Repair

1) General

A roller chain drive, like any other mechanical operating equipment, requires maintenance attention to obtain satisfactory performance and long service life.

[LOCK-OUT REQUIRED.]

Chain Tension (NEVER TOUCH A MOVING CHAIN OR SPROCKET.)
(Drive assemblies and boom assemblies)
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2) Motor Drive Chain Adjustments (LOCK OUT UNIT)

Each drive motor unit has its own device for maintaining proper chain tension. Adjustments can easily be made. Loosen the gear box mounting bolts and tension drive chain by moving the position of the gear box. This is accomplished by adjustment of the pusher bolts attached to the motor mounting plate.

The amount of sag should be determined from the table below.

SAG FOR VARIOUS CENTER DISTANCE

3) Boom Chain Adjustment

a. General

The conveyor’s booms are moved by means of chain anchors which fasten one boom to the next. This creates a locking position causing rotation to be given to the chains for each boom. Each boom moves in proportional motion so that all are extending the same amount. The booms are driven through chains attached to a master drive shaft located in the main or fixed section of the conveyor. The chain on each boom is attached to the mounting anchors with master attachment links which can be observed and serviced by means of access panels on the side of the boom sections of the conveyor or through the conveyor.

Each section of the boom driving chain has an individual take-up sprocket which can be adjusted either from the access panels on the side of the conveyor or on the forward end of the booms as the boom is moved slightly forward exposing the take-up sprockets. NEVER REACH UNDER THE CONVEYOR WHEN THE BELT IS RUNNING. The idler sprockets are mounted upon “Oilite” bearings and need not to be lubricated. Adjustment of the take-up sprocket is by means of a screw and jam nut pushing a mounting plate in the suitable slide.

b. Adjustment Procedures

Because the extendable conveyor uses the dual chain design, it is very important that the chains on each side of the conveyor be equally tensioned. If one chain is allowed to drive the conveyor, various problems may arise, such as belt tracking, boom alignment and chain breakage.

Each boom (except the first boom) has a front and a rear chain tension device. The side the slackness of the chain is in (top or bottom) determines which take-up assembly is to be adjusted.

The following is a general guide for tensioning the boom chains. The following is for a triple boom unit. Other units are similar if followed from the rear of the fixed section to the first boom.

Fixed Section Adjustments: (LOCK OUT UNIT)

1. Adjust rear sprockets if chain slack is on top side of sprocket extending to the rear third boom anchor.
2. If slackness is on the bottom side of the rear sprocket or on top side of the fixed section, the front sprocket adjustment should be made using the fixed section front sprocket.

Third Boom Adjustment:

1. Adjust the rear sprocket if the slackness is on the top side of the rear sprocket between the sprocket and the rear second boom chain anchor. Also adjust the rear sprocket if the slackness is between the bottom side of the rear sprocket and the fixed section front anchor.
2. Adjust the front sprocket if the slackness is on the top side of the front third boom idler sprocket between the sprocket and the rear second boom chain anchor. Also adjust the front sprocket if the slackness is between the bottom side of the front sprocket and the fixed section of the front anchor.

Second Boom Adjustment:

1. Adjust the rear sprocket if the slackness is on the top side of the rear sprocket, between the sprocket and the rear boom chain anchor. Adjust the rear sprocket also if the slackness is between the bottom side of the rear sprocket and the third boom front chain anchor.
2. Adjustment to the second boom front sprocket is made if the slackness is between the bottom side of the rear sprocket and the third boom front chain anchor.

The procedure may appear to be a bit confusing; therefore, it is recommended that before an adjustment is made along with the chain path drawing for clarification.

If at all possible, these adjustments should be made with the conveyor extended. When adjusting the chain, do not over tension to the point that turning of the sprocket adjustment screw will move the entire boom.

Always tension the chains equally on both sides of each boom. This will distribute the driving forces equally.

The recommended amount of torque pressure that should be applied to the take-up adjustment bolt is in the range of 110 to 130 inch/pounds of torque. We recommend the proper torque wrench be used when setting the take-up. When adjustment is complete, reposition and tighten the jam nut on the take-up slide.

Finally, always replace any guards or covers that may have been removed for performing of these adjustments.

Electrical Cable Reel

Inspect the electrical cable to ensure that the cable is not pulling out from a cable connector. Also, completely extend and retract the conveyor, observing the recoil of the cable. If the cable is sagging, completely extend the conveyor and attempt to add an additional wrap to the spring at the reel housing. (Do NOT over tension the spring by over wrapping the cable.) See manufacturer’s literature.

The cable should be cleaned each month with a de-greaser or general purpose solvent. This will remove any dirt and paper dust that attaches to the cable and becomes sticky. Without removal of this buildup the cable will recoil on one side of the spool and have a higher tendency to come out of the re-spooling area.

Once the cable has come out of this area it will normally break the cable in half and stop the conveyor operation. Once the cable is clean, a powder or silicone spray may be added to the jacket of the cable to help insure it re-spools properly across the entire spool area and not on one side only. This cleaning operation should take place with the conveyor completely extended the power LOCKED OFF.

To add extra tension to the reel spring, completely extend the conveyor and pull the control cable out by hand, making one rotation to insure the spring can accept the added tension. If this hand tension causes the spring to bottom out and will not allow the cable to be extended, the spring has reached maximum tension and must be replaced. If added tension can be placed on the spring, completely retract the conveyor and LOCK POWER OFF.

Pull the cable out by hand while holding the reel spool with the opposite hand. Wrap the cable around the spool one rotation to add an extra loop of spring pressure to the reel system. Extend and retract the conveyor to insure that the cable is now properly recoiling. If not, repeat the procedure until the proper operation is achieved.