What Should Be Checked Before a Packed Tower Is Closed After Internal Installation?

Once tower internals have been installed, there is often pressure to close the vessel and restart production quickly.

This is the worst time to skip inspection.

After the tower is closed and filled with process liquid, correcting a small installation mistake can require another shutdown.

A final internal inspection should therefore be completed before vessel closure.

Start with Foreign Material Removal

Check for:

• tools;
• welding rods;
• plastic film;
• loose bolts;
• packaging material;
• debris.

Foreign objects can:

• block distributor holes;
• damage packing;
• obstruct drains.

Housekeeping is an engineering issue inside process equipment.

Verify Packing Support

Before final closure, confirm that the support:

• is correctly seated;
• is securely connected;
• has no obvious deformation;
• remains unobstructed.

If packing has already been loaded, direct inspection may be limited, making earlier stage inspection important.

Check Packing Bed Condition

For random packing, verify:

• correct bed height;
• reasonably level top surface;
• no obvious large voids;
• no excessive breakage.

For structured packing, confirm:

• layer orientation;
• segment positioning;
• correct total height.

Verify Hold-Down or Bed-Limiter Installation

If required, make sure the top grid:

• is correctly positioned;
• does not excessively compress the bed;
• is secured as designed.

Inspect the Liquid Distributor

This is one of the most important pre-closure checks.

Confirm:

• levelness;
• correct orientation;
• clean outlet holes;
• feed connections;
• secure supports.

A blocked distributor can make the entire packed bed ineffective.

Water Testing May Be Useful

Where practical, a water-distribution check can identify:

• blocked outlets;
• gross maldistribution;
• leaks.

This does not replace full hydraulic engineering, but it can identify installation errors.

Check Demister Assembly

Verify:

• all sections are installed;
• perimeter sealing is complete;
• section joints are closed;
• support is secure;
• drainage is unobstructed.

Even a small gap may allow gas bypass.

Confirm Fasteners

Check that:

• required bolts are present;
• connections are secure;
• temporary fasteners have been removed.

Material should match the approved design.

Verify Clearance Around Nozzles and Instruments

Internals should not interfere with:

• level instruments;
• spray nozzles;
• pressure connections;
• drain lines.

A part installed slightly out of position can block an instrument connection.

Take Photographs

Photos before closure create a valuable permanent record of:

• packing condition;
• distributor arrangement;
• demister installation;
• component orientation.

These images may be extremely useful during future troubleshooting.

Use a Signed Punch List

Any incomplete issue should be recorded.

The vessel should not be closed simply because the installation team is ready to leave.

Items should be classified as:

• acceptable;
• corrected;
• still open.

Final Engineering Principle

The final inspection is the last opportunity to verify tower internals at very low cost.

After startup, every hidden error becomes more expensive.