Suspended PTFE

(Suspended PTFE for Molding )
In general
Suspended PTFE for molding has two types : Suspended Fine Grain ( PTFE 7C ) and Suspended middle grain ( PTFE 7A ) .

PTFE granular molding powders are ideal for molding many different products and stock shapes , such as rods, tubes and sheets . products fabricated from PTFE stock shapes are unaffected by nearly all chemicals and feature superior electrical properties . These products , some of which are rated for continuous service at 260 C ( 500 F ) , also provide exceptional low-temperature toughness , plus unique adhesion and flame resistance .

Processing : PTFE granular molding powders are processed by preparing a pre-form , sintering the pre-form , and then fabricating functioning machined parts form the sintered stock shape . Filled compounds are easily produced from this PTFE granular powder by mixing 5% to 60% , by weight , of inorganic fillers that selectively enhance properties .

Pre-forming: Adequate pre-form pressure are required to maximize end-use performance. Typical pressure range from 3,000 to 4,500 psi with dwell times varying with pre-form size . Stock shapes pre-formed at lower pressures exhibit inferior physical properties ( Specific density , tensile strength , elongation , flex life ) , electrical properties , and permeation and chemical resistance .

Sintering : Adequate sintering requires a programmable oven . The temperature is slowly raised from room temperature to 363 to 382 C ( 685 to 720 F 0 . Hold times at these temperatures vary with part geometry and dimensions . The oven temperature is then slowly lowered to room temperature . Stock shapes that are not properly sintered exhibit inferior physical properties (( Specific density , tensile strength , elongation , flex life ) , electrical properties , and permeation and chemical resistance
Packaging and Transportation
Packed in double layer PVC bags inside and in hard circular barrels outside . On the barrel , we attached label and quality certificate , lot no , net weight , etc .

It is transported as non-hazardous material , Heat , moisture , freezing and strong shock shall be avoided during transportation because over-bumpiness and compression is apt to make the resin bind together.
Suspended Fine Grain ( PTFE 7C )

 

Items

Unit

PTFE  7C1

PTFE  7C2

 

Grade 1

Grade 2

Grade 1

Grade 2

1

 

Smooth & Clean

 

White sheet surface , even quality , no foreign matter .

Even Sheet quality .

Total residue &Spots: 6 Max

Reside ( 0.5-2 mm ): 2 Max

Spot ( 2-3 mm )    : 1 Max

2

Tensile strength

 

MPa

29.0 Min

27.4 Min

29.0 Min

27.4 Min

3

Extension at break

%

300 Min

280 Min

300 Min

280 Min

4

Bulk density

 

g/L

 

300 C 450

5

Residue on sive ( 65 um )

%

um

 

15% Max

6

Moisture

 

%

0.04% Mx

7

Melting point

 

C

 

327+/- 5 C

8

Standard relative density

 

2.13 C 2.19

9

Thermal instability index 

 

2 Max

10

Electrical strength

MV/m

100 Min

80 Min

 

Applications
Suspended Fine Grain , PTFE 7C , is widely used in field of skived film and sheet , gaskets, bridge or pipeline bearing pads , piston rings, and diaphragms .
Suspended Middle Grain ( PTFE 7A )

 

Items

Unit

PTFE  7A1

PTFE  7A2

 

Grade 1

Grade 2

Grade 1

Grade 2

1

 

 

Smooth & Clean

 

Clean & White surface , even quality , no foreign matters . Diameter =57 mm , no color difference for rod cross section

Clean & white surface , even quality , no metal residue , .

 

Residue (1mm Max) : 2 Max

2

Tensile strength

MPa

27.0 Min

25.5

3

Extension at break

%

250

4

Volume density

g/L

500 +/- 100

5

Average Particle size

um

180 +/- 80

6

Moisture

%

0.04 Max

7

Melting point

 

C

 

327+/- 5 C

8

Standard relative density

 

2.13 C 2.18

9

Thermal instability index 

 

20 Max

10

Electrical strength

Mv/m

60 Min

 

Applications
Suspended Middle Grain , PTFE 7A , is widely used in field of skived film and sheet , gaskets, bridge or pipeline bearing pads , shaft bearings , electrical insulators , piston rings, expansion bellows , diaphragms, and chemical linings .



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