Garlock GYLON Style 3545 PTFE Gasket Sheet

Name: Garlock GYLON Style 3545 PTFE Gasket Sheet – Datasheet & Quote
Brand: Garlock
SKU: Style 3545

Soft-faced PTFE sheet with a rigid core for low bolt loads

GYLON Style 3545 has highly compressible microcellular PTFE outer layers over a rigid PTFE core. Garlock says the soft layers seal under low bolt load and conform to irregularities, especially on warped, pitted or scratched flanges, while the core reduces cold flow and creep.

Garlock also notes that the rigid core makes installation easier on large-diameter flanges and in hard-to-reach places, and that gaskets can be cut from larger sheets, reducing inventory cost and downtime. Media named are strong caustics, strong acids, hydrocarbons, chlorine and cryogenics, plus glass-lined equipment and low bolt load applications.

Technical specifications

Parameter	Specification
Manufacturer / style	Garlock, GYLON Style 3545
Composition	Microcellular PTFE with rigid PTFE core
Colour	White
Fluid services	Strong caustics, strong acids, chlorine, hydrocarbons, cryogenics, glass-lined equipment and low bolt load applications
Temperature, minimum / ideal operating limit / maximum	-450 °F (-268 °C) / 400 °F (204 °C) / 500 °F (260 °C)
Pressure, minimum / ideal operating limit / maximum	Full vacuum / 750 psig (52 bar) / 1200 psig (83 bar)
P x T maximum	350,000 psig x °F (12,000 bar x °C) for 1/32 and 1/16 in; 250,000 (8,600) for 1/8 in
Specifications printed	ABS; FDA 21 CFR 177.1550; will not support flame or bacterial growth
Compressibility, ASTM F36	60 to 70 %
Recovery, ASTM F36	15 %
Creep relaxation, ASTM F38	15 %
Design factors, ASTM F586 (m; y)	1/16 in and under: m 2.6, y 1500 psi (10.3 N/mm2); 1/8 in: m 2.0, y 2200 psi (15.2 N/mm2)
Gasket constants, ROTT	1/16 in: Gb 162.1, a 0.379, Gs 1.35×10-9; 1/8 in: Gb 92.48, a 0.468, Gs 2.50×10-3; 3/16 in: Gb 628, a 0.249, Gs 7.93×10-5
Sealing characteristics	ASTM F37B Fuel A at 1000 psi (7 N/mm2) gasket load and 9.8 psig (0.7 bar): 0.15 ml/hr; DIN 3535 nitrogen at 4640 psi (32 N/mm2) and 580 psig (40 bar): less than 0.015 cc/min
Catalogue example on garlock.com	0.094 in x 60 x 60 in sheet (2.4 x 1524 x 1524 mm), white, branded

Values are the typical properties printed in the Garlock spec sheet (August 2023). Garlock marks them as a general guide.

When a low-load PTFE gasket is the right answer

With compressibility of 60 to 70 % and a y factor of only 1500 psi (10.3 N/mm2) up to 1/16 in, this is the sheet to consider where flanges cannot be tightened hard, such as FRP, plastic-lined or glass-lined pipework and large flanges with limited bolting. Recovery is just 15 %, so the gasket behaves more like a conformable cushion than an elastic spring.

Footnote 2 on the datasheet adds a condition: for flat-face flanges a minimum compressive stress of 1500 psi (103 N/mm2) on the contacted area is recommended for 150 psig (10.4 bar) liquid service, and the flange maker should confirm that the stress is available. The Garlock listing for this style also carries a technical bulletin on HDPE flange gaskets for flange adapters and stub-end connections.

Related Garlock gasket sheets

Other low-load and conforming options from Garlock are compared below.

Garlock style	Composition	Colour	Media and use printed by Garlock
GYLON Style 3565 ENVELON	PTFE with aluminosilicate microspheres (ENVELON)	White exterior, blue interior	Moderate acids and caustics, hydrocarbons, glass-lined equipment
GYLON Style 3504	PTFE with aluminosilicate microspheres	Blue	Many acids, some caustics, hydrocarbons, solvents, hydrogen peroxide, refrigerants, cryogenics
GYLON EPIX Style 3504 EPX	PTFE with aluminosilicate microspheres, hex profile	Blue	One thickness does the job of two; same material as traditional GYLON 3504
GYLON Style 3510	PTFE with barium sulfate	Off-white	Strong caustics, moderate acids, chlorine, gases, steam, hydrocarbons, cryogenics

Documents, ordering details and quotation

Tell us the flange material and facing, and the bolt load you can apply. For a quotation please give the medium and concentration, design and test pressure, temperature, the flange standard and facing, bolting, the thickness and whether you need whole sheet or gaskets cut to size. Garlock describes its datasheet as a general guide that should not be the sole means of selecting or rejecting a material, so confirm the grade with Garlock Applications Engineering for any critical duty. More products are listed under gaskets, seals and pipe fittings.

GYLON and BLUE-GARD gasket sheets

The sheets listed here come from two families. GYLON is the PTFE based range for chemical, food and pharmaceutical duties, and BLUE-GARD is the aramid fibre range for water, oils, steam and gases. Each official spec sheet shows the style, service limits, typical properties and the approvals that are printed on it.

Seven Star LLC links the manufacturer document on every product page, so buyers can verify the figures and approvals themselves before they send an inquiry.

Choosing the right style

The correct style depends on the medium and concentration, temperature, pressure, flange facing and bolt load. Send these details with your request for quotation and we compare them with the published Garlock data before we quote, referring critical duties back to the manufacturer. Sheets can be quoted as whole sheets or as gaskets cut to size.

Frequently Asked Questions