Quality
A sealant is judged twice: on the data sheet before the order, and at the joint two years later. The first is what we can document here. The second is why the methods below matter.
The tests behind the table
| Property | Method | Why it decides the outcome |
|---|---|---|
| Tensile strength | GB/T 528 | Whether the bead itself tears before the bond does |
| Elongation at break | GB/T 528 | How far the joint can move before the sealant fails |
| Tensile shear strength | GB/T 7124 | Load transfer between glass or metal and the bead |
| Shore A hardness | GB/T 531.1 | Soft enough to seal, hard enough not to sag |
| Skin time | GB/T 13477.5 | How long you can tool the bead before it skins |
| Sag resistance | GB/T 13477.6 | Whether the bead stays put on a vertical joint |
| Extrusion rate | GB/T 13477.4 | Gun time per cartridge on a cold morning |
| Density | GB/T 13477.2 | Coverage per kilogram, and therefore cost per metre |
| Volatile content | GB/T 2793 | Shrinkage after cure; solvent content in the drum |
| Cure rate | HG/T 4363 | Hours to handling strength at a given temperature and humidity |
| Elastic recovery | GB/T 13477.13 | Whether the joint closes again after movement |
Typical value vs batch result
Every figure on a model page is a typical value from the printed catalogue. It tells you what the product is designed to do; it does not tell you what is in the drum you receive. For that you need the batch record, and you should ask for it before approving a shipment — tensile, elongation and skin time at minimum.
This distinction is not pedantry. Two batches of the same model can differ by several percent in tensile strength and still be in specification; a customer who specified the typical value as a minimum has bought a problem.
Documents
Certificate scans are supplied with the quotation package — business licence, ISO 9001 and the product certificate for the model you are buying. Ask for the current set and we will send the documents naming the same legal entity as the invoice.
Quality system
The company works to ISO 9001. The certificate and its scope are available on request — ask for them together with the batch record so both can be checked against the same legal entity.