In cutting wheels and depressed center wheels, glass cloth is used to reinforce the wheel. These are referred to as reinforced grinding wheels. The glass cloth used for reinforcing the wheel is impregnated with phenolic resin.
The procedure for coating this glass cloth is as follows:
The glass cloth is dipped in liquid phenolic resin, dried at 80–100 C for 3–10 min, and after drying, is cut to the size of the wheel. The amount of the wet impregnated resin on the glass cloth is controlled from 30 to 50%.
The phenolic resin for this impregnation is mainly a resin consisting of a resole mixed with a novolac. Phenolic resin is designed such that the glass cloth is not tacky when stored and the adhesion is increased between phenolic resin and the grain.
The strength of glass cloth determines rotational strength. Therefore, the fabric strength and the type of weave are important. This effect demonstrates the safe rotational speed of a glass reinforced wheel of 4,500 m/min verses 3,000 m/min for a wheel without glass cloth reinforcement
Flake Phenolic Resin P2324 for Impregnating Glass Cloth are are produced by reacting formaldehyde with phenol under acid conditions with low free phenol and narrow MWD(Molecular weight distribution ).It is novolac resin and crash into flakes.
Specification:
Properties | Value | Test standard |
Curing time @150°C | 90-110s | GB/T24411-2009 |
Flow Distance@125°C | 35-45mm | GB/T24411-2009 |
Free-phenol | 0.5-1.5% | GB/T30773-2014 |
hexa content | 8-10% | ZJHM-QESP-01-2015 |
Water content | 0.5-2.0% | GB/T2683-2008 |
Screening 200mesh/0.074mm | 99% | GB/T24411-2009 |
Packing&Storage
the package is paper-plastics bag in 25KGS each one
The storage life of this product is several months in a cool and dry place in original closed bags