pipe diameter should be the same as, or larger than, the discharge nozzle
diameter. The size of the discharge pipe to be used is dependent upon its application.

Long radius elbows should be used in the discharge piping as well as in the suction piping to
prevent excessive head loss due to friction. Whenever possible, elbows should not be installed
directly at the discharge nozzle as the turbulence created by the elbow will affect pressure gauge
readings.

An increaser should be installed at the discharge nozzle if larger diameter discharge piping is
used. Straight taper increasers and/or reducers are satisfactory in discharge applications.

PROPER PIPING ALIGNMENT IS ESSENTIAL BEFORE CONNECTION IS MADE. PIPING
ALIGNMENT SHOULD NEVER BE ACHIEVED BY FORCE. THIS COULD PRODUCE STRAIN
ON THE PIPING AND THE PUMP CASING. PROPER SUPPORTS SHOULD BE INSTALLED
FOR THE PIPING TO KEEP ITS WEIGHT OFF THE PUMP CASING.