A packing plate, also known as a filler plate, in a steel structure is a piece of steel used to fill gaps between structural connections, typically in bolted connections. It ensures proper alignment and load transfer.
Purpose and Use of Packing Plates
Packing plates serve several critical functions in steel construction:
- Gap Filling: Primarily, they fill gaps that arise due to manufacturing tolerances, design discrepancies, or erection inaccuracies. This is vital for maintaining the integrity of the structural connection.
- Alignment: They are crucial for aligning steel columns, ensuring they are vertically plumb and at the correct elevation. This is often seen during the erection phase of a steel structure.
- Load Transfer: Packing plates facilitate the even distribution of load across the connection, preventing stress concentrations and ensuring structural stability.
- Shimming: They can act as shims to fine-tune the fit between connected members.
Common Applications
- Column Alignment: During column erection, packing plates are frequently used at the base to ensure proper vertical alignment and level.
- Beam-to-Column Connections: When connecting beams to columns, packing plates can compensate for slight variations in dimensions, ensuring a snug fit.
- Base Plates: Used under base plates of steel columns resting on concrete foundations to achieve the desired elevation or level the column.
Advantages of Using Packing Plates
- Simplified Erection: They make it easier to erect steel structures by compensating for minor imperfections.
- Cost-Effective: Often cheaper than modifying structural members to achieve a perfect fit.
- Flexibility: Provide flexibility in adjusting connections during construction.
Considerations
- Material: Typically made from steel compatible with the connected members.
- Thickness: The thickness is chosen to precisely fill the gap.
- Proper Installation: Requires careful installation to ensure proper load transfer and prevent loosening.
- Corrosion Protection: Should be treated with appropriate coatings to prevent corrosion.
In summary, a packing plate is an essential component in steel construction, used to fill gaps, align members, and ensure effective load transfer in structural connections, contributing to the overall stability and integrity of the structure.
