External flush
Line shaft bearings/lower sleeve bearing should be lubricated with a continuous source of clean liquid at a rate of 1/4 to 1/2 GPM (0.95 to 1.9 l/min) per bearing at 10 - 20 PSI (69.0 to 137.9 KPa). A connection for external flush leading to the flush tubing to all bearings is provided above the mounting plate.

Internal cover flush
For the lower sleeve bearing, pump cover can be drilled for flush liquid supply. Process fluid must be clean and free of solids. This applies for short setting pumps only, maximum pump length of 36 inches (914.4 mm).

Bypass flush
For the line shaft bearings/lower sleeve bearings, flush liquid can be supplied from the pump discharge if the discharge pressure is sufficient. The flush tubing would be connected to the discharge pipe to provide the lubricating and cooling. Process fluid must be clean and free of solids.

Optional, additional bearing lubrication methods (for example, piping systems utilizing cyclone separators) are also available depending on the specific application. See cyclone separator arrangement at bottom right of page 6. Please consult the Fybroc factory or your local distributor for proper flush system selection.

Float type (Fig. 1)
Float-type level control utilizes field-adjustable polypropylene floats which contain mercury switches that actuate when the float becomes horizontal. Each float is secured to a PVC support pipe mounted to either a pit cover or a pump mounting plate, and each is supplied with 20 feet (6.1 m) of PVC cable.

Displacer type (Fig. 2)
Displacer-type level control is furnished with porcelain displacers connected to a flange-mounted switch by alloy wire and cable clamps. The wire and clamps are selected to suit the specific application and are normally 316SS, Alloy 20, Hastelloy-C or Monel. To prevent swirling liquids in the sump from improperly activating the switch, the displacers are frequently mounted inside a fiberglass stilling tube.

Probe type (Fig. 3)
Probe-type level control uses either solid rod or adjustable wire suspension electrodes, one for each actuation level. The circuit from an electrode to an external relay is made or broken when the liquid level touches or loses contact with that electrode. Electrodes are attached to a flange-mounted holder which in turn is mounted on either a pit cover or pump mounting plate.