For easy of Operation & Maintenance, all Rock Crusher Lubrication System include their own monitoring devices, SIGHT GLASSES or VIEW PORTS in the reservoir for oil level, FLOW METERS in the oil lines and/ or VISUAL ACCESS to the discharge point of the oil circuit. This is to allow the operator to gauge the oil flow visually. And finally as mentioned before the pressure gauges.

The location of these gauges in the circuit is important. The best place is between the OIL PUMP and the FILTERS. Here the pressure readings will monitor both pump performance and the condition of the filters. If the pressure climbs then the filters are probably dirty and should be cleaned. If the pressure drops then the mechanical condition of the pumps should be checked.
If the pressure becomes too low then a FLOWSWITCH that is normally in the line will automatically shut the crusher down.  This switch will not allow the crusher to be restarted until the pressure is back to normal.

The fact that a crusher has this flow switch in the oil circuit should not become an excuse for the operator not monitoring the line pressure. A switch can fail. Also conditions may be present where the pressure is slowly dropping because of a slow leak. If it is caught early a lot of down time or damage to the equipment can be prevented.

There is another item that will indicate problems developing before they happen, and this should be watched as well. It is simply a SCREEN that is placed under the discharge of the oil as it is returned to the HOLDING TANK. The purpose of the screen is to catch foreign objects that are in the oil. If there is excessive wear on a bearing then filings from it may show up on the screen. Of course this would have to be reported to the supervisor in charge.
One problem that I have mentioned but haven’t discussed is COLD OIL. This is-usually a problem only on startup and should be looked at on your prestart-up circuit check. Why it isn’t a problem while operating is that the heat generated from the crusher is enough to keep the oil warm. If it is too cold before start up, the problem will be in the heaters, they may simply be turned off or there may be an electrical fault. Both are easily verified.