TATA MOTORS uses ESI PAM-STAMP to shape a 3-ply steel/polymer sandwich oil sump to reduce noise
With simulation solutions such as ESI PAM-STAMP, simple and easy-to-manufacture part design proves very cost-effective and without compromise in terms of quality. The constructive and
positive team effort leads to unique cost-effective solutions that could have been discarded as unfeasible without the synergized effort of tool and product designers.Brian D’ CruzProgram Manager/ Tata Technologies
A Noise-Vibration-Harshness (NVH) study from Tata Motors shows that maximum engine noise comes from the oil sump. The objective is to reduce the noise from the oil sump.
Apart from changing the design of the part, they also looked at changing the material to a 3 ply " silent steel " for the design of new oil sumps. Tata Motors sought to synergize part geometry with the new intended material. Simulation allowed them to experiment, validate, and ultimately completely redefine and optimize their original concept
The objective of this project was to implement " silent steel " in the new engine oil sumps for upcoming vehicle platforms.Silent steel is a three-ply sandwich material in which two sheets of steel are held together by a layer of polymer. The resulting material displays inherent advantages in the Noise-Vibration-Harshness (NVH) characteristics, particularly significant in the immediate vicinity of the vehicle engine. Due to the layered nature of silent steel, its shaping requires careful de-sign and construction of the stamping tools.
Complex design due to multiple constrainsts
The initial sump design, as conceived by the Product Designer, needed to be prototyped for validation. Although the techniques used for prototyping, including heating and hammering blank sheets, provided fairly accurate product geometry, they were not quite
representative of the stamping process which would be implemented later on. Feasibility could not be assessed and tooling limitations could not be anticipated with the threeplay silent material. Due to the progress of vehicle development, additional constraints from interfaces and assembly accumulated.
Productivity boost with ESI PAM-STAMP
As constraints from the vehicle environment, from the tooling, and from the material itself were building up, over 25 different geometry modifications were needed before reaching a satisfactory final design that was good enough to be tried out physically with silent material. ESI PAM-STAMP was used to validate each design evolution until a defect-free feasible solution was reached.
Tackling multi-parameter constraints
The iterative process framing the part’s modifications had to take into account the following constraints:
. Tooled-up bed plate interfaces
. Oil capacity limitations
. Critical assembly clearances
. Mounting flatness
. Maximum thinning limitations
Hard Tooling Manufacturing
. Higher depth vs. Corner radius
. Side wall caving (quality issue)
. Drain mounting geometry
. Sharp profiles at the top corners
. Sudden sectional variations
The above images reveal the extent of the modifications required to take into account manufacturing needs with minimal compromises in assembly for the silent material.
Surely enough, the first physical prototypes in the stamping tool workshop matched very closely the modeled result.
Seemingly diverging manufacturing and vehicle-level constraints were resolved with simulation. Tata Motors 8 CPU DMP license resulted in a marked reduction in prototyping time and heavy gains in time-to-market. These achievements kindled a very high
faith in virtual prototyping abilities, leading to more daring designs much earlier in the product development phase.
About TATA MOTORS
Tata Motors is India's largest automobile company, with consolidated revenues of Rs.70,938.85 crores ($ 14 billion) in 2008-09. Through subsidiaries and associate companies, Tata Motors has operations in the UK, South Korea, Thailand and Spain. Among them is Jaguar Land Rover, the business comprising the two iconic British brands. It also has an industrial joint venture with Fiat in India. With over 4 million Tata vehicles plying in India, Tata Motors is the country’s market leader in commercial vehicles and among the top three in passenger vehicles. It is also the world's fourth largest truck manufacturer and the second largest bus manufacturer. Tata cars, buses and trucks are being marketed in several countries in Europe, Africa, the Middle East, South Asia, South East Asia and South America.
For more information visit Tata Motors