Dresser RCS Руководство по эксплуатации - Страница 4

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1. Maintenance/Replacements

Two methods may be used to handle a blower without

base. One is to use eyebolts screwed into the top of the

headplates. Test them first for tightness and fractures by

tapping with a hammer. In lifting, keep the direction of

cable pull on these bolts as nearly vertical as possible. If

eyebolts are not available, lifting slings may be passed

under the cylinder adjacent to the headplates. Either

method prevents strain being placed on the extended

drive shaft.

When blower is furnished mounted on a baseplate,

with or without a driver, use of lifting slings passing

under the base flanges is required. Arrange these slings so

that no strains are placed on the blower casing or mount-

ing feet, or on any mounted accessory equipment. DO

NOT use the eyebolts in the top of the headplates.

Before starting the installation, remove plugs, covers

or seals from blower inlet and discharge connections and

inspect the interior completely for dirt or foreign material.

If cleaning is required, finish by washing the cylinder,

headplates and impeller thoroughly with a petroleum sol-

vent such as DuPont Triclene D. After this, turn the drive

shaft by hand to make sure that the impellers turn freely

at all points. Anti-rust compound on the connection

flanges and drive shaft extension may also be removed at

this time with the same solvent. Then cover the flanges

again to keep out dirt until ready to connect the air pip-

ing. Washing out is not required if the interior is found to

be clean. The corrosion inhibitor used will vaporize and

disappear during operation.

Care, plus consideration of all possible problems, will

pay dividends when arranging the blower mounting. This

is especially true when the blower is a "bare" unit, fur-

nished without a baseplate. The convenient procedure

may be to mount such a unit directly on a floor or small

concrete pad, but this generally produces least satisfac-

tory results. It definitely causes the most problems in

leveling and alignment.

Direct use of structural framing members is also not a

recommended mounting.

unavoidable, the members

must be rigidly reinforced when part of a building, and

spring type mountings should not be used. Noise

transmission can usually be reduced by use of a cork in-

sulating pad 1 to 2 inches (25 to 50 mm) thick. The pad

should be supported by a full steel plate attached to the

structure, with a rigid concrete slab laid on top of the cork

to carry the blower and driver.

For a blower without base, it is recommended that a

well anchored and carefully leveled steel or cast iron

mounting plate be provided at the installation point. The

plate should be about 1 inch (25 mm) thick, with its top

surface machined flat, and large enough to provide level-

ing areas at one side and one end after the blower is

mounted. It should have properly sized studs or tapped

holes located to match the blower foot drilling. As an

alternative, smaller plates at each end of the blower may

be used. This is more complicated usually makes leveling

more difficult, and can produce twist or strains in the

blower. Use of a high quality machinist's level is impor-

tant.

With the mounting plate in place and leveled, set the

blower on it without bolting and check for rocking.

it is

not solid, determine the total thickness of shims required

under one foot to stop the rocking. Place half of this under

each of the diagonally-opposite short feet, and tighten the

mounting studs or screws. Rotate the drive shaft to make

sure the impellers still turn freely.

the blower is to be

direct coupled to a driving motor, consider the height of

the motor shaft and the necessity for it to be aligned very

accurately with the blower shaft. Best arrangement is for

the blower to be bolted directly to the mounting plate

while the driver is on shims of at least 1/8 inch (3 mm)

thickness. This allows adjustment of motor position in

final shaft alignment by varying the shim thicknesses.

When blower and driver have been factory mounted

on a common baseplate, the assembly will have been pro-

perly aligned and is to be treated as a unit for leveliIJ.g pur-

poses. Satisfactory installation can be obtained by setting

the baseplate on a concrete slab that is rigid and free of

vibration, and leveling the top of the base carefully in two

directions so that it is free of twist. The slab must be pro-

vided with suitable anchor bolts. The use of grouting

under and partly inside the base, after it has been careful-

ly leveled by shimming, is recommended.

It is possible for a base-mounted assembly to become

twisted during shipment, thus disturbing the original

alignment. For this reason, make the following checks

after the base has been leveled and bolted down. Discon-

nect the drive and rotate the blower shaft by hand. It

should turn freely at all points. Loosen the blower foot

hold-down screws and determine whether all feet are even-

ly in contact with the base. If not, insert shims as required

and again check for free impeller rotation. Finally, if

blower is direct coupled to the driver, check shaft and

coupling alignment carefully and make any necessary cor-

rections.

In planning the installation, and before setting the

blower, consider how piping arrangements are dictated by

the blower design and assembly. RCS blowers have rever-

sible rotation.

Standard arrangement on vertical units has the drive

shaft at the top. Horizontal units' standard arrangement

has the drive shaft at the left.

When a blower is DIRECT COUPLED to its driver,

the driver RPM must be selected or governed so as not to

exceed the maximum speed rating of the blower. Refer to

LIMITATIONS for allowable speeds for various blower

sizes. A flexible type coupling should always be used to

connect the driver and blower shafts.

Coupling halves must be accurately aligned, and a

sufficient gap between shaft ends provided so that side

strains and end thrust on either shaft are avoided or

minimized. This will require considerable care in the

mounting of the driver. The two shafts must be in as near

perfect alignment in all directions as possible, and the gap

must be established with the motor armature on its elec-

trical center if end play exists.

The following requirements for a good installation are

recommended. Coupling halves must be, fitted to the two

shafts so that only light tapping is required to install

them. Maximum deviation in offset alignment of the

shafts should not exceed .005" (.13 mm) total indicator

reading, taken on the two coupling hubs. Maximum devia-