BLACKMER SNP1.25, Installation, Operation And Maintenance Instructions

104-A00    page 4/16 

INSTALLATION 

PUMP MOUNTING 

A solid foundation reduces noise and vibration, and will 
improve pump performance. On permanent installations it is 
recommended the pumping unit be secured by anchor bolts 
as shown in Figure 2. This arrangement allows for slight 
shifting of position to accommodate alignment with the 
mounting holes in the base plate. 

Figure 2 - Pipe Type Anchor 

Bolt Box 

For new foundations, it is 
suggested that the anchor bolts 
be set in concrete. When 
pumps are to be located on 
existing concrete floors, drill 
holes into the concrete to hold 
the anchor bolts. 

When installing units built on channel or structural steel type 
bases, use care to avoid twisting the base out of shape when 
anchor bolts are tightened. Use shims under the edges of the 
base prior to tightening the anchor bolts to level the base and 
prevent distortion. 
 

COUPLING ALIGNMENT 

The pump must be directly coupled to a gear and/or driver 
with a flexible coupling.  Verify coupling alignment after 
installation of new or rebuilt pumps.  Both angular and 
parallel coupling alignment MUST be maintained between the 
pump, gear, motor, etc. in accordance with manufacturer’s 
instructions.  See Figure 3. 

1.  Parallel alignment:  The use of a laser alignment tool or 

dial indicator is preferred.  If a laser alignment tool or dial 
indicator is not available, use a straightedge.  Turn both 
shafts by hand, checking the reading through one 
complete revolution.  Maximum offset must be less than 
.005" (.127 mm). 

2.  Angular alignment:  Insert a feeler gauge between the 

coupling halves.  Check the spacing at 90° increments 
around the coupling (four checkpoints).  Maximum 
variation must not exceed .005" (.127 mm).  Some laser 
alignment tools will check angular alignment as well. 

3.  Replace the coupling guards after setting alignment. 

Figure 3 – Alignment Check 

Do not operate 

without guard 

in place 

Operation without guards in place can 
cause serious personal injury, major 
property damage, or death. 

PUMP ROTATION 

NOTICE: 

Confirm correct pump rotation by checking the pump 
rotation arrows respective to piping flow direction.  Do 
not operate the pump in reverse rotation to reverse the 
direction of flow. 

1.  Determine direction of flow where the pump will be 

installed. 

2.  Confirm pump is installed in piping so that the flow will 

pass through the pump from inlet to outlet.  The inlet of 
the pump has “INLET” cast in the cylinder and the outlet 
has “OUTLET” cast in the cylinder. 

3.  Briefly “jog” pump with pump driver. Check rotation of 

pump driver with respect to rotation arrow on pump. 

A right-hand pump rotates clockwise with the intake on the 
right side, when viewed from the driven end. 

A left-hand pump rotates counterclockwise with the intake on 
the left side, when viewed from the driven end. 
 
 

TO CHANGE PUMP ROTATION 

To reverse rotation, the pump must be disassembled then 
reassembled with the shaft on the opposite side of the pump.  
See the ‘Maintenance’ section for instructions. 

 
 
CHECK VALVES 

The use of check valves or foot valves in the supply tank is 
not recommended with self-priming, positive displacement 
pumps.  

If the possibility of liquid backflow exists when the pump is 
off, a check valve in the pump discharge piping is 
recommended because the pump can motor in the reverse 
rotation and create undue stress on all attached components.  
Never start a pump when it is rotating in the reverse rotation 
as the added starting torque can damage the pump and 
related equipment.  If a check valve is used, install it at the 
pump discharge. 
 
 

OPTIONAL JACKETED HEADS

Hot oil or steam can be circulated through jacketed heads by 
connections at the jacket pipe plugs (73B) for heating highly 
viscous liquids, or to "thaw out" liquids which have congealed 
in the pumping chamber and packing area.  Refer to the 
'Technical Data' table on page 2 for the maximum allowable 
steam pressure. 

Make sure heat is applied early enough to sufficiently thin the 
liquid before starting the pump.  Liquids that congeal in the 
relief valve chamber will make the valve inoperative.  
Insulation of the pump with sufficient heat to the jackets will 
usually thin the liquid in the relief valve chamber.  Take 
precautions to ensure the valve has free movement.  It is 
advisable to start the pump with an open discharge.  

Drain the pump of all water when there is a possibility of 
freezing.  On models which have the steam connections on 
the vertical center line, make the lower connection the outlet 
so the water can be drained off.  Models which have the 
steam connections on the side also have a bottom drain plug.