Dresser RCS Manual de instruções - Página 3

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1. Maintenance/Replacements

under standard atmospheric conditions. Do not exceed any

one of these limits.

Example: The listed maximum allowable temperature

rise (increase in ail' temperature between inlet and

discharge) for any particular blower may occur well before

its maximum pressure or vacuum rating is reached. This

can easily occur at high altitude or at very low speed.

Temperature rise then is the limiting condition. In other

words, the operating limit is always determined by the max-

imum rating reached first. It can be anyone of the three:

pressure, temperature or speed.

Be sure to arrange connections or taps for thermometers

and mercury type pressure or vacuum gauges at or neal'

the inlet and discharge connections of the blower. These

along with a good tachometer, will enable periodic checks

of operating conditions to be made easily.

PRESSURE-On pressure service; the pressure rise

(between blower inlet and discharge) must not exceed the

figure listed for the specific blower frame size concerned.

Also, in any system where the blower inlet is at a positive

pressure above atmosphere, the discharge pressure must

never exceed 25 PSI (172 kPa) gauge regardless of blower

size.

On vacuum service, with the discharge going to at-

mospheric pressure, the inlet suction or vacuum must not

be greater than values listed for the specific frame size.

TEMPERATURE-RCS blower frame sizes are ap-

proved only for installations where the following tempera-

ture limitations can be maintained in service.

A. Measured temperature rise must not exceed listed values

when the inlet is at ambient temperature. Ambient is

considered as the general temperature of the space

around the blower. This is not outdoor temperature

unless the blower is installed outdoors.

B. If inlet temperature is higher than ambient, the listed

allowable temperature rise values must be reduced by

of the difference between the actual measured inlet

temperature and the ambient temperature.

C. An average temperature between inlet and discharge up

to 250°F. (121°C).

SPEED RANGE-RCS blowers may be operated at

speeds up to the maximum listed for the sizes. They may

be direct coupled to suitable constant speed drivers if

pressure/temperature conditions are also within limits. At

low speeds, excessive temperature rise may be the limiting

factor as noted in the preceding example.

Table 1-Maximum Allowable Operating Conditions

Frame Speed

Press. Rise

Inlet Vac. Temp. Rise

Size

RPM

PSI

(kPa)

In. (kPa)

Hg.

404

3820

(104)

(50)

275

(153)

406

3820

(104)

(50)

275

(153)

409

'3820

(104)

(50)

275

(153)

412

3820

(104)

(50)

275

(153)

418

3820

(104)

(50)

275

(153)

616

2860

(69)

(50)

230

(128)

624

2820

(69)

(50)

230

(128)

INSTALLATION

Roots RCS blowers are internally and externally

treated after factory assembly to protect against normal

atmospheric corrosion before installation. The maximum

period of internal protection is considered to be one year

under average conditions, if closing plugs or seals are not

removed. Protection against chemical or salt water at-

mosphere is not provided. Avoid opening the blower until

ready to start installation, as protection will be lost quick-

ly by evaporation.

If there is to be an extended period between installa-

tion and start up, the following steps should be taken to

insure corrosion protection:

1. Coat internals of cylinder, gearbox and drive

end bearing reservoir with Motorstor or

equivalent. Repeat once a year or as conditions

may require. Motorstor is oil soluble and does not

have to be removed before lubricating. If desired,

Motorstor may be removed from within the

cylinder shortly before start up by spraying a fine

mist of petroleum solvent through the blower

while it is running at a slow speed with open inlet

and discharge, or it can remain in the blower if it is

not harmful to the operation of the connected

system. Motorstor is a product of Daubert

Chemical Co., 2000 Spring Rd., Oak Brook, Ill.

60521.

2. Paint shaft extension, inlet and discharge flanges,

and all other exposed surfaces with Nox-Rust

X-145'or equivalent.

3. Seal inlet, discharge, and vent openings. It is not

recommended that the unit be set in place, piped to

the system, and allowed to remain idle for extend-

ed periods. If any part is left open to the at-

mosphere, the Motorstor vapor will escape and

lose its effectiveness.

4. Units are not to be subjected to excessive vibra-

tion during storage. If stored outdoors, provide

coverage such as a tarpaulin or lean-to.

5. Rotate drive shaft three or four revolutions every

two weeks.

6. Prior to start up, remove flange covers on both in-

let and discharge and inspect internals to insure

absence of rust. Check all internal clearances. Also,

at this time, remove gearbox and drive end bearing

cover and inspect gear teeth and bearings for rust.

Because of the completely enclosed blower design,

location of the installation is generally not a critical mat-

ter. A clean, dry and protected indoor location is pre-

ferred. However, an outdoor or wet location will normally

give satisfactory service. Important requirements are

that the correct grade of lubricating oil be provided for ex-

pected temperatures, and that the blower be located so

that routine checking and servicing can be handled

conveniently after installation. Effect of the location on

driver and accessory equipment must also be considered.

Supervision of the installation by a Factory Service

Engineer is not usually required for these blowers.

Workmen with experience in installing light-medium

weight machinery should be able to produce satisfactory

results. Handling of the equipment needs to be ac-

complished with care, and in compliance and safe prac-

tices. Blower mounting must be solid, without strain or

twist, and air piping must be clean, accurately aligned and

properly connected.