Standard Flange Silicone Gaskets
Manufacturer & Custom Solutions
Standard Flange Silicone Gaskets
Standard flange silicone gaskets from ZSR Silicone fit ANSI, DIN and JIS pipe flanges. We cut them to your bolt pattern and inner diameter for a perfect fit. Materials range from commercial VMQ to FDA and high-temperature grades.
FDA 21 CFR 177.2600
Rubber Articles Intended for Repeated Use
LFGB 30&31
EU Food Contact Materials
USP Class VI / ISO 10993
Biocompatibility of Medical Devices
RoHS / REACH
Environmental Compliance
UL 94
Flammability of Plastic Materials
Built to Your Exact Spec
Custom Silicone Gaskets Options
| Image | Product | Type | Short Info | Action |
|---|---|---|---|---|
 | DIN 32676 Silicone Gasket | Standard & Size | DIN 32676 tri-clamp silicone gaskets, FDA food grade, full size range in stock at ZSR factory. | View Details |
 | AS568 Standard Silicone Gaskets | Standard & Size | AS568 standard-size silicone gaskets for groove-based sealing applications. | View Details |
 | DIN 3869 Silicone Sealing Ring | Standard & Size | DIN 3869 profile sealing rings in silicone for hydraulic ports, working from -60°C to +200°C. | View Details |
 | EN 1514-1 Silicone Gasket | Standard & Size | EN 1514-1 silicone flat gaskets for PN flanges, IBC and FF types, standard and custom sizes. | View Details |
 | Custom Die Cut Silicone Gaskets | Standard & Size | Flat silicone gaskets cut to any shape from sheet stock. Precision cutting for exact fits. | View Details |
 | ISO 7483 Silicone Gasket | Standard & Size | Silicone gaskets to ISO 7483 for ISO 7005 flanges, made for international projects and tenders. | View Details |
 | Custom Molded Silicone Gaskets | Standard & Size | Three-dimensional silicone gaskets made by compression or injection molding. For complex sealing shapes. | View Details |
 | ISO 1127 Silicone Gasket | Standard & Size | Sanitary silicone gaskets matched to ISO 1127 stainless steel tube sizes for food and pharma lines. | View Details |
 | Standard Flange Silicone Gaskets | Standard & Size | Silicone gaskets cut to fit pipe flanges. Matches ANSI, DIN and JIS bolt patterns. | View Details |
 | B16.21 Silicone Gasket | Standard & Size | ZSR makes silicone gaskets to ASME B16.21, ring type and full face type, for Class 150 to 2500 pipe flanges. | View Details |
 | ISO 2852 Silicone Gasket | Standard & Size | ISO 2852 silicone clamp gaskets for food industry couplings, FDA grade, factory direct from ZSR. | View Details |
 | Tri-Clamp / Sanitary Silicone Gaskets | Standard & Size | Hygienic silicone gaskets for food and pharmaceutical pipe connections. CIP and SIP compatible. | View Details |
 | B16.5 Silicone Gasket | Standard & Size | Silicone gaskets from ZSR sized to fit ASME B16.5 flanges, NPS 1/2 to 24 inch, Class 150 to 2500. | View Details |
 | Metric Size Silicone Gaskets | Standard & Size | Metric dimension silicone gaskets for international equipment standards. | View Details |
 | DIN 7603 Silicone Sealing Ring | Standard & Size | Flat silicone sealing rings made to DIN 7603 for screw plugs, banjo bolts and threaded fittings. | View Details |
 | DIN 2690 Silicone Gasket | Standard & Size | Silicone flat gaskets to DIN 2690 / EN 1514-1 dimensions for PN6 to PN40 flanges, food grade available. | View Details |
 | DIN 2691 Silicone Gasket | Standard & Size | Silicone gaskets made to DIN 2691 for tongue and groove flanges PN10 to PN160, ideal for plant repair. | View Details |
 | DIN 11851 Silicone Gasket | Standard & Size | Food grade silicone gaskets for DIN 11851 sanitary unions, DN10 to DN150, FDA material. | View Details |
 | FDA Food Grade Silicone Gasket | Grade | Food-safe silicone gaskets for processing equipment. FDA-compliant and taste-neutral. | View Details |
 | Medical Grade Silicone Gasket | Grade | Biocompatible silicone gaskets for medical devices. Sterilizable with full documentation. | View Details |
 | Industrial Grade Silicone Gasket | Grade | General-purpose silicone gaskets for industrial sealing. Reliable, durable and cost-effective. | View Details |
 | High Temperature / Heat Resistant Silicone Gaskets | Special Function | Heat-resistant silicone gaskets rated for continuous use above 200°C. For ovens and furnaces. | View Details |
 | Flame Retardant Silicone Gaskets | Special Function | Self-extinguishing silicone gaskets meeting UL 94 V-0. For fire-safety applications. | View Details |
 | Solid Silicone Rubber Gaskets | Materials | Solid silicone rubber gaskets with excellent compression set resistance and long service life. | View Details |
 | Fluorosilicone (FVMQ) Gaskets | Materials | Fuel and solvent-resistant silicone gaskets for chemical processing and automotive applications. | View Details |
 | Transparent / Clear Silicone Gaskets | Color | Clear silicone gaskets for visible sealing and light-transmitting applications. | View Details |
 | Black / White Silicone Gaskets | Color | Standard black and white silicone gaskets. Fastest delivery from stock. | View Details |
Full Face vs. Ring Type (IBC) Gaskets
Standard flange gaskets come in two basic shapes. Both seal flanges, but they fit different flange faces and different jobs:
Factor | Full Face Gasket | Ring Type (IBC) Gasket |
|---|---|---|
Shape | Covers the whole flange face, with bolt holes | A simple ring, sits inside the bolt circle, no bolt holes |
Flange Face Type | Flat Face (FF) flanges | Raised Face (RF) flanges |
Bolt Holes | Yes — bolts pass through the gasket | No |
Installation | Easy to position — the bolts hold it in place | Must be centered by hand |
Sealing Load | Spread over the full face | Focused on a smaller area, higher sealing stress |
Best Pressure | Low to medium pressure | Medium to higher pressure |
Extra Benefit | Protects the flange face; stops brittle flanges (like cast iron or plastic) from bending or cracking when bolts are tightened | Uses less material, lower cost on large sizes |
How to choose
Look at your flange. If the sealing face is flat all the way to the bolt holes, you need a full face gasket. If your flange has a raised face, a ring type (IBC) gasket is the right choice — the bolts sit outside the gasket, and the bolt load presses on a smaller area for a tighter seal.
Not sure which face type you have? Send us a photo of your flange, and we will confirm it for you.
Flange Standards We Cover
We cut silicone flange gaskets to all major international flange standards. The three main systems are not interchangeable — their bolt circles and sizes are different — so always tell us which standard your flange follows:
Standard System | Common Standard | Size Range | Rating System |
|---|---|---|---|
American | ASME B16.5 | NPS 1/2" – 24" (DN15 – DN600) | Class 150 / 300 / 600 |
American, Large Size | ASME B16.47 Series A / B | NPS 26" – 60" (DN650 – DN1500) | Class 150 / 300 |
European | EN 1092-1 (old DIN 2501) | DN10 – DN1200 | PN6 / PN10 / PN16 / PN25 / PN40 |
Japanese | JIS B2220 | 10A – 1500A | 5K / 10K / 16K / 20K |
For American standard flanges, our gasket sizes follow ASME B16.21 — the standard for non-metallic flat gaskets used with ASME B16.5 flanges.
Sample size data — ASME B16.5 Class 150, Ring Type (IBC) gaskets:
Pipe Size (NPS) | Gasket ID × OD (mm) |
|---|---|
1/2" | 21 × 48 |
1" | 33 × 67 |
2" | 60 × 105 |
3" | 89 × 137 |
4" | 114 × 175 |
6" | 168 × 222 |
8" | 219 × 279 |
10" | 273 × 340 |
12" | 324 × 410 |
Full dimension charts for all sizes, classes, and standards are available on request. If your flange is old, non-standard, or from a mixed system, send us the OD, ID, PCD, bolt hole size, and bolt hole number — we will make a custom gasket to fit.
What Is a Standard Flange Silicone Gasket?
A standard flange silicone gasket is a flat sealing ring made to fit standard pipe flanges — such as ASME B16.5, EN 1092-1, or JIS B2220 flanges. It sits between two flange faces. When the bolts are tightened, the soft silicone fills the small gaps and marks on the flange faces and stops leaks.
"Standard" means the gasket size follows a published flange standard. The pipe size, pressure class, outside diameter, bolt circle, and bolt holes are all fixed by the standard — so the gasket fits your flange right away, with no measuring and no custom drawing needed. You simply tell us the standard, the pipe size, and the pressure class, and we know exactly what to make.
We make these gaskets from silicone rubber for a good reason. Silicone seals at low bolt force, so it will not damage plastic, glass-lined, or light-duty flanges. It works from -60°C to over 200°C, much wider than EPDM or NBR rubber. It does not age in sunlight or ozone, and food grade silicone is safe for drinking water and food process lines. That makes silicone flange gaskets a smart choice for water treatment, food and beverage plants, chemical dosing lines, HVAC systems, and any hot or outdoor pipeline.
One honest note: silicone is a soft gasket material. It is best for low and medium pressure service — typically Class 150 and Class 300 flanges. For very high pressure steam or oil lines, a metal or spiral wound gasket is the right tool, and we will tell you so.
At ZSR Silicone Parts, we keep standard size data for ASME, EN/DIN, and JIS flanges on file, and we cut every gasket in our own factory. Common sizes ship fast. Tell us your flange standard and size — we will send a quote within 24 hours.