Case Study - ArvinMeritor Megalodon 400 LPM Flow Bench
ArvinMeritor, Inc. is a Tier One automotive supplier that produces body components, drivetrain systems, and ride control products for heavy-duty and commercial trucks, light trucks, passenger cars, and all-terrain vehicles. Among the company’s products is the driver-adjustable ArvinMeritor Dynamic Height Control (DHC) suspension that is standard equipment on the Pratt & Miller Corvette C6RS supercar. Pratt & Miller Engineering extended its relationship with ArvinMeritor by designing and manufacturing two custom-made flow benches for the company’s research and development laboratory. The second-generation unit, the Megalodon 400 LPM flow bench, is one of the largest capacity damper flow benches in the world. Previously existing flow benches could only measure 10 percent of the operational flow of military dampers produced by ArvinMeritor.

DESIGN:
Pratt & Miller engineers designed the Megalodon damper flow bench to handle a peak flow requirement of 400 liters per minute (LPM) at 3000 psi pressure. Electro-hydraulic proportional throttle valves control the flow through the damper valve being tested. Pratt & Miller’s flow bench design incorporated instrumentation, accumulators, control valves, control computers, data acquisition, cooling system, test fluid reservoir and storage, and an operator workstation.

DEVELOP:
The project’s test requirement was to have sufficient power at 3000 psi to ramp up to 400 LPM and back to zero in 60 seconds. Pratt & Miller specified a 200-horsepower hydraulic-to-hydraulic power unit (HPU) to meet this performance target.

The HPU used ArvinMeritor’s 2000-horsepower power supply as its primary power source. The HPU was based on a hydraulic vane motor capable of supplying 340 LPM at 3500 psi to the flow bench. The 400 LPM flow requirement was achieved with 3.5-gallon accumulators that supply additional flow as needed.

BUILD:
Pratt & Miller technicians fabricated the complete flow bench, including the framework, elevated and perforated steel flooring, T-track fixture mounting, fluid return channels, overhead lights, and overhead wire management. Pratt & Miller personnel installed the HPU, test circuit control valves, and instrumentation. ArvinMeritor supplied computer controls, electronic boards, and software, which were installed by Pratt & Miller. The project timeline was 13 weeks from kick-off to completion.

RACE:
Pratt & Miller tested the completed flow bench to maximum operating conditions and fully inspected the mechanical, hydraulic and electrical systems. Pratt & Miller supplied full documentation and specifications to ArvinMeritor.

WIN:
The Megalodon 400 LPM Flow Bench has significantly expanded ArvinMeritor’s ability to test dampers at high flow rates and pressures. By duplicating real-world operating parameters in a laboratory environment, the 400 LPM flow bench allows ArvinMeritor to design and manufacture superior quality dampers that meet and exceed its customers’ requirements.