Vietnam Mattress Foam Plant Cuts Sheet Tolerance to 0.05 mm with a C717 Slicer

Dong Nai, Vietnam — A mattress foam converter supplying three local mattress brands has rebuilt its sheet cutting line around a C717 long size foam horizontal slicer. The plant cut thickness variation from roughly ±0.15 mm to within ±0.05 mm on thin layers, reduced rework from 7.2 percent to 1.1 percent, and removed a re-stacking step that had been part of every block.

The plant runs two foam lines and supplies PU blocks and cut sheets to mattress manufacturers in southern Vietnam. Blocks arrive at 1300 mm height and up to 2300 mm width, and the sheet range runs from 0.6 mm comfort layers to 70 mm support layers. Before the change, sheet cutting was handled by two older slicers, one of which had been in service for more than a decade.

The complaint was not speed. Mattress customers were rejecting layers that measured outside their tolerance at the block edges, while the same sheet measured inside tolerance at the middle. Operators compensated by cutting slightly thick, which pushed the problem downstream into lamination and quilt backing.

Two causes were identified during the audit:

• Table level: the older machine had a feed table that was out of level across the width, so thickness changed from one edge to the other.
• Block height: the machine could not take a full 1300 mm block, so each block was cut in two stages with a re-stacking step in between, adding a second set-up and a second chance for a thickness step.

Measured on 12 mm layers, the variation band was about ±0.15 mm, and rework on thin layers ran at 7.2 percent of output.

Three machines were shortlisted. Two were priced lower but were limited to 900-1100 mm block height, which would have kept the re-stacking step. The C717 was selected for three reasons: a 1300 mm cutting height that takes the full block, a stated ±0.05 mm precision, and a 50 m cutting length that allows a full block run without a mid-run re-load.

The 1200-2300 mm cutting width also matched the plant's block range, so no block had to be cut down before slicing.

Commissioning took three days. The first day covered foundation and levelling, the second blade tensioning and table alignment across the full cutting width, and the third operator training and a test run on production blocks. The alignment check was repeated after the first 8 hours of running, which is standard practice after a machine has settled under load.

• Full block height: the 1300 mm cutting height removed the re-stacking step and the thickness step that came with it.
• Table level across the width: alignment across the full 2300 mm removed the edge-to-middle variation that customers were rejecting.
• Blade tension and guides: correct tension with unworn guides kept the blade on line through the block.
• Speed set by thickness: thin layers run slower than thick ones, which keeps the blade cutting instead of pushing.

"The number that matters to us is the rework figure," said the plant's production manager. "We were cutting thick to be safe, and that cost us foam on every layer. Now we cut to the drawing and the customer measures it at the edge, not just in the middle."

The plant has since standardised its measurement routine: the first and last sheet of every block are measured, and the result is recorded against the batch. The maintenance team checks blade tension daily and table level weekly, and the alignment is re-checked after any change of block width.

The C717 is CE certified and available with delivery at 45 working days after downpayment. Blades, guides and remote commissioning support are supplied with each machine.