DIN 2353 Fittings, i.e. DIN 2353 pipe fittings, are widely used non-welded pressure connection fittings in accordance with the standards set by the German Institute for Standardisation (Deutsches Institut für Normung, or DIN).
Dimensional drawing of hydraulic couplings according to DIN 2353：
| End Size | Thread | Drill | Tube Nut Assembled Allowance | Tube Depth | Male Turn Back | Bulkhead Length | Tube/Swive Nut Hex | Bulkhead Nut Hex | Max Bulkhead Thickness | |
| Size | D3 (mm) | M Metric | D (mm) | F (mm) | K (mm) | L1 (mm) | L3 (mm) | S2 (mm) | S4 (mm) | X (mm) |
| 4LL 6LL 8LL | 4 6 8 | M8x1 M10x1 M12x1 | 3 4.5 6 | 5.5 6 6 | 4.2 5.7 5.7 | 8 8 9 | 10 12 14 | |||
| 10LL 12LL | 10 12 | M14x1 M16x1 | 8 10 | 6 6 | 5.7 6.2 | 9 9 | 17 19 | |||
| 6L | M12x1.5 | 4 | 8 | 7.2 | 10 | 34 | 14 | 17 | 16 | |
| 8L | 8 | M14x1.5 | 6 | 8 | 7.2 | 10 | 34 | 17 | 19 | 16 |
| 10L | 10 | M16x1.5 | 8 | 8 | 7.2 | 11 | 35 | 19 | 22 | 16 |
| 12L | 12 | M18x1.5 | 10 | 8 | 7.2 | 11 | 36 | 22 | 24 | 16 |
| 15L | 15 | M22x1.5 | 12 | 8 | 7.2 | 12 | 38 | 27 | 30 | 16 |
| 18L | 18 | M26x1.5 | 15 | 9 | 7.7 | 12 | 40 | 32 | 36 | 16 |
| 22L | 22 | M30x2 | 19 | 9 | 7.7 | 14 | 42 | 36 | 41 | 16 |
| 28L | 28 | M36x2 | 24 | 9 | 7.7 | 14 | 43 | 41 | 46 | 16 |
| 35L | 35 | M45x2 | 30 | 11 | 10.7 | 16 | 47 | 50 | 55 | 16 |
| 42L | 42 | M52x2 | 36 | 12 | 11.2 | 16 | 47 | 60 | 65 | 16 |
| 6S 8S 10S | 6 8 10 | M14x1.5 M16x1.5 M18x1.5 | 4 5 7 | 8 8 9 | 7.2 7.2 7.7 | 12 12 12 | 36 36 37 | 17 19 22 | 19 22 24 | 16 16 16 |
| 12S | 12 | M20x1.5 | 8 | 9 | 7.7 | 12 | 38 | 24 | 27 | 16 |
| 14S | 14 | M22x1.5 | 10 | 10 | 8.2 | 14 | 40 | 27 | 30 | 16 |
| 16S | 16 | M24x1.5 | 12 | 10 | 8.7 | 14 | 41 | 30 | 32 | 16 |
| 20S 25S 30S | 20 25 30 | M30x2 M36x2 M42x2 | 16 20 25 | 11 12 13 | 10.7 12.2 13.7 | 16 18 20 | 44 47 51 | 36 46 50 | 41 46 50 | 16 16 16 |
| 38S | 38 | M52x2 | 32 | 15 | 16.2 | 22 | 53 | 60 | 65 | 16 |
| Note:For port and studend dimensions reference section F:Pipe Fittings and Port Adapters. | ||||||||||
Definition and standard:
Definition: DIN 2353 Fittings are occlusal fittings, primarily used for pipe connections in fluid power systems, which do not require O-rings or other elastomers to form a leak-proof seal.
Standard: The fittings comply with DIN 2353, which specifies the design, dimensions and technical requirements for compression fittings and coupling assemblies to ensure reliability and leak-free performance of the fittings.
Features and benefits:
Leak-free performance: DIN 2353 Fittings provide leak-free connections through a unique occlusal mechanism that ensures efficient fluid transfer and system reliability.
High pressure tolerance: Some models of DIN 2353 Fittings can be used in application scenarios up to 800 bar (S-Series) and 500 bar (L-Series).
High corrosion resistance: Stainless steel fittings with a Cr(VI)-free surface treatment are resistant to white rust corrosion for more than 500 hours, extending the life cycle of the fittings.
Easy to install: Although installation requires some technical and equipment support, once properly installed, it ensures consistent, leak-free performance over the long term
Material and application:
Material: DIN 2353 pipe fittings are usually made of stainless steel and carbon steel, with stainless steel fittings dominating at 59% and carbon steel fittings at 24%.
Application: The product is mainly used in industrial applications and engineering machinery, with a share of 47% and 27% respectively. In addition, it is also widely used in various industries such as automotive, defence, energy, environment, infrastructure, machine tools, material handling, oil and gas, and power generation.
