Because the seam becomes the temperature limit of the whole assembly. Polyester softens around 250 degrees Celsius and nylon is similar. Stitch a 1000 degree fabric with either and you have built a 250 degree product.

What makes this failure particularly awkward is that the fabric is usually undamaged when it happens. The panel is intact, the seam has opened, and the protective cover has come apart while looking as though nothing was wrong with the material.

They describe temperature against duration, which is far more useful than a single number. Continuous service at 900 degrees means long term operation without degradation. 1450 degrees for 10 minutes is a sustained excursion. 1600 degrees for 15 seconds is peak survival. 1700 degrees is the softening point, where the material itself gives way.

Design against the figure that matches your exposure. A seam sitting permanently against a hot surface is governed by the 900 degree continuous rating, and the peak figures simply confirm a brief excursion will not destroy the assembly.

We supply 0.1 mm to 3.0 mm, and the whole range shares the same thermal performance. Diameter is selected against your fabric and your machine rather than against temperature.

Finer thread suits lighter fabric and finer stitch work. Heavier thread suits thick coated material and assemblies carrying mechanical load. Tell us the fabric thickness, the number of layers and the machine you are running, and we will recommend a starting diameter.

Almost always tension, speed or a worn thread path. Inorganic fibre has very low elongation, so it does not stretch to absorb tension spikes the way polyester does. A tension setting carried over from synthetic thread will break it.

Reduce tension considerably, slow the machine down, and check every guide and tensioner for wear grooves. A groove worn by years of synthetic thread will cut silica thread within a few metres. Those three checks resolve the large majority of breakage reports we receive.

The heat shrinkage rate is low and the thread remains stable through thermal cycling, which is a more important property in a thread than in a fabric.

The reason is that shrinkage in a fabric distributes across the whole panel, while shrinkage in a thread acts along the stitching line. A thread that shrinks puckers the assembly, distorts the fit and concentrates stress at every individual stitch, so the failure is progressive rather than sudden.

Yes, and a meaningful share of what we supply goes into non sewing applications. Winding electric heating elements, electrical insulation and cable filling, sealing within rubber hoses and gaskets, and reinforcement skeletons for fireproof tapes.

What those applications share with sewing is the requirement for a fine, non-combustible, electrically insulating fibre that holds dimensional stability under heat. The form suits several jobs beyond the one it is named after.

The same base chemistry at 96 percent SiO2 or above, produced at the same plant, presented as thread rather than as woven fabric.

That shared origin is the practical reason to buy both from one source. A seam and the panel it joins behave the same way under heat and shrink at the same rate, which is difficult to guarantee when the thread and the fabric come from different manufacturers with different processes.

No. The thread is non-asbestos, non-combustible and pollution free. It is a manufactured inorganic glass fibre with the non silica oxides chemically removed.

The non-combustible property comes from composition rather than from a chemical treatment, which means it cannot wear off or wash out over the life of the product.

Yes. We convert high temperature fabric into finished welding blankets, fire blankets, curtains, sleeves and insulation covers in our own workshops, stitched with this thread as standard.

For many buyers that is the better route. Setting up a workshop to sew inorganic thread reliably takes time and trial, and if your volume does not justify that investment, buying the finished item removes the problem entirely.

Yes, and for this product we strongly recommend it. Machine setup varies enormously between workshops, and the only reliable way to establish the right tension and needle combination is to run the thread on your own equipment.

Tell us the fabric and the machine when you request a sample so we can send the diameter most likely to suit. A sample in the wrong diameter tells you very little.

It depends on whether the diameter and spooling are standard or custom. A custom diameter or a non standard spool length needs its own production run, which raises both the minimum and the lead time.

Tell us the specification and your rough volume and we will confirm the exact figure with your quotation. If you are trialling first, we treat the trial quantity separately from the production requirement.

Payment is normally by T/T, structured as a deposit with the balance settled before shipment. We confirm the exact split with your quotation.

EXW, FOB, CIF and DAP terms are all available, so you can pick whichever fits how your freight is already arranged. If you have a nominated forwarder we will work with them directly.