Introduction to Hydraulic Durability and Chassis Testing

What is Hydraulic Durability Testing?

Hydraulic durability testing evaluates a component or system's reliability and performance under input from a hydraulically driven test rig by simulating a lifespan under various conditions. MGA’s Hydraulic Durability group has established itself as a leader in validating components and assemblies across various industries, including:

• Automotive (OEM and aftermarket)
• Off-road
• Aerospace (nondestructive and structural testing)
• Public transport (bus/train)
• Space
• Military

MGA's Hydraulic Testing Capabilities

Testing Facility Overview

MGA has been conducting hydraulic durability (“HD”) testing for over 20 years, and in that time has developed a national reputation for high-quality testing services. MGA has performed an abundance of projects on systems and components, including frames, chassis, suspensions, exhausts, trailer hitches, seats, and other interior and exterior components. These durability tests have been conducted for a wide range of foreign and domestic OEMs and their suppliers.

To meet industry demands, MGA has significantly expanded its capabilities over the past two decades, commissioning multiple new labs across our North American locations. Presently, MGA operates several hydraulic labs in Michigan, along with facilities in South Carolina, Alabama, California, and Canada. MGA’s laboratories are equipped with a comprehensive array of hydraulic equipment, ranging from Multi-Axis Simulation Tables (MAST) to custom multi-input setups.

Test Equipment and Systems

Hydraulic Test Benches and Actuator Life Cycle Testing

At MGA, we have a wide array of hydraulic actuators, ranging in size from 2.2 kip to 135 kip force capacity. For high-speed applications, MGA also has hydraulic cylinder testing with 3-stage valves that are capable of 100+ in/s. We can recreate most environmental conditions, including hot, cold, humid, and sun-exposed conditions. For MAST rigs, we have environmental chambers, semi-anechoic chambers, and some with both capabilities. MGA has the latest control systems, including MTS FlexTest® controllers and software.

Hydraulic Power Systems

The Hydraulic Durability Group at MGA operates an extensive testing infrastructure, with each lab featuring sizeable bed plates with reaction masses and up to 400 gpm of pumping power.

Multi-Axis Simulation Tables (MAST)

MGA has 18+ MASTs across its network of labs with different rigs to meet any application. Our tabletop sizes range from 5'x7' to 6'x8'. 

Component Experience

• Spare ties 
• Seating 
• Cockpits
• Roof systems 
• Exhaust components
• Exterior components
• Full frame/vehicles

This extensive knowledge has led to numerous successful single and multi-axis projects using MAST systems. 

Available Test Capabilities

• Single-axis 
• 3 DOF
• 6 DOF vibration durability 
• Dedicated dual MAST setups for exhaust and chassis durability 
• Customer-built 7 actuator systems for full vehicles (up to semis)
• Buzz, squeak, and rattle (BSR) sound evaluations. 
• Environmental conditioning is available for most testing 

For more information on vibration capabilities, visit Vibration Testing | MGA Research Corporation.

Types of Hydraulic Durability Tests

Fatigue Testing

Static and Cyclic Loading

MGA can conduct strength and durability testing on a wide array of vehicle components, including full/partial frames, axles, trailer hitches, recovery/tow hitches, and suspension components such as sway bars, cradles, control arms, knuckles, hubs, springs and dampers, link bars, and more. Common test types include:

• Static strength
• Permanent set / deformation
• Cyclic fatigue
• Block cycle fatigue
• Torsional strength / fatigue
• Environmental conditioning for all testing types

Real-World Simulation

MGA has been conducting real-time simulation testing since the group's inception, thereby accumulating unparalleled expertise. MGA uses RPC ® Pro software and sensors for both control and response data, including load cells (50 lbf to 200k lbf), accelerometers (single and tri-axial), string pots (up to 30 inches), strain gages (linear and rosettes), and many more to recreate vehicle behavior from the real world in the lab. This allows the opportunity to accelerate testing through proving ground multipliers, reducing a 150k-mile use case that would typically take 6 months down to just a few weeks.

Advanced Testing Services – Non-Destructive Inspection

MGA uses Nondestructive Dye Penetrant Inspections (DPIs) to identify and track issues through testing before critical failure. The customer determines inspection intervals and areas of concern. MGA carefully photographs the entire inspection zone to document the component's condition at the current stage of testing. Any issues or cracks found are photographed next to a calibrated scale to track their progression. Common uses of DPIs include manufacturing process validation, crack nucleation, cascade failure visualization, and weld integrity evaluation.

Industry Standards and Compliance

The engineers and project managers in the HD group have decades of experience managing validation plans for North American, European, and Asian OEMs and suppliers. We cater to a wide range of industries, including both automotive and aerospace. Current standards we test to include:

• SAE J684
• SAE J2638
• Custom test modes

Data Acquisition and Test Results

Comprehensive Data Collection

MGA can record data for over 100 channels, including accelerometers, load cells, string pots, other linear transducers, strain gauges, pressure transducers, thermocouples, and torque cells, and can acquire up to a full vehicle for road load data acquisition (RLDA). Other devices that can be recorded consist of CAN, OBD, GPS, and wheel force transducers (WFTs). 

MGA has experience in custom instrumentation, enabling the development of innovative methods to capture unique data requests. Custom transducer examples include engine mount, cab mount, steering or suspension load using strain gages, frame twist (also using strain gages), and steering angle using a string pot.

Reporting and Documentation

MGA conducts detailed documentation throughout all test series. This includes intermittent video recording to display the current state of a moving component or detailed photographs to highlight component condition, such as cracking or other failures. All photographs, as well as data collection and any visual finds, are documented in a detailed test report provided to our customers upon request.

Data Reduction and Damage Analysis

Durability-related testing is typically considered a time-compressed simulation of a lifetime of real-world usage. In most cases, actual data, either in the form of strain or acceleration, is recorded while driving on a series of roads that are considered to make up that lifetime. Following the data collection, several steps are typically used to go from the field to the lab, including:

• Data verification and repeatability by reviewing multiple datasets of the same durability loop.
• Calculating damage to determine non-damaging events of the proving ground schedule.
• Removing dead time and low-amplitude data of the damaging events while maintaining an agreed-upon damage retention (typically 95% of the baseline).
• Establishing a sequence playback using proving ground multipliers for an in-lab simulation.

Getting Started with MGA

With our network of 10 facilities across North America, our teams are equipped with comprehensive equipment to meet your needs. Our extensive range of hydraulic equipment complies with current industry standards. We continually work to ensure accuracy and confidence in your testing requirements. To contact an engineer, please fill out the contact form on our website. 

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