Norglide

Innovation is our nature

NORGLIDE®

Maintenance free bearings

• Minimum coefficient of friction • Low wear and size-ability • Eliminates noise • Vibration damping • Heavy metal free

NORGLIDE®-advantages at a glance ö Minimum coefficient of friction for solid materials ö Maintenance free and self-lubricating ö Minimum stick-slip effect ö High pU (PV) for absolute dry-running and stability ö Takes up edge loading and compensates for misalignment ö Eliminates noise ö Vibration damping ö No water absorption ö Good formability ö Excellent wear resistance ö Temperature resistant

2 • Saint-Gobain Performance Plastics

Table of contents NORGLIDE® range of bearings

4–5

NORGLIDE®-Types

6 – 11

Compounds

12

Coefficient of friction

13

Life expectancy of NORGLIDE® bearings

14 – 19

Design of the bearing

20

Tolerancing

21

Sizing

22

Torques

23

Installation of NORGLIDE® bearings

24 – 25

Measuring NORGLIDE® bearings

26 – 27

Corrosion resistance

28 – 29

Quality

30 – 31

Practical Application

32 – 35

Saint-Gobain Performance Plastics worldwide 36

3

The range of NORGLIDE® bearings Fluoropolymers have been used as bearing materials for over 50 years. Since its discovery in 1938, Poly Tetra Fluoro Ethylene has continuously been developed and improved. The addition of appropriate fillers gives the material specific properties which alter its strength and coefficient of friction and enable it to perform a large variety of tasks. Tape bearings modified this way (a blank of PTFE tape formed under temperature) are the origin of our bearing program.

By encapsulating a metal fabric into PTFE, an important step forward was made: NORGLIDE® MP is a plastic material which allows the large-scale production of bearings. For the first time our customers are able to produce a specific torque or clearance by sizing the bearing. This is also possible with NORGLIDE® S which uses stretch-

We develop customized solutions that will help our clients succeed.

We offer a full line of high-performance bearing materials for the most diversified requirements.

Selecting the proper material for the individual application is the core of our cooperation with the customer.

You as the designer can count on us when it comes to providing custom service.

ed metal instead of the metal fabric.

The combination with a steel shell makes it possible to increase the load bearing capability significantly. NORGLIDE® T combines steel and tape to provide noise and vibration damping properties and light-weight construction. Similarly when bonded to steel NORGLIDE® MP turns into NORGLIDE® M, NORGLIDE® S into NORGLIDE® SM. Both materials maintain their sizing capability to a large extent with the capability of higher loads. They take up edge loading and compensate for misalignment. NORGLIDE® materials with a steel thickness ≥ 0.5 mm are suitable for producing a press-fit in the housing.

The latest innovation is NORGLIDE® PRO the PTFE bearing with best load-carrying capabilities known today. With its complex composition - steel plate, structured bronze layer with encapsulated PTFE sliding layer – its load-bearing capability is almost twice as much as that of NORGLIDE® T, M and SM.

NORGLIDE® MP

4 • Saint-Gobain Performance Plastics

NORGLIDE® S

NORGLIDE® T

NORGLIDE® PRO

NORGLIDE® SMTL

“ „ We specialize in low coefficients of friction, low wear and size-ability.

NORGLIDE® M

NORGLIDE® SM

5

NORGLIDE® MP and S NORGLIDE® MP and S Maintenance free, flexible bearing tapes NORGLIDE® MP and NORGLIDE® S are maintenance free bearing materials made of a metal support structure and a wear-resistant PTFE compound which offer high load capabilities. This combination of materials enables easy manual or automatic

Standard thickness table NORGLIDE® MP

processing and installation. NORGLIDE® MP and NORGLIDE® S can be adapted to

Nom. thickness

many applications, including severe chemical environments.

The materials allow excellent sizing so that an interference fit of the bearing to the shaft can be designed to produce particular torques or eliminate play.

Material Structure

(mm)

CuSn 6 Fabric

1.4401 Fabric

0.48

ö

ö

Availability

0.78

ö

ö

The support structure is available in either tin bronze, stainless steel or aluminum. The

0.98

ö

standard PTFE compound contains glass fibers and graphite. Special PTFE compounds are available on request. Fabricated parts include die-cuts, rolled cylinders, flanged cylinders and deep-drawn bearings. NORGLIDE® MP and NORGLIDE® S can be prepared for bonding (etched one side). They can be supported or backed with steel or plastics.

NORGLIDE M ®

NORGLIDE® M Maintenance free bearings with steel backing

Standard thickness table NORGLIDE® M Nom. thickness (mm)

Material Structure

CuSn 6 Fabric Steel backing ö

NORGLIDE® M is a composite material of NORGLIDE® MP bearing tape and steel

0.75

backing. This combination of material improves load capabilities while maintaining

1.0

ö

the characteristics of NORGLIDE® MP, especially its sizing capability.

1.5

ö

The bearings can be designed to be clearance free. Bearings of 1 mm of wall thickness or greater can be produced with an interference fit in the housing. Various methods are available to protect the steel shell from corrosion.

Availability The standard PTFE compound contains glass fibers and graphite. Special PTFE compounds are available on request. Fabricated parts include rolled bearings with or without an axial flange, deep-drawn bearings and die-cuts. The steel shell and mesh can be offered in stainless steel for chemically harsh environments.

6 • Saint-Gobain Performance Plastics

1.57

Stainless steel fabric Stainless steel backing

ö

PTFE compound Metal fabric

Material properties Norglide® MP SG Test Procedure Maximum permissible specific bearing load at RT SG PL 0044 Coefficient of friction at RT on steel with ≥ 58 HRC at 4.8 N/mm2 and 0.058 m/s at 70 N/mm2 and 0.0065 m/s

SG PL 0003 SG PL 0003

Deformation under load (230C, at 100 N/mm2, 1 h)

SG PL 0015

Value

N/mm2

100 to 140

0.09 to 0.19 0.06 to 0.10

Maximum continuous operating temperature K factor at RT on steel with ≥ 58 HRC

Units

µm

30 ≤ x ≤ 90

°C

260

10-6mm3/Nm 0.12 to 0.18

SG PL 0003

The above mentioned performance values were measured in laboratory tests.

They must not be considered as a specification for design.

Material properties Norglide® M SG Test Procedure

Units

Value

Maximum permissible specific bearing load at RT

SG PL 0044

N/mm2

180 to 220

Coefficient of friction at RT on steel with ≥ 58 HRC at 4.8 N/mm2 and 0.058 m/s at 70 N/mm2 and 0.0065 m/s

SG PL 0003 SG PL 0003

Deformation under load (230C, at 100 N/mm2, 1 h)

SG PL 0015

Maximum continuous operating temperature K factor at RT on steel with ≥ 58 HRC

SG PL 0003

0.11 to 0.19 0.065 to 0.1

µm

≤ 30

°C

180

10-6mm3/Nm 0.12 to 0.18

The above mentioned performance values were measured in laboratory tests.

They must not be considered as a specification for design.

PTFE compound Metal fabric Steel backing

7

NORGLIDE® SM NORGLIDE® SM Maintenance free bearings with steel backing NORGLIDE® SM is a composite material of compounded PTFE, bronze stretched metal and steel backing. This material structure combines the bearing characteristics of a PTFE compound tape with the sizing capabilities of stretched metal. These bea-

Standard thickness table NORGLIDE® SM

rings can also be designed to be clearance free. Bearings of 1 mm wall thickness or available to protect the steel shell from corrosion.

Nom. thickness (mm)

Availability

0.75

The standard PTFE compound contains carbon and graphite. Special PTFE com-

1.00

ö

pounds are available on request. Fabricated parts include rolled bearings with or

1.50

ö

bigger can be produced with an interference fit in the housing. Various methods are

Material Structure

CuSn 6/Stretched metal Steel backing ö

without an axial flange, deep-drawn bearings and die-cuts.

NORGLIDE® SMTL ®

NORGLIDE SMTL Maintenance free bearings with steel backing

Standard thickness table NORGLIDE® SMTL Nom. thickness (mm)

NORGLIDE® SMTL is a composite material of compounded PTFE, bronze stretched

Material Structure

CuSn 6/Stretched metal Steel backing ö

metal and steel backing. In contrast to NORGLIDE® SM, the bronze stretched metal

0.50

in NORGLIDE® SMTL is separately precompressed and the PTFE compound tape is

0.75

ö

thinner, which improves load capabilities while reducing tolerance compensation

1.00

ö

compared to NORGLIDE® SM. Bearings of 0.75 mm of wall thickness or bigger can be produced with an interference fit in the housing. Various methods are available to protect the steel shell from corrosion (page 28).

Availability The standard PTFE compound contains either Ekonol® graphite or carbon and graphite. Special PTFE compounds are available on request. Fabricated parts include die-cuts, rolled cylinders, flanged cylinders and deep-drawn bearings.

8 • Saint-Gobain Performance Plastics

PTFE compound Stretched metal Steel backing

Material properties Norglide® SM SG Test Procedure Maximum permissible specific bearing load at RT SG PL 0044 Coefficient of friction at RT on steel with ≥ 58 HRC at 4.8 N/mm2 and 0.058 m/s at 70 N/mm2 and 0.0065 m/s

SG PL 0003 SG PL 0003

Deformation under load (230C, at 100 N/mm2, 1 h)

SG PL 0015

Value

N/mm2

150 to 200

0.13 to 0.30 0.07 to 0.10

Maximum continuous operating temperature K factor at RT on steel with ≥ 58 HRC

Units

µm

≤ 50

°C

180

10-6mm3/Nm 0.16 to 0.70

SG PL 0003

The above mentioned performance values were measured in laboratory tests.

They must not be considered as a specification for design.

Material properties Norglide® SMTL SG Test Procedure Maximum permissible specific bearing load at RT SG PL 0044 Coefficient of friction at RT on steel with ≥ 58 HRC at 4.8 N/mm2 and 0.058 m/s at 70 N/mm2 and 0.0065 m/s

SG PL 0003 SG PL 0003

Deformation under load (230C, at 100 N/mm2, 1 h)

SG PL 0015

Maximum continuous operating temperature K factor at RT on steel with ≥ 58 HRC

SG PL 0003

Units

Value

N/mm2

240 to 300

0.15 0.10

µm

≤ 15

°C

180

10-6mm3/Nm 0.10

The above mentioned performance values were measured in laboratory tests.

They must not be considered as a specification for design.

PTFE compound Stretched metal Steel backing

9

NORGLIDE® T NORGLIDE® T Maintenance free bearing with metal backing NORGLIDE® T is a composite material of compounded PTFE tape on a metal shell. This material structure enables machining of the bearing in the housing – which is an alternative to the sizing process - to obtain tightest tolerances on the inside diameter.

Standard thickness table NORGLIDE® T Nom. thickness (mm)

Steel

0.50

ö

0.75

ö

ö

ö

1.00

ö

ö

ö

pounds are available on request. Finished parts include rolled bearings with or

1.50

ö

without an axial flange (nominal thickness 0.5 mm and 0.75 mm), deep-drawn bear-

2.00

The very thick PTFE layer isolates noise and allows the design of clearance free bearings. Bearings of 0.75 mm thickness or bigger can be produced with an interference fit in the housing. Various methods are available to protect the steel shell from corro-

Material Structure

Stainless steel

Alu

sion.

Availability

ö

The standard PTFE compound contains carbon and graphite. Special PTFE comö ö

ings and die-cuts. The metal backing is available in steel, aluminum or even stainless steel for chemically harsh environments.

NORGLIDE® PRO NORGLIDE® PRO Maintenance free bearing with steel backing NORGLIDE® PRO is a steel material with a polygon-structured bronze layer on one side. Encapsulated in the polygon structure is a sliding layer of compounded PTFE tape. This combination of materials provides much higher load-carrying capabilities.

The material is sizable and can be adapted to any clearance required for the specific application. The whole range of NORGLIDE® PRO thicknesses can be designed with a press fit in the housing. Several methods are available to protect the metal backing from corrosion.

Availability PTFE compounds are available with carbon or EKONOL®. Fabricated parts include rolled bearings with or without an axial flange, deep-drawn bearings and die-cuts.

10 • Saint-Gobain Performance Plastics

Standard thickness table NORGLIDE® PRO Nom. thickness (mm)

Material Structure

Steel

0.50

ö

0.75

ö

1.00

ö

PTFE compound tape Metal backing

Material properties Norglide® T SG Test Procedure

Units

Value

Maximum permissible specific bearing load at RT

SG PL 0044

N/mm2

180 to 200

Coefficient of friction at RT on steel with ≥ 58 HRC at 4.8 N/mm2 and 0.058 m/s at 70 N/mm2 and 0.0065 m/s

SG PL 0003 SG PL 0003

Deformation under load (230C, at 100 N/mm2, 1 h)

SG PL 0015

µm

≤ 30

Maximum continuous operating temperature

SG PL 0048

°C

180 to 260

K factor at RT on steel with ≥ 58 HRC

SG PL 0003

10-6mm3/Nm 0.10 to 0.90

0.10 to 0.30 0.06 to 0.065

The above mentioned performance values were measured in laboratory tests.

They must not be considered as a specification for design.

Material properties Norglide® PRO SG Test Procedure Maximum permissible specific bearing load at RT SG PL 0044 Coefficient of friction at RT on steel with ≥ 58 HRC at 4.8 N/mm2 and 0.058 m/s at 70 N/mm2 and 0.0065 m/s

SG PL 0003 SG PL 0003

Deformation under load (230C, at 100 N/mm2, 1 h)

SG PL 0015

Maximum continuous operating temperature K factor at RT on steel with ≥ 58 HRC

SG PL 0003

Units

Value

N/mm2

400

0.19 to 0.20 0.11 to 0.12

µm

≤5

°C

260

10-6mm3/Nm 0.18 to 0.20

The above mentioned performance values were measured in laboratory tests.

They must not be considered as a specification for design.

PTFE compound Bronze Steel

11

Compounds Pure (virgin) PTFE is a soft, electrically insulating material with a minimum coefficient of friction for solid materials.

With the addition of fillers, properties like creep or electrical conductivity can be optimized while maintaining the excellent sliding characteristics of PTFE. Some of these compounds are discussed here:

Glass fiber/graphite Compound Glass fibers increase the load carrying capability and reduce wear and creep.

Graphite minimizes initial wear.

Carbon/ graphite Compound Carbon assumes a similar function as glass fibers, but is less abrasive on the mating contact surface.

EKONOL® Compound This compound combines the outstanding wear resistance of EKONOL® with the low initial wear of graphite. It is less conductive than the carbon/graphite compound.

Electrically Conductive Compounds With the addition of selected fillers we can tailor the electrical conductivity of the bearing. The total electrical resistance depends on the contact surface between the bearing and shaft, size, active surface load and the material thickness.

Electrically conductive bearings are used for electrostatic discharge, not for conducting electrical current. They are most valuable in the cathodic dip-coating of assemblies

Non-Conductive Compounds Electrically non-conductive bearings reduce paint build-up on the bearing surfaces and help improve paint quality.

12 • Saint-Gobain Performance Plastics

PTFE/Steel 100 Cr6 T= 23°C

Coefficient of friction

T= 70°C

0,2

0,62

p

3,1

(M Pa )

µ dyn

0,1

6,2 0 10

10 -1

10 -3

0,17

0,017

0,00017

10 -5

U (m/min) 0,0000017 m/sec According to Research Report 83, Bundesanstalt für Materialprüfung, Berlin July 1982

Coefficient of friction The coefficient of friction of a composite material is not a constant. It is dictated by the materials of the mating contact surfaces and by the roughness of the harder one. With combinations that have very different strength values (such as polymer with steel) the coefficient of friction also depends on the load. In addition, due to the polymers’ strong tendency to change all mechanical properties under temperature, the coefficient of friction is also affected by speed and ambient temperature. The above shown graph demonstrates the influence of speed and load on the coefficient of friction of a PTFE/steel bearing (100 Cr6 1.3505). The coefficient of friction drops as load increases and as speed decreases. It also changes as the bearings wear.

During the wear-in period NORGLIDE® bearings are shortly exposed to higher wear. A polymer transfer layer forms on the metal contact surface.

After wear-in a relatively constant performance range is found which is controlled by the pure PTFE compound layer.

With bronze reinforced NORGLIDE® types, the coefficient of friction increases slightly after prolonged service due to the exposure of bronze to the mating surface. The bronze may then have contact with the shaft. This factor should be taken into account when selecting materials for applications with higher admissible wear or high pressure.

The coefficient of friction of NORGLIDE® T stays constant over the whole service life. With NORGLIDE® PRO XL the bronze layer can be reached after a short period and the coefficient of friction grows gradually.

Generally speaking, the coefficient of friction of NORGLIDE® materials is outstandingly low in comparison with other polymer bearings, due to the use of PTFE as main component in the bearing surface.

13

Life expectancy of NORGLIDE® bearings Specific bearing load p and sliding speed U The life expectancy of NORGLIDE® bearings is essentially dictated by the environment of the particular application. Simply stated, the life expectancy is dertermined by the specific bearing load p [N/mm2] and the sliding speed U [m/s] of the application range. The product of both values is called pU (pV).

Equation 1

pU = p · U

For some bearing materials pU limiting curves exist. In addition to these, parameters typical of the particular application (bearing clearance, roughness and hardness of the mating-contact surface, ambient temperature, etc.) affect the position of the pU limiting curve.

1000 T-carbon/graphite M-glass/graphite PRO

100 Load [MPa]

MP

10

1

Graph A

0.1 0.001

0.01

0.1

1

10

Speed [m/s]

50 45 Deformation [µm]

40

Graph B

35 30 25 20 30 100 30 100

15 10 5

M Pa, 23 °C M Pa, 23 °C M Pa, 100 °C M Pa, 100 °C

0 0.01

0.1

1

10

100

1000

10000

Time [h]

Graph C

Temperature

1.2 1.0

KT

0.8 0.6 0.4 0.2 0.0 0

50

100

150

200

Temp [°C]

14 • Saint-Gobain Performance Plastics

250

Graph C shows the influence of temperature on the life expectancy which is 40 % lower if the bearing is exposed, for instance, to a temperature of 100°C (correction factor KT).

In principle, NORGLIDE® bearings can be used below the curves shown in graph A. Oscillating motions, intermittent operation, oil lubrication or low demands on the life expectancy can achieve higher limit values.

The static maximum bearing load depends on the material and describes the maximum possible load the bearing can bear without sliding motion before it is destroyed. When designing the pivot point, the deformation of the bearing by this load is to be taken into account. Due to the visco-elastic behavior deformation depends on nominal force, time and temperature (see graph B).

The dynamic maximum bearing load defines the load limit for the application (sliding speed > 0) above which the bearing probably should not be used. The load limit also depends on the sliding speed (see graph A). The permissible load decreases as the sliding speed increases.

The pU limiting curves shown here have been determined with continuously rotating shafts in stationary NORGLIDE® bearings. The pU operating range increases as the energy generated by friction and ambient temperature is absorbed by adequate cooling.

NOTE: pU = pV

Mating-contact surface Life expectancy is influenced also by parameters such as material (table 1), hardness (graph D) and roughness (graph E) of the mating-contact surface.

Adverse values of hardness and roughness promote early wear, i.e. life expectancy of a bearing is substantially lower if shafts with a hardness value well below 50 HRC are used.

Table 1 Steel Low-corrosion steel Hard-chrome plated steel Gray cast iron Hard-anodized aluminum

KJ, Mat 1 1 1,5 1 1

1.2 1.0 KJ,HRC

Shaft material

0.8 0.6 0.4

Same applies to roughness values well above Ra = 0,4 µm.

Low Ra values (Ra < 0,1 µm) lead to increased wear as well.

0.2 0.0 20

30

40

50

Graph D

Load type 1.2 1.0 0.8 KJ,Ra

Dynamic loads, i.e. loads alternating in size, reduce the life expectancy of the bearing. This fact is taken into account when determining the dynamic factor or correction factor for the dynamic load Kdyn. For correcting the life expectancy under dynamic load, refer to graph F and proceed as follows:

60

Hardness [HRC]

0.6 0.4 0.2 0.0 0.0

0.2

0.4

0.6

0.8

1.0

Ra [µm]

1. Select the number of required load cycles

Graph E

2. Read Kdyn 3. Use Kdyn for calculating the life expectancy

With radial bearings, distinction is also made between point load and peripheral load, depending on whether the load is applied in a single point or is rotational. This influence is considered in correction factor Kf : Point load Kf = 1 Peripheral load Kf = 2

1.2 1.0 0.8 Kdyn

For applications without dynamic load, use Kdyn = 1 (uniform load).

0.6 0.4 0.2 0.0 103

104

105

106

107

Load cycles

Graph F

15

Life expectancy of NORGLIDE® bearings Wear depth ( ∆ hmax) and wear factors (KW factor) The two wear sizes described in this chapter depend on the material or system used. Wear depth ∆ hmax is the thickness of the bearing layer which, when worn, indicates the end of the bearing life. Wear factor is the volume per energy unit (load and sliding distance) worn by the application. The maximum permissible wear depths of selected bearings materials and the related wear factors are listed in table 2.

Table 2 Bearing material

hmax [µm]

NORGLIDE® MP NORGLIDE® M NORGLIDE® SM NORGLIDE® SMTL NORGLIDE® T NORGLIDE® PRO

280 280 250 100 250 100

0.12 - 0.18 0.12 - 0.18 0.16 - 0.70 0.10 0.10 - 0.90 0.18 - 0.20

With the above mentioned parameters and the related correction or wear factors the life expectancy can be calculated by the following equation:

Equation 2

tmax =

hmax Kw · pU · 3.6

Kf Kdyn KT KJ,HRC KJ,Ra KJ,Mat

Life expectancy The influences described here have been calculated empirically and other unconsidered factors typical of the particular application may be of importance. Therefore, the theoretically calculated life expectancy of NORGLIDE® bearings is an estimate rather than exact value and should be verified in practical tests for the individual application.

Kw [10-6 mm3/Nm]

· Kf · Kdyn · KT · K J,HRC · KJ,Ra · KJ,Mat

Correction factor load type Correction factor dynamic load Correction factor temperature Correction factor hardness Correction factor roughness Correction factor shaft material

Determining the specific bearing load Equation 3

p=

Equation 4

p=

F D·B 4·F π · (D02 - Di2)

Determining the sliding speed (bush, washer): Equation 5

U=

π·D·N 60 · 103

Equation 6

U=

π·D x 60 · 103

2 · ϕ · Nosc 360

Determining the nominal life expectancy for operation under alternating stress Determining the nominal life expectancy for operation under alternating stress tmax is calculated by classifying loads and sliding speeds in groups within which both sizes are approximately constant. tmaxi , the maximum life expectancy of each class, is calculated, and then factored with the frequency of occurrence. The total of factored individual results corresponds to the maximum life expectancy of the bearing.

Equation 7

16 • Saint-Gobain Performance Plastics

∑

tmax =

ti · tmax i tcycle

Calculation of life expectancy Example 1: Oscillating motion

Known data: Nominal bearing diameter

A bearing is to be manufactured with NORGLIDE® M. The shaft is made of hard steel (55 HRC) with a surface finish Ra=0,2µm. Required life expectancy: 1500 h. Load: uniform, in one direction.

Maximum permissible radial wear: 150 µm. To be determined is the maximum life expectancy

D

Nominal bearing width B Bearing load Slewing frequency Slewing angle Ambient temperature

F Nosc ϕ Tamb

12 mm 8 mm 1000 N 75 min- 1 60° 80 0C

The calculation of the specific bearing load p per equation 3 results in:

F D·B

p=

1000 12 · 8

p=

MPa

p = 10.42 MPa

The speed is calculated per equation 5:

U=

π·D x 60 · 103

2 · ϕ · Nosc 360

U=

π · 12 2 · 60 · 75 · m/s 60 · 103 360

U = 0.016 m/s

Now the pU value can be determined with equation 1:

pU = p · U

pU = 10.42 · 0.016 MPa · m/s

pU = 0.17 MPa · m/s

A verification of the p, U and pU values for suitability (graph A) demonstrates that they are within the recommended range.

The following values are determined as correction factors:

KJ,HRC = 1

(steel: 55 HRC)

Kf

=1

(lumped load)

KJ,Ra

(Ra= 0,2µm)

Kdyn = 1

(uniform load)

(steel)

KT

(temperature 30°C)

=1

KJ,Mat = 1

=1

The life expectancy can be determined with equation 2:

tmax =

hmax Kw · pU · 3.6

tmax =

150 0.18 · 0.17 · 3.6

· Kf · Kdyn · KT · K J,HRC · KJ,Ra · KJ,Mat ·1·1·1·1·1·1h

tmax = 1362 < tmax, required = 1500 h

By increasing the nominal width B (to 10 mm) p and pU can be reduced and hence the nominal life expectancy be increased.

p=

1000 MPa 12 · 10

p = 8.33 MPa

pU = 8.33 · 0.016 MPa · m/s tmax =

150 0.18 · 0.13 · 3.6

pU = 0.13 MPa · m/s

·1·1·1·1·1·1h

tmax = 1781 > tmax, required = 1500 h

The required life expectancy is exceeded. NOTE: pU = pV

17

Calculation of life expectancy Example 2: Rotary motion A bearing is to be manufactured with NORGLIDE® SM. The shaft is made of hard steel (55 HRC) with a surface finish Ra=0,2µm. Required life expectancy: 1000 h. Load: uniform, but rotary.

Maximum permissible radial wear: 250 µm.

Question: Is it possible to reduce the nominal bearing width?

The calculation of the specific baring load p per equation 3 results in:

F D·B

p=

p=

2000 MPa 25 · 15

p = 5.33 MPa

The speed is calculated per equation 5:

U=

π·D·N 60 · 103

U=

π · 25 · 31 m/s 60 · 103

U = 0.041 m/s

Now the pU value can be determined with equation 1:

pU = p · U

pU = 5.33 · 0.041 MPa · m/s

pU = 0.22 MPa · m/s

A verification of the p, U and pU values for suitability (graph A) demonstrates that they are within the recommended range.

The following values are determined as correction factors:

Known data: Nominal bearing diameter

D

25 mm

= 2 (peripheral load)

Kdyn = 1

Nominal bearing width B

15 mm

Bearing load

F

Slewing frequency

Nosc 31 min- 1

Ambient temperature

Kf KT

(uniform load)

= 0,7 (temperature 80°C)

KJ,HRC = 1

(steel: 55 HRC)

KJ,Ra

(Ra= 0,2µm)

=1

KJ,Mat = 1

(steel)

2000 N Calculation of life expectancy per equation 2:

0

Tamb 80 C tmax =

hmax Kw · pU · 3.6

tmax =

250 0.24 · 0.22 · 3.6

· Kf · Kdyn · KT · K J,HRC · KJ,Ra · KJ,Mat · 2 · 1 · 0.7 · 1 · 1 · 1 h

tmax = 1841 >> tmax, required = 1000 h

The nominal bearing width is related with the life expectancy so that a reduction by one third (to 10 mm) is possible.

p=

F D·B

pU = p · U

p=

2000 MPa 25 · 10

p = 8.00 MPa

pU = 8.00 · 0.041 MPa · m/s

pU = 0.33 MPa · m/s

A verification of p, U and pU values for suitability (graph A) demonstrates that they are within the recommended range.

tmax =

hmax Kw · pU · 3.6

tmax =

250 0.24 · 0.33 · 3.6

· Kf · Kdyn · KT · K J,HRC · KJ,Ra · KJ,Mat · 2 · 1 · 0.7 · 1 · 1 · 1 h

tmax = 1228 > tmax, required = 1000 h

The required life expectancy is reached.

The nominal bearing width can be reduced from 15 mm to 10 mm.

18 • Saint-Gobain Performance Plastics

Calculation data and units (ISO 7904) Nominal width of bearing (length)

B

[mm]

Nominal diameter of bearing

D

[mm]

Inside diameter of washer’s retaining ring

Di

[mm]

Outside diameter of washer’s retaining ring

D0

[mm]

Max. permissible radial wear

∆hmax [µm]

K-factor

Kw

[10-6mm3/Nm]

Bearing load

F

[N]

Rotational frequency

N

[min-1]

Slewing frequency

Nosc

[min-1]

Specific bearing load

p

[MPa]

pU value

pU

[MPa · m/s]

Wall thickness

s

[mm]

Ambient temperature

Tamb

[0C]

Max. life expectancy

tmax

[h]

Duration of approximately constant pU conditions within the load cycle

ti

[h]

Duration of load cycle

tcycle

[h]

Max. life expectancy at approximately constant pU conditions within the load cycle

tmaxi

[h]

Sliding speed

U

[m/s]

Slewing angle

ϕ

[°]

19

Design of the bearing The life expectancy of a bearing is very much dependent on its design where factors like load, dimensions, material selection, surface finish and geometry have to be taken into consideration.

In many cases the dimensions of a bearing are dictated by the design environment.

An estimate of the life expectancy can determine which NORGLIDE® type is capable of bearing a given load. If necessary, the pivot point has to be modified accordingly.

Requirements on the tribological properties and the knowledge of influences by the bearing environment help to select the proper NORGLIDE®material.

Practically, the mating or contact surface can be made of any steel or plastic. Better performance is achieved with surfaces in a hardness range of 50 to 60 HRC. The use of plastics is, therefore, limited to a few isolated cases, whereas the selection of metals focuses on various steel grades.

Another factor vitally important for the life expectancy of a bearing is the surface finish. Sharp elements in the surface – even if tiny – can never be avoided in machined parts. It is therefore recommended to choose drawn, rolled or milled surfaces.

Polished surfaces produce erosion damage and are not ideal contact surfaces. For slowly oscillating movements, the value of mean surface finish Ra should range between 0.15 - 0.80 µm, for high frequency oscillating and rotating movement, it should be in between 0.15 - 0.35µm. Corrosion alters the surface roughness appreciably and hence increases wear so that suitable protection methods or a corrosion-resistant steel should be used. In extremely dirty environments, the bearing should be protected with proper sealing systems.

Housings should have chamfers according to DIN 3547 to ease the installation of bearings. The pins or shafts should be designed with a radius to avoid damage to the bearing surface during installation.

20 • Saint-Gobain Performance Plastics

Tolerancing NORGLIDE® bearings are designed for either a heavy press fit into a housing or to be inserted by hand. Bearings designed for hand insertion are usually flanged bearings that require a secondary flange to retain the bearing in the housing.

See the “Installation of the bearings” section for more detail on this. The housing tolerance has a direct linear relationship to the mounted bearing ID tolerance. This tolerance can be reduced by sizing the ID of the bearing after installation. The “Sizing” section covers this capability in detail.

Clearance fits (between bearing and pin) The tolerance field on the inside diameter is controlled by the tolerance on the bore size and the tolerance of the NORGLIDE® bearing. With some material types the tolerances between pin and inside diameter of the bearing can be adapted by sizing (see page 22). This procedure allows producing a new bearing inside diameter with a closer tolerance range. Extremely tight clearance fits can be obtained by using adequately toleranced pins (min. h7). For rotary motions, linear sliding motions or high frequency oscillating motions the minimum clearance should not be less than 0.015 to 0.020 mm.

Interference fits (between bearing and pin) NORGLIDE® materials offer the opportunity to design clearance free bearings. For this purpose the combination of pin/NORGLIDE® bearing/housing is selected in a way that always interference is obtained. This interference is possible, because NORGLIDE® materials have an extraordinary thick PTFE layer which provides elasticity. When installed, this elasticity exercises back pressure onto the pin and hence produces a torque in slewing motions and isolates noise. Sizing and accurately toleranced pin diameters make it possible to limit the torque. After sizing the interference should not be more than 0.01 mm including consideration of wear.

21

Sizing What is sizing?

NORGLIDE® bearings are made of compo-

diameter of the installed bearing by up to

of sizing and has to be deducted when

site materials.The individual components

0.150 mm, depending on the length of the

designing the bearing, otherwise the

display a more or less developed plastic

pivot point and the material type.

secondary flange will be too large.

and elastic deformation capability. Plastic

NORGLIDE® materials with metal fabric

NORGLIDE® T is the only product with a

deformation is used for sizing, i.e. altering

or stretched metal are ideal for sizing. A

limited sizing capability.When sized, the

the sizes to a certain degree.The material

steel backing limits the sizing capability of

bearing material adapts to the surface of

can be formed by sizing with tools (usual-

longer bearings. NORGLIDE®-PRO types

the housing wall and hence reduces the

ly a sizing pin). By sizing the bearing in the

are also sizable due to the PTFE tape

tolerance range.

original housing, the overall tolerance

which is encapsulated in the polygon

range (tolerance of housing + tolerance of

structure. Sizing alters mainly the radial

bearing material) can be very much redu-

thickness of the bearing material. At the

ced.This allows for wider production tole-

same time the bearing increases in

rances and the associated cost benefits.

length. This increase in length depends

Sizing allows for an increase of the inside

on the NORGLIDE® type and the amount

Sizing for clearance-fit

Sizing for interference-fit

Design of sizing pins

In addition to the permanent deforma-

Depending on the NORGLIDE® material

The geometry of sizing pins is described

tion of the radial wall thickness of a

begin with an interference of 0.150 to

on page 24 Detail „Y“. For the purpose of

NORGLIDE® bearing, an elastic defor-

0.250 mm. After sizing, the maximum

this study, only the active sizing range of

mation is to be taken into considera-

interference on the pin to be mounted

a sizing pin will be examined in detail.

tion when sizing. Consequently, the in-

should not exceed 0.010 mm. This

To calculate the pin’s diameter deduct

side diameter resulting from a sizing

interference is important if, for

twice the largest NORGLIDE® thickness

step is always smaller than the diameter

instance, a torque is to be generated in

from the smallest housing size. Add the

of the sizing pin. Therefore, to ensure a

a hinge. The suitable modification of

value of 0.05 mm to this calculated bea-

permanent clearance fit between bea-

housing and/or pin allows to design

ring inside diameter to have the diame-

ring and pin, sizing beyond the target

any fit between clearance-fit and inter-

ter of the first sizing pin. Sizing should

is needed. After this, due to the plastic

ference-fit.

take place in maximum steps of 0.06

recovery of the sliding layer, the final

mm to prevent damage to the bearing

inside diameter is achieved.

surface. Each sizing step should be made in both directions to prevent delamination of the bearing layer. It is not recommended to combine several sizing steps with the aid of a multi-step mandrel.

22 • Saint-Gobain Performance Plastics

Continuous torque as a function of interference, exemplified by Norglide® MP (qualitative illustration) 1.6 1.4

Torque [Nm]

1.2 1.0 0.8 0.6 0.4 0.2 0.0 0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

0.11

0.12

Interference after sizing [mm]

Torques Torques are dictated by the coefficient of friction, pressure, friction surface, speed and finish of the rubbing-contact surfaces.

In contrast to the Coulomb law of friction, the coefficient of friction depends on both pressure and sliding speed. Therefore, no universal value can be given (see page 13).

For some applications, particular torques are specified. The material composition of NORGLIDE® MP, S, M, SM and SMTL is such that an interference fit between the pin and the bearing’s inside diameter (see page 21) is designed to produce torque.

The pressure depends on the pin’s interference with the inside diameter of the bearing. This pressure in the cylindrical (radial) part of the bearing produces the torque. With flanged bearings additional (axial) torque may be produced if pressure is exerted on the flanged surfaces. By appropriate changes in the design, such as proper adjustment of the riveting shoulder height, effects can be influenced in the axial direction. Another factor that influences total torque and should be considered in the design is the riveting process.

Only the torque produced in the radial part of the bearing will be examined in detail. The following test with NORGLIDE® MP may serve as an example: With a bearing length of 19.3 mm and a pin diameter of 8.00 mm the range of interference was varied between 0.02 mm and 0.08 mm. Torques in the range of 0.3 N to 1.4 N were reached.

Interferences > 0.08 mm should not be used to prevent damage to the bearing surface. Unevenly spread wear of the sliding layer may lead to an uncontrolled increase of the torque. Strong pre-stress may reduce the life expectancy of the bearing.

The following factors should be taken into account: • The torque values should not be too high.

• Due to the material’s recovery the torque increases after installation.

• When a bearing with high interference between the bearing’s inside diameter and the pin is exposed to temperatures > 200°C over a longer period, unstressing of the PTFE layer is noticed. The torque drops accordingly.

Due to the vast variety of parameters that influence torque, the values retained for the torque range should be verified in practical tests for the individual application.

23

Installation of NORGLIDE® bearings The process described below is somewhat idealized, but includes the most important steps for installing NORGLIDE® bearings into a housing. If and in which order the individual steps have to be made depends on the material type, the application and the technical feasibility and should be discussed with our application engineers.

How to feed the bearing to the installation point The degree of automation decides on whether the bearing is inserted by hand or by machine. With tangle-free bearings, a combination of vibration feeder and gripper can be used. Long distances between feeder and installation point are overcome by „shooting“ the bearing pneumatically through a profile tubing.

How to insert the bearing into the housing Bearings with a loose fit in the housing do not necessarily need a mandrel for installation. If a mandrel is used, calculate its diameter by deducting twice* the largest NORGLIDE® thickness from the smallest inside diameter of the housing; then deduct the value of 0.05 mm. (*takes three times the largest NORGLIDE thickness in the case of a MP bearing with overlap). Details of a mandrel design to accom-

Detail "X"

plish press fit of the bearing are shown in the drawing.

How to prevent movement of the bearing To prevent bearing movement during all subsequent forming operations, so-called “downholders“ are used which grip the axial flange and fix the bearing. A „dead stop“ (spacer) prevents squeezing of the flange (see Detail Z).

Pressing in

Sizing 75% Nominal bearing length

Detail "Y"

F

F

Downholder

Y Detail "Z"

Dead deadstop stop

24 • Saint-Gobain Performance Plastics

Chamfer

How to size the inside diameter The possibilities of modifying the bearing's inside diameter by sizing were discussed in detail on page 22. The sizing pin must have all transitions designed with radii as shown in Detail X. Its active sizing range must be hardened and polished. Additional tapering of the pin may ease lead-in.

How to form the 2nd flange in one or two steps Usually flanging is done in two steps: 1st step: 45°; 2nd step: 90°. In particular cases, if the geometry of housing and pin allows, the 2nd flange can be formed in a single step, but it will be narrower than a flange formed in two steps. This must be considered when designing the bearing. Also in this case all transitions must be designed with radii (Detail Z) and the active sizing range must be hardened and polished.

Additional tapering may ease lead-in. A „dead stop“ prevents squeezing of the 1st and of the 2nd flange (Detail XYZ).

Pre-flanging

Final flanging Downholder

Downholder

Z

X

R = Material thickness + 0.75

X

R = Material thickness + 0.5 25

Measuring NORGLIDE® bearings Drawings for NORGLIDE® fabricated parts do not only describe the dimensions of the bearing, but also state the measurement methods used.

Measuring NORGLIDE® bearings with steel backing

Measuring NORGLIDE® bearings without steel backing

This method for testing the outside diameter can be carried out on all bushings

This group of bearings is made of flexi-

suitable for NORGLIDE® bearings with steel backing > 0.5 mm and for all PRO types.

ble materials. A master gauge is used to

With the gap up, the bushing is inserted into the master gauge. Using a given test

make sure the measurements are re-

force the two shell halves are pressed together so that the bushing is exposed to a

producible and comparable. To perform

pre-stressing force in the elastic range. Determined is the deviation of distance z

the measurement, the NORGLIDE® bea-

(from a standard value) between the shell halves. The exact procedure and evalua-

ring is inserted into a ring gauge.

tion of this method - which is known also as ∆z test - is described in detail in ISO

A plug gauge descends into the bearing

3547-2.

The diameter measurement is performed on the basis of the methods described in standard ISO 3547-2. These are:

Test A per ISO 3547-2 that have an interference fit to the housing’s inside diameter. This means, it is only

and ensures it has a firm seating and optimum roundness. The gauge is flattened on one side and has one or two inspection windows. A gauge pin is used to determine the gap size X. The master gauge is designed to measure both the length of the bush and the maximum permissible flange diameter.

Test B per ISO 3547-2 This simplified method for testing the outside diameter can be carried out on all NORGLIDE® bushes with steel backing and on bearings with and without a flange regardless of the material thickness.

The test uses GO and NO GO ring gauges. The GO gauge must take up a NORGLIDE® bearing when pressed in by hand. The NO GO gauge must not accept the bearing when pressed in with the same force. The diameters of the gauges are selected according to standard 3547-1.

In this GO gauge, the flange diameter can be tested.

Test C per ISO 3547-2 This method is used for testing the inside diameter. It can be carried out on all NORGLIDE® bushings with steel backing and on bearings with and without a flange regardless of the material thickness.

The test uses a gauge. In this master gauge the inside diameter of the bearing can be tested with plug gauges. The GO plug gauge should fit with a minimum of force.

The NO GO plug gauge must not fit by hand. The fitting forces and diameters of these plug gauges have to be agreed upon with the user.

26 • Saint-Gobain Performance Plastics

Measurement gages for â&#x2C6;&#x2020;z

27

Corrosion resistance The NORGLIDE® bearing steel shell can be provided with an anti-corrosive coating combined of zinc plating, Cr6 free passivation and sealing, depending on what kind of protection is needed. In a few special cases, other corrosion-protection systems can be used to avoid contact corrosion. All systems comply with the European Union End-ofLife directive for automotive vehicles 2000/53/EG. In comparison with components of solid refined metal, specially structured NORGLIDE® bearings have a shorter corrosion resistance when exposed in the salt spray chamber.

The corrosion resistance of the individual components is not necessarily identical with the life expectancy of the assembly. For choosing the proper anti-corrosive coating, the composition and operating conditions should also be taken into account. Actual corrosion resistance should always be verified in the assembled condition.

Some NORGLIDE® types use a stainless steel backing and do not need additional corrosion protection. Some NORGLIDE® types use a backing of aluminum which also does not require further protection because it passivates itself. In both cases however the electro-chemical chain must be taken into account to prevent contact corrosion in the assembled condition.

Flexible NORGLIDE® variants are reinforced by mesh or stretched metal structures of tin/bronze CuSn6 (material No. CW452K), of stainless steel FeCr18Ni10Mo3 (material No. 1.4401), of aluminum AlMg3 (material No. 3.3536) and do not need additional corrosion protection. Also in this case the electro-chemical chain must be taken into account to prevent contact corrosion.

The resistance to red and white corrosion of NORGLIDE® bearings is tested to DIN EN ISO 9227 during production in our own salt spray chamber. In special cases the salt spray test is conducted on parts in the assembled condition.

28 • Saint-Gobain Performance Plastics

Salt Spray Chamber

29

Integrated Management Quality … we team with our customers: All quality related criteria of NORGLIDE® bearings are established with the customer in our NORGLIDE® drawing.

… we achieve certifications: Our modern quality management complies with international standards. Certificates are provided on request.

… we plan quality: With our quality preplanning systems we identify and plan all criteria and their risks - from the drawing board to delivery.

… we inspect and test quality: Alongside our reliable production processes and statistical process control techniques, our highly trained staff is responsible for a continuous improvement program in compliance with the Six Sigma philosophy.

EHS Environment, Health and Safety … we ensure compliance: While considering environmental protection as a key element our company is committed to maintaining health and safety, because health and motivation of our staff are the core of highly efficient performance.

… this means to our customers: We are, and will remain, an attractive, highly reliable partner for sustained success.

30 • Saint-Gobain Performance Plastics

Quality, Environment, Health and Safety (QEHS) Policy Future by sustainability In order to sustain our company's success •

We focus on the protection and the inviolacy of employees and environment and on complying with customers' requirements.

•

We accompany new developments with integrated QEHS concepts.

•

We pursue a zero-defect strategy in all departments.

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We take care of our products all the way from the technical concept to the start of production at our customers.

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We want to exceed our employees' and our customers' expectations.

In order to assure this sustainability •

We set QEHS and economic goals and evaluate achievement.

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We provide capable, controlled and reliable processes and procedures while steadily reducing the distribution (6σ).

We continuously improve our products, our processes and our management system.

We prevent defects and accidents by suitable programs.

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We strictly comply with the requirements made by customers, norms and laws.

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We have our management system certified and audited according to ISO/TS 16949, DIN EN ISO 14001 and OHSAS 18001.

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We involve our suppliers into our QEHS activities.

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In order to be able to achieve our goals •

We promote high-level qualification and a definite sense of responsibility of our employees by continuous training and education.

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We reduce environmental and health hazards for our employees by using modern technologies.

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We minimise our consumptions to preserve natural and corporate resources.

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We regularly check, monitor and evaluate the results of our activities.

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We work in interdisciplinary teams.

The Saint Gobain Performance Plastics Pampus GmbH management team

31

Practical Application

1

Door hinge

2

Seat adjustment systems

3

Two-mass fly wheel

4

Belt tensioner

5

Decoupled pulley

6

Steering gear

7

Pedal linkages

8

Light projection range adjustment

9

Shock absorber

10

Front hood hinge

11

Trunk hinge

12

Windshield wiper

13

Brake lever

14

Automatic mirror adjustment

15

Steering column adjustment

Two-mass fly wheel

11

9 10 12 13

15

14 3 5

1

4 7

6 8

32 â&#x20AC;˘ Saint-Gobain Performance Plastics

2

Flap hinges

Convertible systems Pedal linkages

Hinges Shock absorber

Belt tensioner Sliding door

33

Ball joint

Practical Application

Expansion groove

Door hinge

Seat mechanism

Pump

We thank the following companies for the photografic material provided:

Swivel drive

Valves

Bicycle brake

1

Front shock absorber

2

Rear shock absorber

3

Pivot points rear shock absorber

4

Pivot points rear shock absorber

AUMA Riester GmbH & Co. KG Campagnolo CR Hammerstein Dr. Hahn Edscha GAT Gesellschaft für Antriebstechnik mbH ISE Innomotive Systems Europe GmbH Kirchhoff GmbH & Co. KG Litens Metso Automation Maurer Söhne GmbH & Co.KG SRAM Trek ZF Sachs AG

3 2

4

34 • Saint-Gobain Performance Plastics

1

RA M EXT RU SIO N MA C & M HIN E CO OLDE D MP ON D EN TS

RU LON ®

ME LDI N®

OM NIS EAL ®

OM NIL IP™

NO RSL IDE ®

NO BEA RGLID RIN E® GS

I NJ E MO CTIO LDI N NG

EUROPE * Saint-Gobain Performance Plastics Pampus GmbH Willich · Germany

Phone: (49) 21 54 60 0 Fax: (49) 21 54 60 310

* Saint-Gobain Performance Plastics N.V. Kontich · Belgium

Phone: (32) 34 58 28 28 Fax: (32) 34 58 26 69

Saint-Gobain Performance Plastics Asti Nanterre · France

Phone: (33) 1490 70204 Fax: (33) 1490 69760

Saint-Gobain Performance Plastics Agrate Brianza (Mi) · Italy

Phone: (39) 03 96 50 070 Fax: (39) 03 96 52 736

Saint-Gobain Performance Plastics España, S.A. Barcelona · Spain

Phone: (34) 93 4948856 Fax: (34) 93 4948857

* Saint-Gobain Performance Plastics España, S.A. Logroño · Spain

Phone: (34) 94 14 86 035 Fax: (34) 94 14 37 095

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NORTH AMERICA Phone: (1) 973-696-4700 Fax: (1) 973-696-4056

* Saint-Gobain Performance Plastics Corporation Bristol, Rhode Island · USA

Phone: (1) 401-253-2000 Fax: (1) 401-253-1755

* Saint-Gobain Performance Plastics Corporation Garden Grove, California · USA

Phone: (1) 714-995-1818 Fax: (1) 714-688-2701

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SOUTH AMERICA * Saint-Gobain Cerâmicas & Plásticos Ltda.

Performance Plastics – Division Vinhedo-SP · Brazil

Phone: (55) 19 3876 -8193 Fax: (55) 19 3876 -8038

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ASIA * Saint-Gobain KK-Performance Plastics Tokyo · Japan

Phone: (81) 33 26 30 285 Fax: (81) 33 26 30 286

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* Saint-Gobain Performance Plastics Korea Co., Ltd. Seoul · South Korea

Phone: (82) 25 08 82 00 Fax: (82) 25 54 15 50

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* Saint-Gobain Performance Plastics (Shanghai) Co., Ltd. Phone: (86) 21 54 72 15 68 Fax: (86) 21 54 72 23 78 Shanghai · China

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* Saint-Gobain Advanced Materials (Taiwan) Co., Ltd. Taipei · Taiwan

Phone: (886) 22 50 34 201 Fax: (886) 22 50 34 202

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* Grindwell Norton Ltd. Bangalore · India

Phone: (91) 80 2847 2900 Fax: (91) 80 2847 2905

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Phone: (66)26405435 Fax: (66)26405439

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Saint-Gobain Performance Plastics Bangkok · Thailand * Manufacturing Facilities

NORGLIDE® · NORSLIDE® · RULON® · MELDIN® · OMNISEALS® · EKONOL® are registered trademarks.

Warranty: The data and information in this catalogue or in our web sites are not binding and were correct and up-to-date at the time of release. Technical modifications and developments as well as adaptations to comply with amended standards, norms and guidelines can be made without notice. The product characteristics, especially load bearing capability and wear, depend on the application and the environment the product is used in. Therefore the data does not assure specific product characte-ristics or make reference to the suitability of the product for a definite or fictitious application. In case of new applications users must test the product under these actual application conditions and the application should be discussed with the manufacturer. Within the scope of law any liability for us, and all those acting on our behalf, for the data and information in this catalogue or in our web sites shall be excluded. Any contracts are concluded on the basis of our General Business Terms and Conditions, which could be downloaded from our web site, or forwarded to you as requested.

www.norglide.com

35

BSTE-4154-3K-0508 © 2008 Saint-Gobain Performance Plastics Pampus GmbH · Am Nordkanal 37 · D-47877 Willich · Germany · Phone: +49 (0) 2154/60-0 · Fax: +49 (0) 2154/60-310

* Saint-Gobain Performance Plastics Corporation Wayne, New Jersey · USA