Rubber Gaskets — Custom Cut, Sheet Stock & Flange Seals

Custom cut, sheet stock and flange seals in EPDM, NBR, silicone, neoprene, FKM and PTFE. Flat static gaskets for bolt-loaded joints, delivered from drawing.

A rubber gasket is a flat elastomer or PTFE seal compressed between two mating surfaces to block fluid or gas leakage. Unlike an O-ring, which sits in a machined groove and relies on circumferential compression, a flat rubber gasket seals across its entire face under bolt load. This makes gaskets the default choice for flanges, manways, equipment covers, and sheet-metal enclosures where cutting a groove is impractical or uneconomical. We supply rubber gaskets as die-cut parts, waterjet-cut prototypes, CNC flashcut profiles, and sheet or roll stock for in-house fabrication. Common thicknesses range from 1/32 in (0.8 mm) to 1/4 in (6.4 mm), with 1/16 in and 1/8 in being the most requested for industrial flanges. Materials cover the same elastomer families we use for O-rings — NBR for oil and fuel, EPDM for water and steam, VMQ silicone for food and high temperature, CR neoprene for weather and refrigeration, FKM for chemicals and heat, and PTFE for aggressive media. A rubber gasket seal works by distributing bolt preload across the full face of a flat elastomer or PTFE element, creating a continuous barrier against leakage paths. Because the seal area is large and the geometry is simple, rubber gasket seals tolerate modest flange bow, surface scratches and out-of-flatness better than precision groove seals — provided bolt torque is applied in a star pattern and re-torqued after thermal cycling. Typical static pressure ratings for flat rubber gaskets fall between 20 and 50 bar, depending on material hardness, flange stiffness, bolt preload, and surface finish. The seal is created by controlled compression — usually 15–30% of gasket thickness — distributed evenly around the bolt pattern. Reuse is not recommended: once compressed, the gasket takes a set and will not recover enough to seal reliably on reassembly. Use our material selector grid below to narrow the right rubber gasket material, or request a quote with your drawing in DXF, PDF or STEP format.

Rubber Gasket Types

Sheet & Roll Stock

Uncut rubber gasket material supplied in sheets or rolls for fabrication shops and MRO teams. Standard widths 1.0–1.5 m, thicknesses 0.8–6.4 mm.

Best for: In-house die-cutting, prototype panels, large quantity blanket orders

Flange Gaskets

Full-face and inner-bolt-circle (IBC) ring gaskets cut to match pipe flange bolt patterns. ASME B16.21-style dimensions available.

Best for: Pipe flanges, pump housings, valve bonnets, tank manways

Ring Gaskets

Flat circular gaskets with a central hole, used on equipment covers, manways and clean-out ports. Custom ID, OD and thickness.

Best for: Manway covers, inspection hatches, filter housings

Custom Cut Gaskets

Any 2D profile from drawing — die-cut for volume, waterjet for prototypes, flashcut for medium runs without hard tooling.

Best for: Prototype to production, complex profiles, low-to-medium volume

Rubber Gasket Material Selector

EPDM

Ethylene Propylene Diene Monomer

−50°C to +150°C; excellent water, steam, ozone and UV resistance; not for petroleum oils

Best for: Water treatment, HVAC, outdoor enclosures, steam

NBR

Nitrile / Buna-N

−40°C to +120°C; oil, fuel and hydraulic fluid resistance; 70–90 Shore A typical

Best for: Hydraulic manifolds, fuel flanges, oil pans, industrial oil systems

Silicone (VMQ)

Vinyl Methyl Silicone

−60°C to +200°C; FDA and USP Class VI grades available; poor petroleum resistance

Best for: Food equipment, medical devices, high-temp static flanges

Neoprene (CR)

Chloroprene Rubber

−40°C to +120°C; ozone, UV and refrigerant resistance; moderate oil resistance

Best for: Marine, refrigeration, HVAC, outdoor cabinet doors

FKM (Viton)

Fluoroelastomer

−20°C to +200°C; high temperature, aggressive fuels and broad chemical resistance

Best for: Chemical processing, hot oil, automotive fuel flanges

PTFE

Polytetrafluoroethylene

−200°C to +260°C; universal chemical resistance; no elastic recovery — needs 20–25% compression

Best for: Aggressive chemicals, high purity, cryogenic static joints

Rubber Gasket Material Comparison

Indicative ranges for flat gasket service. Verify specific compound with your fluid and temperature.

Material	Temp Range	Shore A	Best Media	Relative Cost	Common Forms
EPDM	−50°C to +150°C	40–90	Water, steam, glycol	$	Sheet, ring, full-face
NBR	−40°C to +120°C	70–90	Oil, fuel, hydraulic fluid	$	Sheet, ring, die-cut
VMQ Silicone	−60°C to +200°C	30–80	Food, pharma, dry heat	$$	Sheet, FDA ring, red/orange
CR Neoprene	−40°C to +120°C	40–80	Refrigerant, ozone, marine	$$	Sheet, ring, outdoor strip
FKM Viton	−20°C to +200°C	65–90	Chemicals, hot oil, aggressive fuel	$$$$	Sheet, ring, high-temp flange
PTFE	−200°C to +260°C	55–65 Shore D	Universal chemical	$$$	Sheet, envelope, filled

Request a Custom Rubber Gasket Quote

Upload your drawing and specify ID, OD, thickness, material, hardness, quantity and application. We reply within 24 hours with die-cut, waterjet or flashcut options.

Request Quote Material Selection Guide

Frequently Asked Questions

What is a rubber gasket and how is it different from an O-ring?

A rubber gasket is a flat seal compressed between two flat mating surfaces under bolt load. An O-ring is a toroidal seal that sits in a machined groove and seals by radial or axial compression in a gland. Gaskets work without grooves; O-rings require groove geometry. See our [O-ring vs gasket comparison](/blog/o-ring-vs-gasket-vs-seal/) for a detailed breakdown.

Which rubber gasket material should I choose?

Start with the fluid and temperature. EPDM for water, steam and outdoor exposure. NBR for oil, fuel and hydraulic fluid. VMQ silicone for food, medical and high-temperature static service. CR neoprene for weather, ozone and refrigeration. FKM for aggressive chemicals and high heat. PTFE for universal chemical resistance where elasticity is not required.

Can I order custom rubber gaskets from a drawing?

Yes. Upload DXF, PDF or STEP files and specify material, hardness, thickness and quantity. We produce prototypes by waterjet or flashcut and scale to die-cut production for higher volumes.

What thicknesses are standard for flat rubber gaskets?

Common thicknesses are 1/32 in (0.8 mm), 1/16 in (1.6 mm), 3/32 in (2.4 mm), 1/8 in (3.2 mm), 3/16 in (4.8 mm) and 1/4 in (6.4 mm). Thinner gaskets need higher bolt preload for the same compression; thicker gaskets tolerate more flange unevenness but require more bolt travel.

How much compression does a rubber gasket need?

Most flat elastomer gaskets seal at 15–30% compression of the original thickness. Too little compression leaks; too much accelerates permanent set and can over-stress bolts. Flange stiffness and bolt torque must be designed to maintain this compression at operating temperature.

Are rubber gaskets reusable?

No. Flat gaskets take permanent set after the first compression cycle. Reusing a compressed gasket almost always results in reduced sealing force and leakage. Replace the gasket at every disassembly.

What surface finish is needed for a rubber gasket flange?

Typical sealing faces for flat rubber gaskets need Ra 1.6–6.3 µm (63–250 µin). Very smooth surfaces are unnecessary; rough or scored surfaces create leak paths. Full-face gaskets are more forgiving than narrow IBC rings because the sealing area is larger.

Do you supply rubber gasket sheet stock?

Yes. We stock sheet and roll stock in NBR, EPDM, neoprene, silicone and PTFE for customers who cut their own gaskets. Standard sheet sizes and roll widths are available; tell us your required thickness and durometer.

What is the pressure rating of a flat rubber gasket?

Most flat rubber gaskets handle 20–50 bar static pressure when properly bolted and constrained. Higher pressures require harder compounds, smaller extrusion gaps, backup rings or a switch to metal-reinforced or PTFE-envelope designs.