R&A rigid resin-bonded filter cartridges are manufactured to the highest
international standards. They are produced with acrylic fibre of controlled diameter,
which are bonded together by a proprietary process using a phenolic resin.

The process used ensures that the filtration pores between the fibres are more open
near the outer surface of the cartridge and become progressively smaller towards the core
of the cartridge. This graded density construction enables the cartridge to trap coarser
particles near its outer surface, while finer particles are trapped nearer the core. The
phenolic resin impregnation strengthens the cartridge for use with fluid viscosities up to
15,000 SSU (3,200CKS).

This provides exceptionally good particle removal efficiency, which is the outstanding
feature of the cartridge. In addition, the rigid construction also ensures that the
cartridge will not deform under high operating pressure differentials. This means that
the cartridge exhibits a consistent and unvarying micron rating throughout its life and
does not suffer from deteriorating filtration efficiency and dirt unloading, which occurs
on filter elements of softer construction.

The addition of grooves greatly increases the cartridge surface area, thereby extending
even further the superior service life of the filter.

Depending on fluid temperature, the filter can withstand pressure surges of up to 10.3 Bar
(150 psi) across the cartridge.