DIN 7603 Silicone Sealing Ring
Manufacturer & Custom Solutions
Sealing Rings (Dichtringe)
ZSR makes flat sealing rings to DIN 7603 dimensions. These rings are used on screw plugs, drain plugs, banjo bolts and threaded pipe fittings. The traditional material for this standard is copper, aluminum or vulcanized fiber. Silicone is a better choice when you need soft sealing at low torque, electrical insulation or food grade material. Our silicone rings work from -60°C to +200°C, do not corrode, and can be used again and again. We produce any inside diameter, outside diameter and thickness from your drawing or sample. Small orders are welcome.
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 |
What DIN 7603 Rings Are
DIN 7603 is a German standard for sealing rings used on threaded fittings and screw plugs — drain plugs, filler caps, banjo bolts, and threaded connectors. One thing to be clear about: these rings are not pipe flange gaskets. They are small washers that sit under a screw head or plug and seal the joint when the thread is tightened.
The typical shape is simple: a flat, washer-like ring with a precise inner diameter (to match the thread), an outer diameter (to cover the sealing face), and a defined thickness. Profiled versions with shaped cross-sections also exist for special fittings.
Sizes are named by the thread they fit. Common metric thread sizes include M6, M8, M10, M12, M14, M16, M18, M20, M22, M24, M27, M30, and up to M48 and larger pipe thread sizes. The traditional materials are copper, aluminum, and vulcanized fiber — silicone sealing rings follow the same standard dimensions, so they drop straight into any joint designed for a DIN 7603 ring.
Profile Types and Dimensions
The standard defines two ring constructions:
Common DIN 7603 sizes (Form A style, mm):
Thread Size | ID × OD × Thickness | Thread Size | ID × OD × Thickness |
|---|---|---|---|
M6 | 6 × 10 × 1 | M18 | 18 × 22 × 1.5 |
M8 | 8 × 12 × 1 | M20 | 20 × 24 × 1.5 |
M10 | 10 × 14 × 1 | M22 | 22 × 27 × 1.5 |
M12 | 12 × 16 × 1.5 | M24 | 24 × 29 × 2 |
M12 | 12 × 18 × 1.5 | M27 | 27 × 32 × 2 |
M14 | 14 × 18 × 1.5 | M30 | 30 × 36 × 2 |
M14 | 14 × 20 × 1.5 | M33 | 33 × 39 × 2 |
M16 | 16 × 20 × 1.5 | M42 | 42 × 49 × 2 |
M16 | 16 × 22 × 1.5 | M48 | 48 × 55 × 2 |
Many thread sizes come with more than one standard OD — check your fitting's counterbore, or just send us the old ring as a sample.
How we make them
ZSR molds or die-cuts DIN 7603 rings from solid silicone for general service, silicone sponge for soft, low-torque sealing, and FVMQ when the ring will touch oil or fuel. Food grade compounds are available for all three.
Applications and Material Selection
DIN 7603 silicone rings seal the small threaded joints that keep fluids where they belong:
Which material for which job:
Application | Recommended Material | Why |
|---|---|---|
General sealing — air, water, coolant | Solid silicone | Soft seal at low torque, reusable, -60°C to +200°C |
Oil and fuel contact — drain plugs, sumps | FVMQ (fluorosilicone) | Resists swelling in oil, fuel, and grease |
Engine compartments and hot zones | High-temp silicone | Heat-stabilized for long service near engines |
Fragile fittings, low bolt torque | Silicone sponge | Seals with very little force, protects soft housings |
One honest limit
Silicone rings are made for low and medium pressure threaded joints. For high-pressure hydraulic ports, a metal-backed or bonded seal is the right choice — ask us and we will tell you straight.
What Is DIN 7603?
DIN 7603 is a sealing ring standard from DIN, the German Institute for Standardization. Its German name is Dichtringe — simply "sealing rings." The standard covers the small flat rings used on threaded pipe fittings and screw plugs: it matches each ring size to a thread size, and fixes the inner diameter, outer diameter, and thickness so that any DIN 7603 ring fits any fitting made for it. It is one of those quiet standards that industry runs on — mechanics, engineers, and buyers across Europe and beyond order "a DIN 7603 ring" and know exactly what will arrive.
Key Points of the Standard
At ZSR Silicone Parts, we keep cutting tools and molds for the common DIN 7603 sizes, and we make custom dimensions from your drawing or an old sample. Small orders are welcome — tell us your thread size and your fluid, and we will quote within 24 hours.