Material Expertise

A comparison to the conventional PTFE gasketing production process shows the difference. PTFE – PolyTetraFluoroEthylene – is an unbranched, linear, semi-crystalline polymer of fluorine and carbon. Due to its chemical inertness, PTFE is used as a coating where aggressive chemicals occur in industry. Virgin PTFE has many advantages. Some of them are exceptional chemical resistance, wide temperature range, lowest friction coefficient, low surface energy, non-stick surface properties, no embrittlement of aging and excellent electrical and dielectrical properties. But it also has several disadvantages. It is very soft and has the tendency to cold flow. PTFE is also called “dead” material because, when compressed, it remains in this state. It is also fragile and surfaces must be smooth and hard. GYLON® offers a good possibility to use the advantages of PTFE, but due to its production process to eliminate the typical disadvantages – and even to improve the material. GYLON® is a modified and restructured PTFE.



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GYLON BIO-PRO® PLUS: Cleanability Test

According EHEDG guideline No. 2 in order to compare material cleanability


Test Results

In order to assess the cleanability of the gaskets after the simulated cleaning procedure according to EHEDG guideline 2, they were tested for residual microorganisms. The evidence was provided by a color change of the nutrient medium from violet to yellow. This color change is caused by the pH indicator Bromocresol purple in the presence of acid-forming microorganisms. The material GYLON® Style 3522 repeatedly showed only good cleaning results. Only if the contaminants are able to grow in the special nutrient media used, it will show yellow coloring during the detection procedure. The acid formation of the test organism during the growth phase (by-product of cell growth) causes the corresponding color change (violet to yellow) of the nutrient medium.


The EPDM 1 gasket showed no yellow coloring in the tests, which according to EHEDG means that the gasket is free of contamination. However, further investigations using fluorescence microscopy have shown that the EPDM 1 gasket was completely covered with contaminants. It was therefore concluded that the EPDM 1 gasket had antimicrobial properties which led to a failure of the test procedure and a false positive result. In comparison GYLON BIO-PRO® PLUS showed no yellow coloring in the test and in the fluorescence microscopy only few contaminants.

The material GYLON® Style 3522 repeatedly showed only good cleaning results.

Results test for residual microorganism

Fluorescence Microscopy Pictures

CIP & SIP Cleaning

The media in the production cycle as well as the cleaning cycle must be safely sealed. The cleaning processes are carried out using CIP (Clean-In-Place) as well as SIP (Sterilization-In-Place). The CIP process is a cleaning method in which individual fully automated processes run according to strictly specified parameters. The cleaning temperatures are determined according to the application and are usually around 90°C. The CIP process is followed, as a possible extension, by sterilization using the SIP process. Here, in automated processes, active microorganisms are killed at around 140°C using hot water or steam, depending on the application. The use of chemical disinfectants is also possible during this process.

GYLON BIO-PRO® PLUS: Intrusion Test

Compare the intrusion inside the Tri-Clamp after mechanical and thermal stress

The gaskets were installed with the Tri-Clamp connections and the clamps screwed to the respective torques (PTFE gaskets with 5 Nm and elastomer gaskets with 3 Nm). In order to determine the intrusion behavior of the gaskets, the inner diameters of the gaskets were measured at six points each:

1. measurement of the inner diameter before assembly
2. measurement of the inside diameter after installation at room temperature
3. measurement of the inner diameter after exposure to heat in assembled conditions

Standard Tri-Clamp Connection

Test Results

The values given in Figure below represent the differences of the measured inner diameters:

Bar 1 (Color1): Difference between the original inner diameter of the gasket and the inner diameter of the gasket after assembly.
Bar 2 (Color 2): Difference between the inner diameter of the gasket after assembly and the inner diameter of the gasket after heat exposure in the assembled condition.
Bar 3 (Color 3): Measured total intrusion of gaskets = intrusionassembly + intrusionheat exposure.

PTFE GASKETS: Before-After with 5 Nm Torque

ELASTOMERS (70° Shore A): Before-After with 3 Nm Torque

The results have shown that GYLON BIO-PRO® PLUS has a comparatively very low intrusion behavior. In particular, the elastomer gaskets and the PTFE/elastomer gaskets show relatively high intrusion behavior, both after assembly at room temperature and again after exposure to heat.

Engineered gasket design – Decreased dead space

Elastomeric Gasket

  • ID intrusion
  • Product accumulation
  • Bacterial build-up

Traditional PTFE

  • ID recession
  • Product accumulation
  • Bacterial build-up


  • Smooth bore
  • Easy cleaning
  • Dimensional stability

GYLON® Certificates/Declarations

In order to meet the requirements of your special applications, we have subjected our materials to special tests. Detailed records on the tests listed below are available upon request.

(Please click on the table to enlarge)

Additional certificates for individual styles are available upon request (i.e. ABS, EC10/2011, USP class 87, Hydrocheck).

Style 3522

  • 3-A (Sanitary Standard)
  • FDA 21 CFR177.1550
  • NSF 61 Standard
  • EC1935/2004 incl. EC10/2011
  • USP Class VI <87>, <88>
  • USP <31>,<281>,<661>
  • 62. BfR
  • Phthalate free
  • Silicone free
  • ADI free (EMEA 410/01)
  • TA – Luft incl. blow-out proof

Experts & Services

The Garlock family of GYLON® products has evolved over the years with a focus on quality to meet and exceed customer expectations. The use of Employee Involvement, Statistical Process Control, Vendor Assurance Programs, and a continuous improvement philosophy continues to guarantee end users the highest quality products available. Testing is performed regularly on all styles and thicknesses to ensure the consistency of Garlock quality in GYLON® sheets. Quality products, years of experience and value-added service programs, all are reasons why the GYLON® family of products has become such a major sealing component in the industry today.

Our experts are application engineers as well as sales engineers. All are highly trained and can discuss and debate the requirements of your applications with you professionally and expertly and advise you on the way to the best fitting sealing solution.


How to find us

Garlock GmbH
Falkenweg 1
41468 Neuss


+49 2131 349-0


Garlock Global Website


Career Site Europe

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