Case Erector Jams: Why the Case Packer Runs Out of Cases

Key takeaways

• Blank quality and blank handling cause most erector jams.
• Give blank quality its own code, or supplier problems land on the crew.
• An erector stop only reaches the case packer when it outlasts the case buffer.
• Tape and glue running out are material stops, not machine faults.
• Many erector minutes can turn into few filler minutes, so price stops by what reached the filler.

Case erector jams usually start with the blank: warped, damp or badly scored blanks, double picks and misfeeds, then problems at folding and bottom sealing. When the erector stops long enough to empty the conveyor of erected cases, the case packer runs out of cases, and if that lasts, the filler is blocked.

Fabrico, an OEE and light MES platform, logs each stop on the erector and the case packer and keeps own stops apart from starved and blocked time, so an erector jam is not booked as a case packer problem. This guide covers where erectors stop, how a jam travels down the line, how to code it, and what to fix first.

What does a case erector do, and where does it stop?

A case erector takes a flat corrugated blank, opens it into a case, folds the bottom flaps and seals them with tape or hot melt glue. The erected case then travels to the case packer. Each step has its own stops.

Why are blanks the biggest cause of erector jams?

A case erector is built to handle a blank that is flat, dry, square and well scored. Real blanks are not always like that:

• Warped blanks from storage in damp or changing conditions misfeed and do not open cleanly.
• Poor scoring makes flaps fold in the wrong place or spring back.
• Blanks stuck together cause double picks.
• The wrong blank loaded after a format change jams at once.

These look like machine faults on the screen, but they trace back to storage, to the supplier or to the changeover routine. Our case packer OEE guide makes the same point for the packer's own blank magazine.

How does an erector jam travel down the line?

There are usually two buffers between the erector and the filler:

1. The case buffer: erected cases waiting on the conveyor to the case packer.
2. The product buffer: bottles or packs waiting in front of the case packer, which protects the filler.

An erector stop first drains the case buffer. Only then is the case packer starved of cases. The packer's stop then fills the product buffer, and only when that is full is the filler blocked. A short erector jam often never reaches the filler at all. Our guide to starvation and blocking explains how to read these states.

How should case erector stops be coded?

• Blank quality: warped, damp or badly scored blanks. Material group, with the supplier and lot in the note.
• Magazine empty: material or crew, depending on who refills it.
• Double or missed pick: short stop at the pick.
• Fold jam: short stop or settings, depending on the cause.
• Tape out or glue empty: material group.
• Glue skip or nozzle clog: glue system.
• Format change: changeover, with a standard time per format.
• Blocked by case packer: charged to the packer.

Keep the list short and in the operators' words. Our guide to operator friendly reason codes shows how.

What does one shift of erector jams cost?

Sample line (illustrative numbers, not a customer): a filler at 240 bottles a minute, packed 12 to a case, so the case packer and the erector both run 20 cases a minute. The conveyor holds 30 erected cases, or 1.5 minutes. The product buffer in front of the case packer holds 2 minutes. One shift:

• Double picks and warped blank jams do not outlast the 1.5 minute case buffer, so the packer never runs out of cases.
• Each tape out starves the packer for 6 minus 1.5 = 4.5 minutes, and blocks the filler for 4.5 minus 2 = 2.5 minutes. Two of them: 9 packer minutes, 5 filler minutes.
• Each empty magazine starves the packer for 3 minus 1.5 = 1.5 minutes, which ends inside the 2 minute product buffer.
• So 57 erector minutes became 15 case packer minutes and only 5 filler minutes: 5 x 240 = 1,200 bottles not filled.

The two tape outs, a reorder problem, are the only stops that cost output this shift. The 30 double picks still matter: they keep an operator busy all shift, and they are a sign of blank or vacuum problems that can get worse.

Which fixes reduce case erector jams?

• Blank storage: dry, stable conditions, first in first out, and blanks brought to the line shortly before use.
• A blank quality code and a short supplier spec, so repeat problems reach the buyer with data.
• Vacuum cups and pick settings checked and cleaned on a schedule.
• Centerlines per format for guides, folding and the magazine.
• Reorder points for tape and glue at the line, and a level check at each shift start.
• A case buffer sized to cover the usual short erector stops.

Short erector stops add up in the same way as micro stops anywhere else on the line. Our article on micro stops on packing lines shows how.

Where Fabrico fits

Fabrico is a computer vision enabled Manufacturing Performance Platform. OEE and light MES come first, with computer vision on stops.

• Automatic downtime logging on the erector and the case packer, with own, starved and blocked time kept apart.
• The operator confirms the reason in one tap, so a warped blank and a double pick get different codes.
• A camera clip as evidence for a stop, where a camera watches the magazine or the pick.
• Every loss priced in money and ranked, so only the stops that reached the filler carry a line cost.

You start with a pilot on one line, with a baseline and a decision date agreed in advance. There is no free plan and there are no tiers: each plant gets a quote. Read how a light MES starts on one line in our light MES guide.

Frequently asked questions

What causes case erector jams?

Most often the blanks: warped, damp, badly scored or stuck together. Then pick problems such as worn vacuum cups, folding settings, and tape or glue running out.

Does a case erector jam stop the filler?

Only if it lasts longer than the buffer of erected cases plus the product buffer in front of the case packer. Short jams usually do not.

Should blank problems be coded as machine faults?

No. Code them as blank quality in the material group, with the supplier and lot, so the problem reaches the people who can fix it.

How big should the case buffer be?

Big enough to cover the erector's usual short stops at the case packer's speed. Measure your stop lengths and compare.

Is tape out a breakdown?

No. It is a material stop. A reorder point and a level check at shift start usually remove it.

See your end of line in a demo

Bring one line and its current stop log. We will show the erector's stops and what reached the filler.

Request a demo · Contact us