DIN 3869 Silicone Sealing Ring
Manufacturer & Custom Solutions
Profile Sealing Rings for Threaded Ports and Stud Ends
DIN 3869 profile sealing rings are used on hydraulic ports, stud ends and screw plugs. The standard material for these rings is NBR, and FKM for oil and heat resistance. Silicone is a better choice when the seal faces extreme temperatures, because it keeps its elasticity from -60°C to +200°C where NBR gets hard. It is also safe for food and medical equipment. ZSR makes all standard sizes in DIN 3869 and custom sizes on request. Send us your size list to get a factory price.
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 3869 Rings Are
DIN 3869 covers profiled elastomer sealing rings for threaded ports and stud ends — the fittings you find on hydraulic valves, pneumatic equipment, pumps, and tube connectors. You will also hear them called profile rings, D-rings, or ED-rings.
The shape is what makes them special. A DIN 3869 ring is a thick ring with a trapezoidal profile — narrower at the top, wider at the base. It sits in a counterbored port cavity and seals axially, squeezed between the fitting face and the port bottom when the thread is tightened.
Two things set these rings apart from ordinary seals:
This specific geometry is why the same profile has become the standard answer for high-pressure threaded sealing across the hydraulic world.
Profile Types and Dimensions
Standard dimensions (mm):
Nominal Size | Metric Thread | Inch Thread | ID (d1) | OD (d2) | Profile Height (T) |
|---|---|---|---|---|---|
8 | M8×1.0 | – | 6.5 | 9.9 | 1.0 |
10 | M10×1 | G 1/8 A | 8.4 | 11.9 | 1.0 |
12 | M12×1.5 | – | 9.8 | 14.4 | 1.5 |
14 | M14×1.5 | G 1/4 A | 11.6 | 16.5 | 1.5 |
16 | M16×1.5 | – | 13.8 | 18.9 | 1.5 |
17 | – | G 3/8 A | 14.7 | 18.9 | 1.5 |
18 | M18×1.5 | – | 15.7 | 20.9 | 1.5 |
20 | M20×1.5 | – | 17.8 | 22.9 | 1.5 |
21 | – | G 1/2 A | 18.5 | 23.9 | 1.5 |
22 | M22×1.5 | – | 19.6 | 24.3 | 1.5 |
27 | M26×1.5 / M27×2 | G 3/4 A | 23.9 | 29.2 | 1.5 |
33 | M33×2 | G 1 A | 29.7 | 35.7 | 2.0 |
42 | M42×2 | G 1¼ A | 38.8 | 45.8 | 2.0 |
48 | M48×2 | G 1½ A | 44.7 | 50.7 | 2.0 |
60 | M60×2 | G 2 A | 56.5 | 66.1 | 4.0 |
Profile accuracy is everything with this seal — the trapezoid angle and the two height steps (T and T1) control how the ring compresses. ZSR molds every DIN 3869 ring to the standard profile and checks the cross-section on optical measuring equipment. Send us your fitting drawing or an old ring, and we will match the profile exactly.
Material Selection for Hydraulic and Pneumatic Service
Service | Recommended Material | Why |
|---|---|---|
Low-pressure pneumatic systems | Solid silicone (VMQ) | Soft seal at low torque, -60°C to +200°C, never hardens like NBR in the cold |
Hydraulic oil contact | FVMQ (fluorosilicone) | Resists swelling in mineral oil and fuel — standard VMQ swells and fails here |
Hot hydraulic systems, engine compartments | High-temp silicone | Heat-stabilized for long service at 200°C+ |
Food and medical fluid equipment | FDA / USP Class VI silicone | Food-safe and body-safe sealing for hygienic hydraulics |
Explosive environments (ATEX zones) | Conductive silicone | Dissipates static charge — no spark risk at the fitting |
Two honest limits, so you buy the right ring:
What Is DIN 3869?
DIN 3869 is a German standard for elastomer profile sealing rings — the shaped rubber rings that seal threaded ports, stud ends, and screw plugs in hydraulic and pneumatic systems. Published by DIN, the German Institute for Standardization, it defines a trapezoidal ring profile and a complete size series from M8 to M60 (plus inch-thread equivalents), so that one ring shape seals reliably across an entire industry. Where an O-ring can twist and a flat washer can extrude, the DIN 3869 profile does neither — which is why it has become the default soft seal for threaded fluid connections worldwide.
Key Points of the Standard
At ZSR Silicone Parts, we mold silicone DIN 3869 rings in the full standard size range — and match custom profiles to your drawing or sample. Tell us your thread size and your fluid, and we will quote within 24 hours.