How to Rebuild an Oversized Keyway

 In Belzona Educates, How To Series

introduction to oversized keyways

Oversized keyway is a common problem when it comes to the functionality of rotating equipment. Small components always lead to large problems. Keys in shafts have to withstand the stress of sudden starts and stops. Whether it wears or breaks, the entire unit is shut down. In many plants, the costly and time-consuming process of replacing the key still involves disassembly of the machine, removal of the shaft and the machining of a new key and keyway. While this process has significant costs, it is usually only a fraction of the cost of the unit being out of service until it is complete. Maintenance management tired of the inconvenience and the expense of traditional methods have adopted Belzona solutions. By using a Belzona metallic polymer, a damaged keyway can be rebuilt in situ, eliminating the need for time-consuming and costly disassembly. Since Belzona polymers are 100% solids, there is no dimensional change from application to full cure. This means that the key can be used to construct a new keyway with a perfect fit.

want to know how to repair metal with cold bonding?

Click here to learn.

Belzona How-To

In this blog post, we demonstrate how to repair an oversized keyway with Belzona 1111 (Super Metal), an epoxy based metal repair composite. You will learn how to carry out a keyway repair in situ, without the need to disassemble the equipment or take the shaft out of service. Belzona metal repair composites eliminate the need for welding or any other type of hot work, thus providing a safe environment for personnel.

Drawing: Oversized Keyway Repair

Oversized keyway repair drawing

To carry out an oversized keyway repair, we used Belzona 1111 (Super Metal), a new key, Belzona 9111 (Cleaner/Degreaser), Belzona 9411 (Release Agent) and a few tools from our machine shop. First, we had to condition the key with Belzona 9411. Then, we filed down the internal surface of the keyway to remove all sharp edges and protrusions, and roughened the surface to achieve maximum adhesion with the epoxy product. The surface was cleaned with Belzona 9111 to remove all the contaminants. Next, Belzona 1111 was thoroughly mixed and applied to the internal surface of the keyway until the keyway was filled with the mixed product. The key was carefully positioned on top of the applied product and pressed down firmly to allow the excess product to exude. Once the product fully cured, the key was removed from the keyway.

Video: How to Repair Oversized Keyway with Belzona

SUPPLIES AND TOOLS NEEDED FOR AN OVERSIZED KEYWAY REPAIR WITH BELZONA 1111

Step-by-step instructions of oversized keyway repair with Belzona

timeline_pre_loader
SURFACE PREPARATION

CONDITION KEY

Oversized Keyway Repair

Condition all sides of the key with Belzona 9411 (Release Agent).

PREPARE SURFACE OF KEYWAY

Oversized Keyway repair

Step 2: Prepare the surface using a file to remove sharp edges and protrusions.

Prepare the surface using a file to remove sharp edges and protrusions.

SCORE KEYWAY

Oversized Keyway repair

Step 3: Roughen and score the inside of the keyway.

CLEAN REPAIR AREA

Oversized Keyway repair

Step 4: Clean and degrease the keyway to remove all surface contaminants.

TAPE REPAIR AREA

Oversized keyway repair

Tape the repair area.

PRODUCT APPLICATION

Mix Belzona 1111

Oversized keyway repair

Mix Belzona 1111 until a uniform color, free of any streakiness, is achieved.

APPLY MATERIAL INTO KEYWAY

Oversized keyway repair

Apply the mixed material directly onto the prepared surface of the keyway, pressing down firmly to ensure maximum contact with the surface.

FILL IN KEYWAY

Oversized keyway repair

Fill in the keyway with the mixed product.

REMOVE EXCESS

Oversized keyway repair

Remove excess product.

POSITION KEY

Oversized keyway repair

Position the key over the applied product and press down firmly to allow the excess product to exude.

REMOVE TAPE

Oversized keyway repair

Remove tape.

RELEASE KEY

Oversized keyway repair

Release key.

SMOOTH OUT

Oversized keyway repair

Smooth out the surface with an emery cloth.

Want more information?

Visit our website: www.belzona.com/metal-repair

Comments
    pingbacks / trackbacks

    Leave a Comment

    Start typing and press Enter to search

    Pin It on Pinterest

    Share This