Circor HOUTTUIN 216 Series, Оригинальное руководство по установке, эксплуатации и обслуживанию

Страница: 32 / 84

Installation
30
216 Series Twin-Screw Pump -
Installation, Operation & Maintenance Manual
Allowable dial indicator values for alignment checks
NOTICE:
The specified misalignment values are valid only at operating temperature. For cold settings,
different values must be used to account for the expected thermal expansion. Failure to do so
can result in being unable to successfully perform hot alignment.
The driver shaft initial (cold) parallel vertical alignment setting should normally be lower than
the pump shaft (unless the pump operates at a high process temperature, see the next
section). Follow the driver manufacturer's recommendations.
When dial indicators are used to check the final alignment, the pump and drive unit are
correctly aligned when the conditions shown below are established:
Pump
running speed
Indicator maximum allowable Total Indicated
Reading (TIR) @ operating temperature
3600 RPM 0.05mm (0.002in)
1800 RPM 0.1mm (0.004in)
1200 RPM 0.15mm (0.006in)
0 to 900 RPM 0.2mm (0.008in)
Calculate the thermal expansion
Thermal expansion of the driver always has to be considered as drivers are foot mounted.
Additionally in cases where the operating temperature of the pump varies considerably from
ambient, the amount of thermal expansion in the pump/driver combination becomes important
for proper alignment of the coupling.
The following explanations and worked example illustrate the simplicity of these calculations
and the necessity that they be made.
The formula for thermal expansion is expressed as:
Thermal movement =
α
x
Δt
x ( machine foot to shaft centerline distance )
The coefficient of expansion
α
is specific to the material of construction expressed as a value
per degree temperature of rise.
The Houttuin 216 series pump may be supplied in the following materials of construction:
Generic Material Coefficient of thermal expansion
α
mm/mm/°C (in/in/°F)
Grey Cast Iron 10.8 x 10
-6
(6.0 x 10
-6
)