Thrush HVGTB User Manual

9636-0560

INSTALLATION

LOCATION

OPERATION & MAINTENANCE INFORMATION

FOR

MODEL HVGT & HVGTB IN-LINE CENTRIFUGAL PUMPS

MODEL HVGT & HVGTB

The Thrush In-Line Cen trifugal Pump has been carefully assembled and factory tested to provide
years of trouble-free service. In order to assure the service intended, the following information is
provided to enable proper installation, operation and maintenance of the HVGT / HVGTB pump. The
Thrush HVGT/ HVGTB pum p uses standard GTB replacement parts for easy parts replacement. The
motor and bearing assembly have sealed ball bearings and never have to be oiled o r greased. The
motor is also resilient mounted f or reliable quiet operation. The pump comes with the standard Type
21 seal, stainless steel shaft and external water slinger for added bearing assembly life in case o f seal
failure.

The pumps should be located as close to the liquid source as possible so that the suction line can be
short an d irect. 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 the drive.

Adequate provisions should be m ade for electrical wiring to the pump motor. A switch and overload
protection should be installed near the pump. The flexible electrical conduit should be used in
connecting motor wiring.

6/11

MOUNTING

PIPING

SUCTION PIPING

DISCHARGE PIPING

PRIMING THE PUMP

FLOODED SUCTION PRIMING

The pump will not operate satisfactorily until is is primed. All air must be expelled from the suction
piping and pump casing and replaced b y the liquid to be pumped. There are several m ethods of
priming pumps. The one selected will depend on the specific requ irements.

This method of priming a pump is relatively simple. Th e liquid source is located above the pump and
all that is necessary to prime the pump is to open the air vent valve or p lug in the pump casing and to
crack the isolating valve in the suction line. The suction line and pump should be filled slowly until a
steady stream of liquid is observed flowing from the air vent. After the pump is operating, it is
recomm ended that the air vent valve or plug be opened again to insure that all air has been expelled
from the pump casing.

Long radius elbows should be used in place of standard elbows wherever possible, becau se of their
superior flow characteristics. Elbows installed in any position a t the suction nozzle have a tendancy to
distribute the liquid unevenly in the impeller eye and may cause a reduction in capacity which creates
an undesirable thrust condition or creat noisy operat ion. 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.

The discharge piping diameter should be the same as, or larger than, the discharge nozzle diameter.
The size of the discharge pipe t o be used is dependent upon its application.
PROPER PIPING ALIGNMENT IS ESSENTIAL BEFORE CONNECTION IS MADE. PIPING
ALIGNMENT SHOULD NEVER BE ACHIEVED BY FORCE, THIS COULD PROCUCE STRA IN ON
THE PIPING AND TH E PUMP CASING. NOTE: Centrifugal pumps should never be started or run
dry. Operating a pump dry will cause scoring of the mechanical seals, resulting in pr emature

seal failure. To prevent the pump from being run dry, it should be primed before starting.

Thrush In-Line pumps con serve floor space, simplify piping and can be serviced without discon­necting piping. 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 HVGT SERIES PUM PS SHOULD ALWAYS BE CONNECTED TO TH E PIPING
RATHER TH AN TO THE PUMP CASING

. 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 perm it servicing of the pump without draining the entire
system. Make certain the space aroun d the pump is sufficient to give clearance for rem oving 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 pum p is concentrated at one point in the
piping.

The piping practices you follow will directly affe ct the efficiency and power consumption of your 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 INDEPENDENTL Y SUPPORTED NEAR THE PUMP. LIBERAL USE OF PIPE
HANGERS AND SUPPORT BLOCKS WI LL 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. All joints m ust be tight to maintain prime on the
pump.