Corrugator Double Facer Heating: Controlling Heat for Flat, Bonded Board

The double facer is where the outer liner bonds to the flutes, and the heat applied there decides whether the board comes out flat or warped, bonded or delaminated. Controlling heating — steam temperature, hot plate contact, and dwell — keeps the adhesive gelling evenly so the board is flat and the bond holds, avoiding the warp and delamination that scrap a run.

The Scenario: Heat that must bond evenly

Double facer heating faces three challenges:

Pain Points

• Uneven heat across the web causes warp and delamination in the finished board;
• Insufficient heat leaves adhesive under-gelled, producing weak, delaminating board;
• Excess heat can scorch the liner or dry the adhesive before it bonds.

The Solution: Three heating-control solutions

Three controls deliver flat, bonded board:

1. Steam temperature control Precise steam temperature control keeps heat even across the web.

2. Hot plate contact and dwell Correct hot plate contact and dwell let the adhesive gel evenly.

3. Bond monitoring Monitoring bond quality catches under-gelled or scorched board before it ships.

The Result: Flat, bonded board every run

With heating controlled, the double facer produces flat, well-bonded board, cutting warp and delamination.

Sources & Evidence

• The double facer bonds the single-faced web to the second liner under heat and pressure to form double-wall board. (Source: FEFCO / corrugator machinery references)
• Starch-based adhesives are the dominant bonding agent in corrugated board, typically derived from corn or wheat starch. (Source: TAPPI technical references — corrugated adhesives)