CAGE-BEARING 3T7029 - Caterpillar

Glossary of Terms
Spring Adjustment:This adjustment provides the ability to control, or change, the amount of preload on the range spring. Some preload is always necessary to ensure that the pressure gauge pointer will always return to zero when test pressure is released.Adjustment of this preload spring will permit calibration of the gauge needle to the first cardinal number (100) on the gauge scale, whenever it is necessary. Span Adjustment:This is an adjustment to control the span (range) of travel for the pressure gauge pointer. This adjustment makes it possible to increase or decrease the span of pointer movement, to compensate for any variation in the spring rate within a system.A spring rate that is higher than nominal will require an increase in the span of pointer movement. A spring rate that is lower than nominal will require a decrease in the span of pointer movement. Rap:To tap on the top or side of the gauge. A standard gauge practice that takes out friction by "rapping" to make sure needle movement is complete.Additional Tools Needed
Some additional tools will be needed to perform the calibration and/or adjustment procedures. These additional tools are listed as follows:* 1U5230 Hand Pump 0-4150 kPa (0-600 psi), single acting.* A master test gauge for checking calibration points. The 5P8558 Pressure Gauge Calibrating Group can be used for this procedure. Field test gauges should have 1/2 to 1/4 percent accuracy. Laboratory test gauges should have 1/4 percent, or better, accuracy.* A standard screwdriver that will fit a 3/8" slotted head screw.* Torque screwdriver capable of a 0-0.68 N m (0-6 lb in) torque range.* Miscellaneous fittings for use in connecting the gauges and hoses to the pressure source.Procedure For Calibration Of 1U5793