Shim Bonding (Connecting The Dots)

Connecting the dots between the past, present & future of bonding Ryan French & Haroon Mohmand, 2013.08.29

2013-08-29 TRELLEBORG GROUP 2


bond /bänd/ verb joined securely to another thing, esp. by an adhesive, a heat process, or pressure


de·bond /de-bänd/ verb occurs when an adhesive stops sticking (adhering) to an adherend or substrate material


6 2012-12-06 TRELLEBORG GROUP


bond (re-defined) /bänd/ verb

joined securely to another thing, esp. by an adhesive, a heat process, or pressure

passes the newly developed tap test (audible feedback must be in such a way as to not allow dead space sound in pre-defined areas outside of backplate features)

passes adhesive coverage (or disturbance?) test where the shim is removed and an approximated surface area determined by overlaying a circle dot matrix and counting the area that shows no visual adherence


Rubber (noise damping)

TRELLEBORG GROUP 10

Shim With Phenolic (1980’s – 1990’s)

Steel (structural integrity)

Phenolic Adhesive (Structural Bond)

2013-08-29

Rubber (noise damping)

TRELLEBORG GROUP 11

Shim With PSA (2000- present)

Steel (structural integrity)

Pressure Sensitive Adhesive (noise damping, not dependent on bond integrity)

2013-08-29

Temperature Effects on PSA’s

TRELLEBORG GROUP 12

Adhesive Temperature + -

2013-08-29

TRELLEBORG GROUP 13

Daily Operating Temperatures

2013-08-29

TRELLEBORG GROUP 14 2013-08-29

TRELLEBORG GROUP 15

0%

1%

2%

3%

4%

5%

6%

1980 - 2000 2000 - 2008 2008 - present

Acceptable Noise Percentage

2013-08-29

TRELLEBORG GROUP 16

Simple pad design • No insulator retention features • No insulator stress relief cuts • No bond surface area concerns • No pad/insulator shape concerns

Bonding substrate (backplate) • Sandblasted • Zinc coated • Liquid paint

Complex pad design • Large / multiple insulator retention features • Added insulator stress relief cuts • Bond surface area maximized • Shapes evaluated for bond integrity

Bonding substrate (backplate) • Liquid paint • Some powder paint

(1980’s – 1990’s)

(2000 – present)

2013-08-29


TRELLEBORG GROUP 18

Complex pad design

• Limited insulator retention features • Very few insulators with relief cuts • Bond surface area????? • Pad/Insulator shapes evaluated for bond integrity?????

Bonding Substrate (Backing Plate)

• 100% powder paint

(today)

2013-08-29

TRELLEBORG GROUP 19

Today’s end customers expect quieter brakes?

• Which is leading to warranty claims for even minor noise or potential noise.

• Is this leaving the investigation team puzzled, so they report all potential causes?

Lazy pad/insulator designs?

• Tighter packaging • Limited and/or poor retention features • Not utilizing relief slots • Limited bonding surface area • Poor pad/insulator shape

2013-08-29


Shim Bonding (Connecting The Dots)

Automotive