1-Attachment 1 - Circular H Drive Unit Replacement Manual.pdf

.081DR/02-15

CIRCULAR “H” DRIVE UNIT

REPLACEMENT

MANUAL .081DR

TABLE OF CONTENTS

SECTION PAGE

INSTALLATION 1-0

OPERATION 2-0

MAINTENANCE 3-0

OVERHAUL/SPARE PARTS 4-0

VENDOR INFORMATION 5-0

NOTE: DISASSEMBLY AND REMOVAL OF THE EXISTING

DRIVE SHOULD BE DONE WITH EXTREME CARE.

REMOVE COMPONENTS IN A FASHION TO NOT

THE CENTER PIER.

DO NOT KNOCK THE CENTER PIER OUT OF

PLUMB.

INSTALLATION

.081DR/02-15 1-0

SECTION 1 CONTENTS

ITEM PAGE

SAFETY PRECAUTIONS 1-1

STANDARD ERECTING PRACTICES 1-4

FASTENER INSTALLATION 1-5

REMOVAL OF EXISTING EQUIPMENT 1-7

ERECTOR'S CHECKLIST 1-7

FIELD BOLTS 1-8

SITE PREPARATION 1-8

CENTER PIER ADAPTER, CENTER CAGE ADAPTER AND BRIDGE

MODIFICATIONS (IF FURNISHED) 1-8

SETTING THE DRIVE ON THE CENTER PIER 1-8

ASSEMBLING THE CENTER CAGE TO DRIVE 1-10

BRIDGE INSTALLATION 1-10

DRIVE CHAIN INSTALLATION 1-12

ADJUSTING FOR TRUE PLANE ROTATION 1-13

DRIVE UNIT PROTECTION FOR BLAST CLEANING 1-16

PREPARING DRIVE UNIT FOR OPERATION 1-18

TORQUE OVERLOAD MICROSWITCH DEVICE 1-19

TOOLS REQUIRED TO SET MICROSWITCHES 1-19

PROCEDURE FOR SETTING THE MICROSWITCH GAPS 1-22

ZEROING THE DIAL INDICATOR 1-22

WHEN A TORQUE OVERLOAD CONDITION OCCURS 1-23

.081DR/02-15 1-0a

ITEM PAGE

DISASSEMBLY AND SPRING PLATE INSPECTION 1-24

REASSEMBLY 1-24

OVERLOAD HOUSING VENT 1-24

TORQUE OVERLOAD DEVICE 1-25

PRE-OPERATIVE CHECK 1-26

TORQUE TESTING PROCEDURE 1-26

.081DR/02-15 1-1

CIRCULAR “H” DRIVE UNIT REPLACEMENT

The instructions and recommendations in this manual are intended to assist the Erecting Contractor, the Plant Operator and Maintenance Personnel in the drive replacement only.

Refer to your original manual for all other items.

Because plant design varies according to Engineer's specifications, State and Local codes and Insurance and Underwriters' requirements, the instructions are necessarily general in nature. If more specific information is required or if questions of a technical nature arise, please contact your local Evoqua representative or the factory. (See GENERAL INFORMATION section.)

Recommendations on the storage of this equipment are included in the GENERAL INFORMATION section of this manual.

All drawings submitted are to be found in the manual pocket.

SAFETY PRECAUTIONS

General Safety Precautions to be used in erecting, operating and maintaining this equipment are included in the GENERAL INFORMATION section of this manual.

Precautions that are specific to Circular Collectors are included within the text of this manual. A caption of CAUTION, WARNING or DANGER indicates the severity of the hazard and a graphic symbol indicates the nature of the hazard. Recommended precautions are included in the text, adjacent to the symbol.

The primary hazards associated with installing circular sludge collection equipment are identified below.

HANDLING HEAVY EQUIPMENT

Circular collectors have large and heavy parts, which must be lifted and located during assembly.

Cranes, hoists and lifting gear must have a load capacity greater than the loads to be lifted. Lifting points should be selected with care and lifting harness should be stabilized.

Avoid hand lifting of heavy parts.

.081DR/02-15 1-2

PERSONNEL PROCEDURES

Installation procedures will require working in elevated positions.

Secure ladders before use. Safety harness should be worn when there is danger of falling. Do not use bridge without handrails in place. Do not work outside of the handrails.

The access area for drive maintenance is below the bridge deck level.

The difference in level will depend on the bridge design. A falling hazard exists. Use caution when in or near the access area.

FIRE HAZARDS

The use of welding equipment and cutting torches may be required in the erection of Circular Collectors. Some components may be made from polymeric materials. These materials are combustible. Metallic equipment is frequently coated with combustible substances. A fire can grow quickly, sometimes emitting toxic gases. Move combustible materials away from an area in which welding or cutting is being done. Keep combustible materials away from heat and open flame. If a fire occurs, do not breathe fumes.

Fire extinguishers and plant water must be available in the area. Workmen must be able to leave the tank quickly.

.081DR/02-15 1-3

WELDING HEALTH HAZARDS

Since Evoqua does not know what welding processes and filler materials will be used for field welding, the following general welding health hazard data should be conveyed to welding personnel.

Arc rays can injure eyes and burn skin. Heat rays (infrared radiation from flame or hot metal) can injure eyes.

Overexposure to electric arc welding or oxy-fuel gas processes may create one or more of the following hazards. Carbon Steels - Excessive inhalation of metallic fumes and dusts may result in irritation of eyes, nose and throat. Stainless Steels - Cancer hazard (contains chromium and nickel). Excessive inhalation of metallic fumes and dusts may cause sensitation dermatitis, inflammation and/or ulceration of the upper respiratory tract and possible cancer of nasal passages and lungs.

Electric shock can cause injury or death.

Noise can damage hearing.

Read and understand the welding materials manufacturer's instructions and precautionary label on the product being used. For further health hazard details, consult the welding materials manufacturer's Material Safety Data Sheets.

GUARDS

Guards cover several points on Circular Collectors to prevent personal injury from moving parts. If guards are not in place during installation procedures, use caution when operating equipment and put guards in place when these procedures are complete.

.081DR/02-15 1-4

STANDARD ERECTING PRACTICES

FABRICATED STEEL EQUIPMENT

Fabricated steel equipment, manufactured by Evoqua, should pose no unusual erecting problems. Due to the nature of such equipment and the condition of the containing structure (over which we have no control), a reasonable amount of fit-up and adaptation is considered standard erection practice. The use of tools, such as "come-alongs", welding and cutting torches, drift pins and reamers, is to be expected.

When new units are tied into existing units, a major amount of fit-up may be required.

Accumulated tolerances in the existing equipment usually require detail fit-up for tie-in and alignment.

Standard erecting practice, as defined by the AISC "Code of Standard Practice (3/05)," Section 7.14., specifically states that:

“The correction of minor misfits by moderate amounts of reaming, grinding, welding or cutting, and the drawing of elements into line with drift pins, shall be considered to be normal erection operations. Errors that cannot be corrected using the foregoing means, or that require major changes in member or connection configuration, shall be promptly reported to the Owner’s designated representatives for design and construction and the Fabricator by the Erector, to enable the responsible entity to either correct the error or approve the most efficient and economical method of correction to be used by others.”

If a problem is traceable to fabrication or engineering, backcharges for replacing or correcting materials require prior written approval of an authorized Evoqua representative and will only be considered with prompt, complete cost documentation based on standard, direct field labor hours and material. Profit, overhead and all other charges will not be allowed. Payment may be refused for corrective work that is done without the above-mentioned approval and documentation.

.081DR/02-15 1-5

FASTENER INSTALLATION

It is important to install fasteners so that they adequately connect the parts they are to join without loosening and without causing damage to the parts in the joint. In joints where there is a possibility of fatigue, or where a connection has been designed as slip-critical, proper pretension of the fastener must be provided.

Evoqua equipment is manufactured from traditional materials (metals) as well as materials that are on the leading edge of technology. Using the following instructions for fastener tightening will insure that your equipment is properly installed.

METAL TO METAL CONTACT

Evoqua uses common bolts and screws in the majority of joints where all plies in the joint are metal. Common fasteners are made from materials such as ASTM A307 steel and SAE grade 2 steel. In applications where corrosion is a concern, fasteners made from 300 series stainless steel are used. For these joints, the fasteners can be installed in the “snug-tightened” condition. From the Specification for Structural Joints Using ASTM A325 or A490 Bolts (June 23, 2000): “The snug-tightened condition is the tightness that is attained with a few impacts of an impact wrench or the full effort of an ironworker using an ordinary spud wrench to bring the connected plies into firm contact.”

Unless a connection is made up with High strength bolts (A325, A490 or SAE grade 5 or grade 8) no pre-load is required.

For joints made up with high strength fasteners, the Research Council on Structural Connections (RCSC) of the American Institute of Steel Construction (AISC) recognizes three types of joints, snug-tight, pre-tensioned, and slip-critical. If a joint was designed as slip-critical, or requiring pre-tension, it will be indicated as so on the drawings. Use the procedures found in Section 8 of the Specification for Structural Joints Using ASTM A325 or A490 Bolts (2000, Research Council on Structural Connections c/o AISC) to properly preload the fasteners in the joint if preload is required.

.081DR/02-15 1-6

NON-METAL CONTACT

For joints that involve one or more items that are not made from metal, there may be special instructions for the tightening of fasteners. Carefully read the instructions in the Operation and Maintenance Manual and the notes on the drawings where non-metal parts are used. There may be special fastener torque tables or other notes about making up the connection.

If the fasteners in a connection that involves a non-metal part are over torqued, there is the likelihood that the non-metal parts will be deformed or put into a failure mode.

Because of the tendency of non-metal parts to exhibit high rates of material creep under load, there may also be requirements for retightening the fasteners after a period of time.

Follow their instructions carefully.

If there are no specific instructions for tightening a fastener in a joint that has one or more non-metal parts, then it is sufficient to tighten the fastener until the parts are in complete contact, the fastener is tight and there is no deformation of the parts or of any washers that are included.

ANCHORS

Evoqua supplies many types of concrete anchors with our equipment. When a proprietary anchor is provided, whether it is adhesive style, wedge style or other, follow the anchor manufacturer’s instructions to torque the nuts or bolts used with these anchors.

.081DR/02-15 1-7

REMOVAL OF EXISTING EQUIPMENT

Carefully remove the existing walkway bridge. Care should be used in disconnecting power at both the tank wall and at the existing drive unit. The existing bridge should be placed on blocks in an area where cutting and welding can be exercised. This may be required to convert the existing bridge to the new drive unit.

Block up the existing mechanism at the floor level. Use several blocking points at the bottom of the cage and at the tip of the truss arm. Secure the upper cage to the center pier with come-alongs to prevent tipping once drive is removed.

The existing drive unit can be unbolted from the existing center pier, center cage and properly disposed of. Note, during the removal, care should be used not to bump or put excessive pressure on the center pier that may knock it out of plumb. Do not tip the drive unit, as it contains oils that can spill out.

Review erection drawings. If existing center pier bolts are to be reused, clean up the threads and chip out existing grout, if any. Follow erection drawings for mounting of center pier adapter, center cage adapters and walkway bridge modifications.

ERECTOR'S CHECKLIST

If your contract includes a pre-start check by an Evoqua field service technician, the following should be completed before arranging the site visit:

1. Re-install the entire mechanism, including bridge handrail and grating.

2. DO NOT grout under the drive at this time.

3. DO NOT operate the drive under power. This will damage the drive since there is

NO oil in either the worm gear or the spur gear housings. The protective overloads are not set at the factory. They will be set by the technician.

4. A surveying level will be required for the technician to check the horizontal plane of rotation.

The technician will check the equipment installation. After the equipment has been checked, the drive should be grouted.

A final mechanical check will be made by the Evoqua technician. Permanent power will be required along with connections made to the torque overload switches. It is MANDATORY that the overloads be in service at this time. If a torque test is to be performed, the tank needs to be cleared of all debris. A witness will be needed for the test. If required, the equipment will be certified by the Field Service Manager after the technician's report has been submitted.

Operation and maintenance instructions will also be provided at this time.

.081DR/02-15 1-8

FIELD BOLTS

Clarifiers utilize a hardware kit that contains the usual and customary hardware for a standard mechanism. Please note that some of the connections supplied in this kit may not be required on the furnished mechanism. The kit also contains hardware unique to the furnished mechanism. This kit is ordered from the Field Connection Drawings, located in this manual. The kit can be furnished from several different suppliers and can arrive at the job site in multiple shipments, usually at a different time than the equipment. The contractor should be aware of this and set aside a safe storage area for the hardware until it is required for erection.

SITE PREPARATION

Before actual erection of equipment has begun, a thorough inspection of the site is necessary. Evoqua assumes no responsibility for site preparation. The site should be cleared of all excess material to allow for safe and easy movement of the erection crew and their equipment. All foundation anchor bolts and other steel work embedded in concrete must be checked for cleanliness and accuracy of location. Continued reference to General Assembly Drawings and/or Anchor Bolt Layout Drawings will insure accuracy when equipment is erected. In the event of an error in location of the steel work or anchor bolts, they must be correctly positioned by the party(s) responsible before erection has begun.

If stainless steel bolts and nuts are used in the installation of this equipment, the bolt threads should be coated with a non-seizing compound such as "Never-Seez" or an equivalent.

CENTER PIER ADAPTER, CENTER CAGE ADAPTER AND BRIDGE

MODIFICATIONS (IF FURNISHED)

Follow erection drawings for mounting of center pier adapter, center cage adapters and walkway bridge modifications.

SETTING THE DRIVE ON THE CENTER PIER

Run a leveling nut and washer down each stud on the top flange of the center pier or adapter. The washers are to be at the "Bottom of Drive Elevation" shown on the General Arrangement Drawing. Set with a machinist's level and straight edge long enough to reach diametrically opposed washers.

.081DR/02-15 1-9

Orient the drive unit with respect to the bridge centerline at the tank wall as shown on the General Arrangement Drawing. Lower the drive onto the center pier leveling washers.

Check to see that all washers bear against underside of the drive base. Run a washer and full hex nut down each projecting stud and turn the nuts finger-tight. The drive elevation may have to be altered in subsequent final adjusting.

DO NOT GROUT THE DRIVE UNTIL THE ASSEMBLED MACHINERY HAS

BEEN ADJUSTED TO RUN IN A TRUE PLANE.

Figure 1

.081DR/02-15 1-10

ASSEMBLING THE CENTER CAGE TO DRIVE

Lift the center cage up and secure to the final drive. Hand tighten the nuts at this time.

NOTE: Standard cage lengths are detailed and fabricated in one inch increments. Shim packs, for the cage to drive connection, have been furnished to compensate.

Shim to obtain proper clearance between scraper blades and the finished floor and to obtain cage concentricity.

NOTE: Do not grout under final drive at this time. The unit must first be entirely assembled, statically balanced and then adjusted to rotate in a true horizontal plane before grouting in the drive. These procedures are found in subsequent sections of this manual.

BRIDGE INSTALLATION

There are several types of access bridges that can be furnished depending on the individual unit's requirements.

BEAM BRIDGE WITH OR WITHOUT PLATFORM

Using a transit, sight in the center of drive, center pier and center pier anchors. Carry this to the tank wall; locate and install bridge anchors. After anchors have cured, level and adjust the bridge base plate to the correct elevation. Place the bridge slide plate over the base plate. Using care not to knock the center pier out of plumb, install bridge onto the drive and tank wall slide plates. Install bolts at the drive and pipe spacers with nuts and washers at the wall anchors.

TRUSS BRIDGE WITHOUT PLATFORM

Install as per the beam bridge instructions listed above. Check Field Bolt Connection Drawing for plate washer requirements.

TRUSS BRIDGE WITH PLATFORM

Using a transit, sight in the center of drive, center pier and center pier anchors. Carry this to the tank wall; locate and install bridge anchors. After anchors have cured, level and adjust the bridge base plate to the correct elevation. Place the bridge slide plate over the base plate. Using care not to knock the center pier out of plumb, install center platform to drive using the required hardware and plate washers as indicated on the Field Connection Drawing. Install truss over slide plates and bolt to platform.

.081DR/02-15 1-11

TRUSS BRIDGE WITH WELL SUPPORTING PLATFORM

Using a transit, sight in the center of drive, center pier and center pier anchors. Carry this to the tank wall; locate and install bridge anchors. After anchors have cured, level and adjust the bridge base plate to the correct elevation. Place the bridge slide plate over the base plate. Using care not to knock the center pier out of plumb, install center platform to drive using the required hardware and plate washers as indicated on the Field Connection Drawing.

H40 SERIES CLARIFIER ONLY: Install truss over slide plates and bolt to platform. The well support beams can then be mounted to the platform/bridge.

H60 SERIES CLARIFIER ONLY: After installing the platform, mount the influent well support beams. Bolt platform supports to well support beams before installing the truss bridge.

No matter which type of bridge your unit is using, the following information will apply to the installation.

1. The bridge is rigidly secured to the drive unit/platform, but has a sliding "expansion" joint at the tank wall. The wall anchors must have pipe spacers installed to prevent binding of the bridge during expansion/contraction. Insure there is sufficient space at end of bridge for expansion. If, due to misalignment of the anchor bolts, sufficient room does not exist, then the slotted holes will have to be enlarged. If stairs or other appurtenances are attached to the bridge, then provisions for expansion/contraction must be made by the supplier of those items.

The bridge must be level within +/- 1/4" (6 mm) and the bridge beams/chords should be level to each other within +/- 1/8" (3 mm).

2. Bridges with Floor Plate. Floor plates should be laid on bridge loose per item numbers indicated on the General Arrangement Drawing and gaps adjusted for even spacing. The plates are furnished with a standard hole spacing to minimize field drilling of attachment holes. It is anticipated some field drilling will be required.

Contractor is to install minimum amount of clips required to secure floor plate and eliminate possible trips. If required, floor plate can be bolted directly to bridge structure, but should be limited to one connection per plate so as not to inhibit expansion/contraction of floor plate.

3. Bridges with Grating. Grating panels should be laid on bridge loose per item numbers indicated on the General Arrangement Drawing and gaps adjusted for even spacing. Fasten with clips and stainless steel self-drilling screws.

.081DR/02-15 1-12

DRIVE CHAIN INSTALLATION

Proper installation of power drive chains is important.

The correct amount of slack is essential to the proper operation of chain. See Figure 2.

Unlike belts, chain requires no initial tension and should not be tightened around the sprockets. Properly adjusted chain drive should permit slight flexure by hand in the slack strand.

When chain is too tight, the working parts carry a much heavier load than is necessary.

This causes rapid chain wear because of increased pressures in the joints. In addition, this condition overloads and accelerates wear in the shaft bearings.

Check the alignment of sprockets with a straight edge applied to the machined surface of the sprockets.

CW COLLECTOR ROTATION

Figure 2

.081DR/02-15 1-13

ADJUSTING FOR TRUE PLANE ROTATION

Reinstall scraper arms, influent well, skimmer assembly, counterweights and any other in-tank components before adjusting for true plane of rotation.

Now that the unit is assembled, it should be in static balance. With the unit in static balance, you can proceed to adjust the machinery to rotate in a true horizontal plane.

Before the drive can be grouted to the center pier or the tank floor can be finish grouted, the scraper arms must be adjusted to revolve in a true plane. Refer to Figure 3. At this time, all rotating machinery, including surface skimmers, counterweights, etc., should have been assembled, any cornersweeps tied back securely and the machinery checked for balance. In the following procedure, you will be working with one arm to establish true plane rotation. After the drive mechanism has been adjusted, the rotating members are merely adjusted for slope parallel to the floor.

Figure 3

.081DR/02-15 1-14

1. Using a transit, establish benchmarks on the tank wall at four (4) compass points at a convenient elevation (Figure 3). If the tank is very large in diameter, establish six

(6) or eight (8) benchmarks; see Table 1.

2. Note the relationship between a point on the top of the arm and the benchmark at compass point 0°.

3. Rotate the arm through 360° and note the above-mentioned relationship at each of the benchmarks. The variations from true plane rotation should all be within the tolerances shown in Table 1.

CAUTION: Do not turn the unit by pushing on the truss arms. Hand turn the worm shaft to avoid damage to the drive. (If Evoqua service personnel are scheduled to assist in the check-out, have temporary power available. The service technician can safely run the drive without the torque overload devices completely installed.)

4. If the variations exceed the tolerance, change the plane of rotation by adjusting the leveling nuts under the drive housing on top of the center pier. Be sure all leveling washers bear against the underside of the drive housing before retightening the top nuts.

5. Recheck variations through full 360° rotation. If they now fall within tolerance, secure the top nuts per the Fastener Installation Instructions. DO NOT grout the drive at this time.

6. If, in making the final adjustment (#4 above), the opposite arm is no longer parallel to the floor elevation, change its slope by adjusting the tie chord "A"-frame clevis between the center cage and truss arm. Use jacks to raise the scraper truss section and adjust the tie chord "A"-frame clevis nut. DO NOT use the turnbuckle on the "A"-frame as a jack.

7. Check that the center cage revolves concentrically with the center pier; make four horizontal measurements, one from the outside surface of the pier to the inside vertical leg of each horizontal angle at the bottom of the center cage. If those measurements are the same within 1/8" (3 mm), torque the center cage drive connection nuts per the Fastener Installation Instructions.

If two of the four measurements differ from the other two by more than 1/8" (3 mm), it will be necessary to add "filler plates" between final drive gear attachment lugs and center cage attaching plates on the side(s) opposite smallest measurements.

.081DR/02-15 1-15

Recheck the measurements after shimming. If they are now within 1/8" (3 mm) of each other, torque fasteners per the Fastener Installation Instructions. The center cage is now concentric with center pier. Do no more shimming at these four joints throughout the balance of erection.

8. Recheck the influent well for level and designed elevation if it is attached to the cage.

After true plane of rotation has been established, grout the drive base. (See Figure 1.) If check-out by an Evoqua service technician is included in your contract, DO NOT grout the drive base until after the installation is checked.

PLANE OF ROTATION TOLERANCE TABLE

TANK NUMBER OF VARIATION FROM

DIAMETER BENCHMARKS TRUE PLANE

UP TO 75' (22.7 M) 4 +/- 1/4"

DIAMETER (6 mm)

76' (23 M) DIAMETER TO 8 + /- 1/2"

119' (36 M) DIAMETER (12 mm)

120' (36.4 M) DIAMETER 8 + /- 3/4"

AND OVER (19 mm)

Table 1

.081DR/02-15 1-16

DRIVE UNIT PROTECTION FOR BLAST CLEANING

If it is necessary to blast clean the equipment in preparation for painting, the drive must be sealed against the entrance of grit. Grit in the drive will cause premature wear. Refer to Figure 4 and take the following steps before blast cleaning.

1. Remove the primary gear reducer, motor, chain, sprockets and chain guard.

2. Apply plumber's putty, followed by two layers of duct tape, at the worm shaft seal of the intermediate reduction unit. Also, protect the shaft itself with two layers of duct tape. This sealing system will stand up under misdirected blasting and is relatively easy to remove.

3. Protect all oil sight glasses, air vent, grease fittings and drive load dial indicator with two layers of duct tape.

4. A felt seal between the stationary housing and the rotating turntable protects the turntable bearing during operation. The felt seal cannot withstand blasting and must be protected with plumber's putty and two layers of duct tape.

5. The upper and lower edges of the dust shield must be sealed with plumber's putty and two layers of duct tape.

After blast cleaning, remove the tape and putty from the shaft, felt seal joint and dust shield. Solvent clean the surfaces which have been puttied before painting the surface.

Duct tape can remain on the other protected areas until painting has been completed.

On some units, a dual drive is furnished to drive both a flocculator and a bottom collector. The primary flocculator drive will be a variable speed unit and should be covered with heavy-duty plastic rather than removed. The steps listed above should be followed with dual drives. There will be two felt seals and two dust shields to protect with plumber's putty and duct tape.

.081DR/02-15 1-17

TYPICAL H-DRIVE

Figure 4

.081DR/02-15 1-18

PREPARING DRIVE UNIT FOR OPERATION

1. Drain the primary reducer oil to proper level per the manufacturer's recommendation in the VENDOR INFORMATION section of this manual.

2. Drain any condensation and site-added oil from the intermediate and final reduction units. Drain plugs are in worm gear drive (upper) housing street elbow and in the final drive (lower) sight gauge tee. See the Drive Assembly Drawings in the manual pocket to facilitate locating all fill and drain plugs. Flush the secondary and final drives with a mixture of 5% Mobil Oil Corp. Mobil System Cleaner and 95% 10W-30 motor oil. Drain and refill to sight gauge levels with seasonably appropriate lubricant. See the MAINTENANCE section of this manual for recommended oils and greases. NOTE: Overfilling of oil will result in oil leaking into the collector.

3. Refer to the Drive Assembly Drawings to locate fittings and regrease all bearings sparingly. Use a low pressure, high volume gun (3 or 4 pumps) to purge all bearings. It is not necessary to regrease electric motor bearings unless they have been stored for more than 6 months - if necessary, regrease sparingly. Use the method and lubricant in accordance with manufacturer's bulletin found in the VENDOR INFORMATION section of this manual to lubricate the electric motor.

CAUTION: After removing the chain from the drive unit, determine the proper rotation once temporary power is available.

4. Microswitches in the worm gear drive (upper) unit can be set now so that the unit can be safely power driven in subsequent erecting procedures. See the "Specification and Torque Overload System" Drawing for settings for your drive.

Refer to the detailed setting instructions in the following pages for making these adjustments.

5. If power is not available, remove the drive chain so the circular drive can be turned by hand in subsequent erecting procedures.

CAUTION: DO NOT TRY TO TURN THE DRIVE BY PUSHING ON

THE TRUSSES--HAND TURN THE WORM SHAFT. If Evoqua Field Service personnel are present, temporary power may be used to rotate the mechanism.

CAUTION: Drive unit should never be operated in reverse rotation. Torque overload protection is not functional and damage could occur to both structure and drive unit.

.081DR/02-15 1-19

TORQUE OVERLOAD MICROSWITCH DEVICE (FIGURE 5)

CAUTION: DO NOT operate the equipment unless the torque overload switches have been checked and electrically connected to the drive. If your contract includes check-out by an Evoqua service technician, do not operate the mechanism until the field check-out is completed.

CAUTION: The torque overload device is only operational when the equipment is operating in the designed direction of rotation. Reversing the mechanism can severely damage the drive unit and/or structure.

CAUTION: DO NOT adjust microswitch gaps at time of overload condition or without first consulting factory.

The torque overload unit is located in a separate housing opposite the driven end of the worm shaft. The device consists of two microswitches 1 mechanically actuated by lineal movement of the worm shaft 2 riding against a spring plate 3.

One microswitch - normally OPEN - should be connected to activate an alarm when a predetermined load is reached. The other microswitch - normally CLOSED - should be connected to shut off the motor if torque loading continues to increase. The torque loadings have been determined for your equipment and related feeler gauge settings for both microswitches are given on the "Specification and Torque Overload System" Drawing. Also refer to the sectional view in Figure 6 for component positions.

A dial indicator 4 is attached to the outside of the microswitch housing. It reads inches of spring plate deflection which relates to torque. It has "ALARM" and "STOP" decals attached to its face. Noting the position of the dial pointer relative to the markings on the decal will give the operator an indication of fluctuations in torque.

TOOLS REQUIRED TO SET MICROSWITCHES

1. Test light

2. Set of feeler gauges

3. Set of Allen wrenches

4. Set of small open end wrenches

Electrical circuits may be energized in the torque overload control box even though the main power has been locked out. Always check for live contacts before making adjustments within the box.

.081DR/02-15 1-20

1. Microswitch 8. Capscrews - Switch Trips

2. Worm 9. Flange Bolts

3. Spring Plate 10. Locknut

4. Dial Indicator 11. Plunger

5. Gap/Switch Pre-Travel 12. Spring Plate Retainer

6. Setscrew 13. Locknut

7. Jam Nut 14. Trip Bar

TYPICAL TORQUE OVERLOAD DEVICE

Figure 5

.081DR/02-15 1-21

ADJUSTING TORQUE OVERLOAD SWITCHES

Figure 6

.081DR/02-15 1-22

PROCEDURE FOR SETTING THE MICROSWITCH GAPS (FIGURES 5 AND 6)

1. Pre-travel in microswitches varies considerably, so it should be understood beforehand that after either switch is properly adjusted, no air gap may exist after the feeler gauge is withdrawn. Because of the pre-travel variation, use of a test light is a necessity, as the click from a microswitch is not always audible.

2. Refer to the drawings and connect the test light to alarm microswitch 1 leads. The test light should be OFF.

3. Refer to the General Arrangement Drawings for proper size feeler gauge for setting the alarm gap 5.

4. Loosen setscrew 6 on top of bar 14; loosen jam nut 7 on the adjusting capscrew and turn the capscrew 8 IN until the feeler gauge will slide easily between the microswitch plunger and the head of the capscrew. Now, turn capscrew 8 OUT (while the feeler gauge is still between the microswitch plunger and capscrew head) until the test light turns ON. While holding capscrew 8, tighten setscrew 6, also tighten jam nut 7 to the bar. Do not overtighten the jam nut as it could upset the adjustment.

5. To check the setting, proceed as follows:

a. Insert a feeler gauge that is .002" (.05 mm) less than the original gauge used;

the test lamp should not light up. Once again, insert the original size feeler gauge and the lamp should light; if not, readjust.

6. Go to Step 1 and repeat the procedure to set the motor shut-off switch. (The test light is ON, but turns OFF when shut-off torque is reached.)

ZEROING THE DIAL INDICATOR (FIGURES 5 AND 6)

The dial indicator 4 may have to be reset to zero several times during installation and initial operation. It should be checked after microswitch adjustment, drive wear in and shortly after the equipment has been rotating in a full tank.

To zero the indicator 4, simply rotate the dial.

.081DR/02-15 1-23

WHEN A TORQUE OVERLOAD CONDITION OCCURS (FIGURES 5 AND 6)

If a torque overload develops that is severe enough to sound an alarm and shut down the drive unit, several steps must be followed to reset the dial indicator and microswitches.

First, use a proper lock-out tag-out procedure to disconnect power to the drive. Reverse the motion of the worm shaft in the drive by either removing the motor fan cover and rotating the fan in reverse or by removing the motor and rotating the coupler in reverse.

Do not use power to reverse the drive. Perform this reverse rotation by hand only.

Continue to rotate in reverse until the surface skimming arm moves backwards several inches and the dial indicator 4 reads zero. Care must be taken when moving the skimming assembly backward. If it is near the scum trough and beach, lift the skimmer over the trough if interference occurs.

After the mechanism has been reversed and the dial indicator reads zero, the load on the spring plate will be released and the microswitches should return to their normal positions. Power can be reconnected to the drive and the unit should be run forward under normal power. If the overloads trip again or if the unit cannot be manually reversed, it will be necessary to look for the cause.

There are numerous causes for drive overloads. The most common are high sludge loading or skimmer problems. Skimmers can hang up on the trough/ramp due to loosening of mounting hardware, misalignment or ice build-up on the trough or ramp.

Other less common causes are from the mechanism jamming against pressure relief valves in the floor or walls of the tank. Loosened floor grout can jam the mechanism. In cold weather, the freezing of accumulated condensate in the unit's oil reservoir can jam the lower drive unit. If no cause for the overload can be determined, call Evoqua's Water Technologies Field Service Department for assistance.

If, after identifying and correcting the cause of the overload, the dial indicator would not return to zero, the spring plate 3 may be damaged. DO NOT adjust the microswitch gaps without first inspecting the spring plate.

.081DR/02-15 1-24

DISASSEMBLY AND SPRING PLATE INSPECTION (FIGURES 5 AND 6)

Remove flange bolts 9 and carefully withdraw the unit. The unit can now be further disassembled using the following steps.

1. Remove the dial indicator 4 from the housing.

2. Loosen nut 10 on adjustable plunger 11 and remove plunger from the spring plate retainer 12.

3. Spring plate retainer and spring plate 3 can now be removed from the housing.

4. Remove spring plate retainer 12 and locking nut 13 and disassemble the spring plate from the spring plate retainer.

5. Check the spring plate for flatness; if deformed, replace it.

REASSEMBLY

Reverse the preceding procedure to reassemble. One test must be made before resetting the microswitches. This test is to be made with the drive under no load. When all but the dial indicator have been reassembled and installed, observe the dial needle. It should move at least a quarter turn as the indicator is being tightened down. If the needle does not move off the peg, loosen the nut on the adjustable plunger and screw the plunger out of the plate retainer until it moves the pointer one quarter revolution. Hold the plunger while retightening the locking nut against the bar. The air gaps should now be reset as previously outlined.

OVERLOAD HOUSING DRAIN PLUG

The overload housing is equipped with a vent at the bottom. The vent allows condensation to drain from the housing to prevent corrosion.

NOTE: If the drive unit is explosion proof, no vent is provided; the unit continuously drains through conduit access holes.

.081DR/02-15 1-25

TORQUE OVERLOAD DEVICE

The unit is equipped with a shear pin sprocket. The shear pin number will be identified on the Drive Assembly Drawing or the List of Materials. The shear pin number will include a dash number and a series letter, e.g. CA1943-22E, CA680-1A, etc. The last number and letter is marked on the end of the pin (Figure 7). Examine the shear pin end and compare the dash number and letter with the drawing. If a discrepancy occurs, contact the factory representative or the factory at once. Under NO circumstances should a shear pin of different value be substituted. Failure to comply with this could severely damage the equipment and void any factory warranty. Grease the sprocket bore and shear pin faces before operating the drive under load. Any major brand of Lithium based #2 may be used.

Figure 7

.081DR/02-15 1-26

PRE-OPERATIVE CHECK

CAUTION: Even if running under temporary power, do not bypass the overload devices of the unit.

If power is available, we suggest operating the unit in a dry tank for at least two complete revolutions, or if possible, for a period of four hours, then check to see if the arm(s) are still operating on the same plane.

Lightly grease the flexible seal contact surfaces during dry tank operation.

During the dry tank run-in, check out the unit for the following:

1. Smooth operation - no stopping or jerking movement.

2. Overheating - the temperature of the reducer should not be uncomfortable to the hand. Motors must be protected by proper heaters in the starter.

3. Oil leaks through reducer seals or drain plugs.

4. Oil leaks through main drive unit drain plugs or level gauges.

5. Action of the surface skimmer as it traverses the scum beach.

TORQUE TESTING PROCEDURE

If a torque test is required per the contract documents, a Evoqua service technician will perform the following recommended torque test procedure.

Verify the circular equipment to be tested has been inspected for proper installation and the tank floor is free of debris. The overload switches MUST be wired into the alarm/shut-off circuit as required by the General arrangement drawings. With permanent power connected, operate the drive under power for a minimum of one full rotation and check for free and quiet operation of drive and structural components.

Inspect the torque test kit and verify all items are accounted for and undamaged.

.081DR/02-15 1-27

Locate the attachment points on the truss per the dimensions indicated on the Torque Test General Arrangement Drawing. At those points, attach a polyester strap to the trailing bottom chords of both truss arms. Connect a hydraulic cylinder to the other end of each strap. NOTE: The hydraulic cylinder should be in the fully retracted position. Locate each cylinder back away from the truss so the strap/cylinder is 90 degrees to the centerline of the truss. Mark and install anchors for the cylinder mounting brackets into the floor or the wall as required. The location of the attachment points and mounting of cylinders is very important and must coincide with the Torque Test General Arrangement Drawing.

Connect the hydraulic hose to the rod end port of the cylinder and the common tee/gauge assembly. Repeat the procedure with the other cylinder. Locate the pressure gauge assembly up on the bridge near the drive unit. Fill the cylinders and hose assemblies with hydraulic fluid at the gauge assembly, allowing trapped air to escape. Wire in the start/stop toggle switch into the motor circuit (NOTE: Lock out electrical power when connecting toggle switch).

The following procedure is required before the actual testing to properly set the spring plate into the overload housing. Start the drive and with the use of the start/stop toggle switch, gradually increase the torque, as indicated by the pressure gauge assembly, to operating pressure. Stop the drive and reverse the motor leads (NOTE: Lock out electrical power when reversing motor leads) to remove all load from the cylinders and truss arms.

TORQUE OVERLOAD CONTROL BOX

Electrical circuits are energized in the torque overload control box.

Always check for live contacts before making adjustments within the box.

At this point, check and adjust, if required, the microswitch gaps per the Specification General Arrangement Drawing. Zero the torque/deflection dial indicator. Remove shear pin and verify it matches the size indicated on the Specification General Arrangement Drawing. Verify the shear pin hub is free to rotate before reinstalling the shear pin.

.081DR/02-15 1-28

The torque test is now ready to be performed. Start the drive, and with the use of the start/stop toggle switch, gradually increase torque and pressure in the hydraulic cylinders.

When the pressure gauge indicates a test point has been reached, verify the protective action, alarm sounding or motor shut-off has occurred. If not, adjust the designated microswitch setting to actuate at that point. Continue testing until the last test point has been reached.

The drive motor rotation should be reversed to remove the truss arm loading. Lock out electrical power when reversing motor leads. Be careful that the cylinder rod is retracted during the reversal to prevent any damage. NOTE: Drive overload protection is not functional when operating in reverse from normal rotation.

The Evoqua service technician may repeat the test to verify the overload settings by reversing the drive to remove loading to the mechanism and restarting the test as described above.

Reverse the drive to remove loading to the mechanism before disassembling the torque test kit equipment.

After testing is completed, check that the motor is wired for proper rotation as indicated on the General Arrangement Drawings.

Remove or grind off the anchors that were holding the cylinder mounting brackets. This area must be smooth and not cause interference with rotating equipment.

OPERATION

.081DR/02-15 2-0

SECTION 2 CONTENTS

ITEM PAGE

SAFETY PRECAUTIONS 2-1

START-UP 2-2

TANK FILL-UP 2-3

WINTER OPERATION 2-3

SHUT-DOWN 2-4

EMERGENCY OPERATING SHUT-DOWN PROCEDURES 2-4

.081DR/02-15 2-1

CIRCULAR “H” DRIVE UNIT REPLACEMENT

SAFETY PRECAUTIONS

The primary hazards associated with operating circular collectors are identified below.

OPERATING ENVIRONMENT

Circular collectors are usually exposed to the elements. The bridge and other access points may become slippery when wet or icy.

Handrails and other safeguards must be in place when operating the equipment. Use care when access is necessary. Stay within handrails at all times.

GUARDS

Guards cover several points on circular collectors to prevent personal injury from moving parts. Guards must be in place when operating the unit.

.081DR/02-15 2-2

TORQUE OVERLOAD CONTROL BOX

Electrical circuits may be energized in the torque overload control box even though the main power has been locked out. Always check for live contacts before making adjustments within the box.

START-UP

If the unit has been sitting idle for some time, either before initial start-up or after a winter shut-down, the following should be checked before filling the tank.

1. When tank is equipped with pressure relief plugs or valves in the floor, be sure these are closed.

2. Check the position of valves that control the hydraulics of the unit.

3. Check the position of the weirs. On initial start-up, they should be set at maximum height so that after the tank is filled, they can be evenly adjusted to the design bottom of V-notch weir elevation. Tighten down the weir bolts after making this adjustment.

4. Check oil level in the reducers, note its condition and drain and refill if necessary.

Be sure it is the correct viscosity for anticipated ambient temperatures in which the reducers will operate. Grease all fittings.

5. Be sure the dial indicator is set at zero, then start the unit.

NOTE: If your unit is equipped with an "LVDT", Linear Voltage Differential

Transmitter, be sure that the meter is zeroed out at this time.

CAUTION: When raw sewage is flowing or present in tank, operation of the unit should not be stopped for a long period of time without first draining the tank. This especially holds true when there is a large percentage of solids in the flow. A dense build-up of sludge on the tank floor can overload the drive, making it impossible to start up the unit.

.081DR/02-15 2-3

TANK FILL-UP

When the tank is full, note and record the dial indicator reading. A normal pattern of readings should be established so that an overload condition can be anticipated and corrected.

WINTER OPERATION

Normally, the unit should operate the same during the winter as it does in other seasons.

When ambient temperature falls below freezing, it is necessary that sewage flow to the unit is continuous.

When the weather becomes extremely cold, particular attention should be given to the scum beach and all skimming equipment. Torque overload devices are rated and set for the loading requirements of the submerged rotating equipment. Skimmer construction is based on lighter load requirements and can be damaged without activating the torque overload device.

CAUTION: The skimming equipment might be damaged from a build-up of frost, ice or snow. Temporarily remove the skimming equipment or tie it up so that it will clear any possible build-up.

It is imperative that all ice has melted from the tank before a start-up. The tank should be probed in as many areas as possible to determine whether any ice is present under the melted surface water. If it is possible to draw the tank down before start-up, break up all ice beforehand and then drain. Hose down the equipment in the tank and the tank itself Examine the equipment for any ice damage. Repair or replace any damaged equipment.

Check the tank floor for surface irregularities which might have occurred due to heaving.

NOTE: EVOQUA ASSUMES NO RESPONSIBILIT'Y FOR DAMAGE TO

EQUIPMENT WHICH IS SUBJECT TO WEATHER CONDITIONS THAT

MAY REQUIRE THE PROCEDURES SUGGESTED ABOVE. ONLY THE

PLANT OPERATORS ARE IN A POSITION TO DETERMINE THE

DEGREE OF EQUIPMENT PROTECTION REQUIRED. DAMAGE TO

THE STRUCTURAL MEMBERS CAN RESULT IF ICE IS PRESENT AND

THE TANK IS EMPTIED, PERMITTING ICE TO FALL OR LAY ON

ROTATING MEMBERS OR ON THE TANK FLOOR.

.081DR/02-15 2-4

EVOQUA DOES NOT RECOMMEND the use of fuel conditioning products such as "Diesel Heat" to thin or modify the gear oil in Evoqua circular drives during extremely cold weather. This product sufficiently dilutes the oil (lowers viscosity) and inhibits the ability of the oil to maintain an oil film between moving parts. The gearing and ball bearings operate so slowly that a true hydrodynamic film cannot be developed and thus the thinned oil is literally "crushed" under the contact areas. When this occurs, the oil actually reaches its flash point and ceases to lubricate.

Also, it is not recommended flushing bull gears with oil during operation. The reasons for not doing it are the same as in the previous paragraph. Flushing with oil while the unit is shut down is approved.

SHUT-DOWN

When a shut-down is expected, the following procedure is recommended.

1. Drain the tank down, then turn off and lock out the drive.

2. Hose down the tank and all submerged equipment.

3. Inspect the submerged equipment for any damaged or missing parts. Fix and replace as needed.

4. Fill all reducers with the proper type lubricant, close vents and grease all fittings on the drives. Remove the motor and store it in a warm, dry place. Cover the reducer "C"-faced motor mount with a tarp. The motor and all reducer shafts should be rotated by hand 1-1/3 turns every 60 days.

5. If the tank floor is equipped with pressure relief plugs or valves, open them and also open the tank drain. If the tank is not so equipped, it will have to be sufficiently filled with water to prevent it from heaving. When prolonged freezing weather is expected during a shut-down, the tank should have continuous flow.

CAUTION: When raw sewage is flowing or present in tank, operation of the unit should not be stopped for a long period of time without first draining the tank. This especially holds true when there is a large percentage of solids in the flow.

A dense build-up of sludge on the tank floor can overload the drive, making it impossible to start up the unit.

EMERGENCY OPERATING SHUT-DOWN PROCEDURES

If the equipment malfunctions, it cannot be permitted to continue to run. Follow the sequence of operation of the controls for the equipment and turn off and lock out the drive(s). Follow the Lock-Out procedures shown under the Safety Precautions in the MAINTENANCE section of this manual. Determine the reason for the malfunction and take corrective action. If a shut-down period is required to repair the situation, follow the plant procedures for taking the equipment off line.

MAINTENANCE

.081DR/02-15 3-0

SECTION 3 CONTENTS

ITEM PAGE

SAFETY PRECAUTIONS 3-1

H-DRIVE 3-4

GENERAL PRECAUTIONS 3-5

RECOMMENDED…