CD Industrial Group Inc.
Simulations and Hands-on Learning Challenges

Advanced Mobile with Load Sense Hydraulic Troubleshooting

Advanced Mobile with Load Sense Hydraulic Troubleshooting

2 Days

Is your diesel consumption too high? Is the hydraulic fluid hotter than normal? Is cylinder, motor or steering motion uneven or erratic? These symptoms point to a problem at the valve bank, the priority valve, the pump’s compensator or the load sense line.

Who should attend?

This level III course is for maintenance mechanics and technicians, and maintenance foremen/supervisors who are charged with the care of mobile equipment with load sensing hydraulic systems.

Load sensing systems use pressure feedback from the loaded actuators to constantly modify and control the pump’s displacement. The result is less wasted energy at the prime mover and greater flow accuracy within the system. These features along with priority valves and electronic proportional valves add complexity to the system.

Adjustments and the Ten Step Troubleshooting Process are covered along with plenty of schematic reading practice specific to load sense systems.

This two-day course is taught with live hydraulics training panels, circuit simulation software, oilfield and mobile machinery schematics and on-screen simulations, and through instructor guided hands-on study of individual cut-away hydraulic components.

Learn How To:

  • Explain “load sense” or “flow compensating” principles
  • Analyze load sense circuit schematics
  • Adjust load sense pumps and set the stand-by pressure
  • Identify priority valve features and ports
  • Describe steering valve features
  • Analyze common electronic proportional valves
  • Troubleshoot common load sense system problems
  • Work safely around hydraulic systems

Load Sensing Theory

Objective: Explain the principles of load sensing (flow compensating) systems

Activity: Predict fluid and component behaviours in load sensing systems

What does it mean to 'sense the load'? Find out in this course.

Joysticks and Pilot Controllers

Objective: Analyze joystick and complete valve pilot networks

Activity: Interpret schematics for logic conditions and pump flow allocations

Figure out when the pump flows are combined for functions and when they are separated. Knowing what normal looks like, helps with troubleshooting.

Loader Ride Control Circuits

Objective: Analyze valve and ECM logic for ride control circuits

Activity: Determine what speeds activate and deactivate ride control

Know how to analyze a weak or spongy boom lift circuit and where to look for the issue

Load Sensing Systems Design

Objective: Analyse circuit components and their relationships

Activity: Interpret symbols and component connections on typical systems

The components and their relationships,..symbols and schematics

Load Sensing Directional Valves

Objective: Explain the features of common load sense proportional directional valves

Activity: Interpret catalogue data to determine valve port, functions/features

Master electric/electronic-over-hydraulic valve piloting

Load Sensing (Flow Compensating) Pumps

Objective: Identify pump compensator connections and functions

Activity: Determine pump control response to various machine load scenarios

The compensator connections and functions, and the pump's response to load conditions

Mobile Priority Valves

Objective: Identify priority valve features and ports

Activity: Sketch a diagram that shows how to favour machine steering above all other functions

The priority valve watches for pressure drops that threaten steering and brakes. Find out how this works!

Mobile Steering Valves

Objective: Explain steering valve servo functions

Activity: Determine potential leakage paths through shock relief and anti-cavitation valves

Learn it cold! How the hand metering unit proportions a precise amount of fluid.

Specialized Pressure Control Valves

Objective: Analyze the function of combination pressure control valves

Activity: Describe the responses of pressure controls and the signals to the pumps

Find out why standby pressure at idle may be higher than the load sense margin pressure

Flow Stabilizing Function

Objective: Describe how load sense systems regulate flow

Activity: Predict pump response to prime mover RPM variance

Find out how the system responds to fluctuating speeds at the prime mover

Circuit Troubleshooting

Objective: List common faults and remedies in load sense circuits

Activity: Diagnose faults on simulated systems and list the causes

Common faults and remedies in load sense circuits

Safety

Objective: List common hydraulic hazards and safe procedures

Activity: Determine procedures for safe work on hydraulic systems

Procedures for safe work on hydraulic systems

Where to go from here?

Advanced Mobile with Load Sense is part of a general hydraulics training plan. Other courses at the same level include Hydrostatic Drive Troubleshooting Boot Camp, and Advanced Hydraulics Troubleshooting & Motion Control.