National Flooring Equipment 3397, Service Manual

Maintenance

10

Fitting the Chain (Figure 3)

Before mounting the chain, it must be degreased.
The chain is supplied as a chain string and must be prepared during mounting. This is 

done as follows: 

1.  Place chain on the sprocket so that the links lie in adjacent gaps between the teeth. 
2.  Close chain using a master link. With heavy chains or longer distance between the 

shafts, use a pre-stressing tool to bring the two end links closer together so that the 

master link can be inserted without being deformed. 

Note: 

Chain links with springs should have their closed sides pointing in the running 

direction (L) of the chain (S). Slide in the link adapter (V); place the link plate opposite of 

the spring and press it over the pin into the ring groove using a pair of tongs. Demount 

the spring in the reverse order. 

Maintenance and Repairs

A chain drive needs little maintenance if the correct chain has been selected, mounted 

correctly for the application, and is not lubricated with grease. A chain guard protects the 

drive chain. The chain guard prevents excessive contamination and accidents.  
The drive must be cleaned every three months; on these occasions, check the alignment 

of the chain sprockets and tension. 
In order to clean thoroughly:

• 

Remove the dirt on the outside of the chain drive using a hard or wire brush. 

• 

Wash the chain in mineral spirits or other solvent. 

• 

Clean the dirt from the internal parts of the chain by putting the chain in mineral 

spirits or other solvent for approx. 24 hours. Move the chain several times back and 

forth while in the solvent to clean the joints. 

REPLACING THE WHEEL KIT

The wheel kit consists of the blast wheel, control cage, lock washer, and retaining bolt. 

Demounting (Figure 4)

1.  Remove the feed spout (A) by pulling it out of the control cage.
2.  Loosen the cage clamps (B) and remove the control cage (Z).
3.  Unscrew the four acorn nuts of the front cover plate (F); remove the plate.
4.  Unscrew the retaining bolt (H) of the blast wheel (R) while holding the blast wheel 

still. Take the blast wheel out of the housing.

5.  Check the wheel adapter (D) for wear and replace if necessary.

Mounting (Figure 5)

1.  Clean all threads and use a new blast wheel retaining bolt. Place blast wheel (R) 

on the wheel hub (D) through the blast housing opening so the wheel fits with the 

adapter pins (M). Tighten the blast wheel by the retaining bolt(H).

2.  Re-attach the front cover plate (F) using the four washers and acorn nuts.
3.  Insert the control cage (Z) in the center and clamp the control cage with the cage 

clamps (B) so that the blast wheel can rotate free with an overall clearance of 1/8” 

(3 mm) to the impeller. The blast wheel must rotate freely.

4.  Preset the notches or guide lines, on the face of the control cage, to the 9:00 and 

11:00 positions (OK and UK respectively) as shown in Figure 5.

FIG. 3

FIG. 4

FIG. 5