Why the joint decides your belt's life
On a teflon (PTFE) coated glass belt, the joint is almost always the first thing to fail — it is the one place where the smooth, non-stick surface is interrupted. Choosing the right joint type for your dryer or conveyor is therefore a maintenance decision, not a detail.
The four standard PTFE belt joints
- Bullnose overlap — both ends folded into a rounded nose that overlaps. Fast to fit, easy to re-lace on the machine; slight thickness bump at the joint. The everyday choice for medium duties.
- Scarfed (bias) overlap — the overlap is planed to a taper so the joint stays close to belt thickness. Smoother running over rollers and knife edges; the standard for solid belts and product-marking-sensitive duties.
- Pin / alligator joint — metal or plastic pin hinges joining the ends. Strong, openable for cleaning, good for mesh belts; the metal pin must suit the temperature.
- Endless (seamless) — woven or welded with no joint at all. The smoothest and strongest option for vacuum belt dryers; needs the belt made to final length.
Which joint for which duty?
- Vacuum belt dryers, food & pharma: endless or scarfed — anything that minimises marking and product trap points.
- Tunnel dryers, general drying: bullnose or pin — quick to fit, tolerant of temperature cycling.
- Mesh belts for high-air drying: pin joints — they preserve the open area.
- Frequent clean-downs: pin or bullnose — both can be opened for cleaning.
Specifying joints with Aurora
Tell us the dryer type, temperature, product and whether the belt passes over knife edges or vacuum plates — we will match joint type, thickness and edge treatment. Aurora TB belts are supplied with bullnose, scarfed, pin or endless joints, in mesh and solid constructions.
Need this specified for your machine?
Our engineers match construction, CFM and seams to your duty.