20511C Metric Female 24-Degree Multiseal HEAVY-Series Hydraulic Hose Fittings (Swivel Nut)

Metric female 24-degree cone hydraulic hose fittings are the swivel-nut end for connections onto DIN/ISO 24-degree cone male studs in the heavy (S) thread schedule: the female nut turns freely on the hose tail, so you tighten onto the cone without twisting the hose. The 20511C multiseal series covers 9 part numbers from DN6 (-04) to DN32 (-20), with female metric threads from M18x1.5 to M52x2 that map to DIN heavy-series tube sizes from 10 to 38 mm, designed for wire-braided hose. If your machine connects hoses onto 24-degree cone male studs on the heavy thread schedule – the ports your 10511-type male fittings screw into – this page gives you the full reference: dimensions, part numbers, the T nut question and OEM options.

Why Choose These 24-Degree Cone Female Fittings

• The matching end for 24-degree cone male studs. The 24-degree cone seat seals metal-to-metal onto male studs in the ISO 8434-1 / DIN cone system – the female companion to heavy-series cone males such as the 10511 family.
• Heavy-series (S) thread schedule. Threads follow the DIN heavy schedule, M18x1.5 for a 10 mm tube class up to M52x2 for 38 mm, matching the machine ports of heavy-series drawings.
• Swivel nut that turns freely. The nut rotates on the hose tail, so the connection tightens without winding the hose or fighting the assembly position.
• OEM-ready. Laser marking, custom plating, material test reports and batch traceability, with both nut retention constructions available.

Standards and traceability. Threads are ISO 724 metric threads. The sealing geometry follows the 24-degree cone heavy series per ISO 8434-1 / DIN 3861, the successor system to the well-known DIN 2353 heavy (S) series. Fittings are designed to pair with wire-braided hose built to EN 853 1SN/2SN or SAE 100 R1AT/R2AT performance classes. Dimensional inspection reports and material test certificates are available for OEM gate checks.

Which Male Stud Does This Female Fit?

The female end must match the sealing geometry and the thread schedule of the male stud it connects to. This 20511C series fits a male stud with a 24-degree cone in the heavy (S) thread schedule – the same cone family as the 10511 and 10513 male series, and the DIN cone system used across European-specified and Chinese machines.

Two checks before you order: the cone angle must be 24 degrees, and the thread must be the heavy schedule (for example M30x2 for a 20 mm tube class). A heavy-series female will not thread onto a light-series male of the same nominal line, and a 60-degree cone or flat-face male takes its own series. When in doubt, send a photo of the male stud and the old female end, and we will confirm the correct family and schedule the same day.

What does multiseal mean on this series?

The catalog names this construction multiseal, and the Chinese sheet describes the sealing seat as spherical (球面). In practice the 24-degree cone seat seals metal-to-metal against the matching male cone, giving a reliable cone joint without a separate seal element. The exact seat geometry follows the manufacturer drawing; we will confirm the profile against your male stud if your application needs it.

20511C vs 20511C-T: the nut retention question

The sheet shows two ways of retaining the swivel nut on the hose tail: the standard construction (20511C) and the -T construction (20511C-T), which uses a different nut retention method shown on the drawing. The dimension table lists the -T construction for all nine sizes. Order the exact part number – with or without T – as printed on your drawing or the old fitting, and we will confirm the construction before dispatch.

The swivel nut, briefly

Like the other female swivel series, the nut rotates on the hose tail. You hold the hose where you routed it and turn only the nut onto the cone stud. No hose twisting, no re-routing after tightening, and the cone seal seats cleanly without side load.

20511C Series Technical Specifications

Materials and processing

• Body material options: high-strength carbon steel (20#/35#/45# grades, cold-formed or machined) as standard; stainless steel 304 or 316L available for corrosive or wash-down environments.
• Surface treatment: zinc plating as standard; yellow, white or black zinc, zinc-nickel and Dacromet coating available for higher salt-spray requirements.
• Heat treatment: hardness and case depth are controlled per drawing to keep the thread, the cone seat and the nut fatigue-resistant under heavy-service duty; typical surface hardness range HRC 20-28 (confirm the exact code on your drawing or PO).

Full dimension and part number table

All linear dimensions are in millimeters. E = thread, DN = hose bore, Tube O.D. = the DIN heavy-series tube size sharing this thread and cone geometry, A and C = lengths per the supplier drawing, S2 = swivel nut hex across flats. All listed rows use the -T nut retention construction per the drawing.

Full dimensioned CAD drawings are available on request so your engineers can verify every length, the cone seat and the nut retention construction before you commit a batch.

Working pressure: the honest answer engineers need

A crimp hose assembly fails at its weakest link, so the rating of a 20511C fitting depends on the hose you pair it with and the crimp quality. The heavy-series thread envelope is designed for higher-pressure duty, and wire-braided 2SN hose in this size range typically operates between roughly 80 and 400 bar depending on bore size. Send us your hose specification and we will confirm the working pressure, burst margin and the recommended ferrule for your exact hose brand – the check is free and takes one message. For derating at elevated temperature, follow the hose manufacturer’s pressure-temperature curve, because the rubber cover and tube lose capacity above about +100°C.

Which Fitting Series Do You Need: 20511C (Braided) or 20512C (Spiral)?

The part number changes with the hose construction, because the barb geometry and the crimp parameters are different.

When in doubt, check the hose label: braided hose is marked 1SN, 2SN or R1AT, R2AT; spiral hose is marked 4SP, 4SH or similar.

Part Number Decoder and How to Order

The 20511C part number carries the whole specification, so purchasing can copy it straight into a PO:

20511C – 30 – 10T

• 20511C = 24-degree cone heavy-series multiseal female for braided hose
• 30 = thread nominal size (here M30x2, DIN heavy-series class for 20 mm tube)
• 10 = hose dash size (here DN16, 5/8-inch class bore)
• T = nut retention construction per the drawing (all listed rows are T)

Because one thread size can serve several hose bores, always quote both the thread size and the dash size. If you are replacing an existing fitting, send us a photo of the nut end, the hose side and the male cone stud it connects to, and we will confirm the matching part number the same day. This service is the fastest way to convert an unreadable old part number into a confirmed 20511C order – and it also confirms whether your connection is 24-degree cone heavy, light, or another family.

Assembly Guide: Four Steps to a Reliable Crimp

These fittings are crimp-style hose ends with a swivel nut on the port end. Follow the four steps below on every assembly.

Étape 1 – Coupez le tuyau à angle droit. Use a sharp hose cutter or cutoff saw. A square, clean cut lets the ferrule grip the cover evenly. A beveled or ragged cut is the most common cause of pull-out failures.

Step 2 – Prepare the insert depth. Push the fitting tail into the hose until it bottoms firmly against the internal shoulder. The hose end must sit at the full insertion depth, not short, or the crimp zone will be wrong.

Étape 3 – Lubrifiez et insérez. Apply a thin film of assembly lubricant to the hose bore and the barb. Push the fitting in with a steady twisting motion until it bottoms out, then wipe away excess lubricant. Keep the 24-degree cone seat clean.

Étape 4 – Sertir et vérifier. Crimp the matched ferrule with the hose manufacturer’s crimp specification. After crimping, always measure the crimp outside diameter with a caliper and compare it with the crimp table. The measured value must sit inside the allowed tolerance band. If it is out of tolerance, do not put the assembly into service – cut it off and re-crimp with a corrected setting.

Warnings: three mistakes that cause leaks and blow-outs

• Never mix seal families. A 24-degree cone female must go onto a 24-degree cone male; 60-degree cone and flat-face males take their own series.
• Never mix heavy and light thread schedules. A heavy-series female will not thread onto a light-series male of the same nominal line.
• Never put PTFE tape or sealant on the thread, and never force the swivel nut when the cone is not aligned – clean seating needs a straight approach.

Typical Applications

The heavy-series 24-degree cone is one of the most widely specified metric cone systems in the world, so the 20511C female appears wherever hoses connect onto DIN-cone male studs on the heavy schedule:

• Hose assemblies onto pump, valve and cylinder ports with 24-degree cone male studs
• European-specified hydraulic systems and their global service networks
• High-pressure power units, presses and machine tools
• Plastic injection and die-casting machinery
• Mining, tunneling and construction equipment
• Marine and offshore auxiliary systems

Wherever the mating stud carries a 24-degree cone in the heavy-series thread schedule, the 20511C series is the female hose end – with the swivel nut keeping your routing exactly where you set it.

OEM Customization and Quality Traceability

For equipment builders and large maintenance programs, the 20511C series can be adapted to your exact drawing and your traceability rules.

Customization options

• Thread and geometry: special threads, modified lengths and non-standard configurations machined to your drawing or to a sample.
• Surface treatment: zinc-nickel, Dacromet or other coatings for higher salt-spray grades; we confirm the achieved test hours for the coating you choose instead of quoting a generic number.
• Laser marking: your logo, part number and batch or date code laser-marked on the nut or hex for full field traceability.
• Material: stainless steel 304/316L versions for corrosive media or wash-down duty.
• Nut retention: standard (20511C) or -T construction per your drawing or preference.
• Packaging and kitting: custom labels, barcodes, poly-bag or box quantities, and complete hose assembly kitting.

Quality documentation

• Batch number traceability: every order carries a batch code that links back to the production records.
• Material test reports (MTR) available for carbon steel and stainless batches.
• Dimensional inspection reports for OEM gate checks.
• Third-party inspection (BV, SGS or similar) can be arranged before shipment.

Samples and MOQ. Samples for stock sizes ship fast, and we keep low MOQs for standard part numbers so distributors can test the series without tying up capital. OEM programs can move to scheduled deliveries once the drawing is approved.

Emballage et logistique

Standard export packing: fittings are individually poly-bagged or boxed to protect threads, cone seats and swivel nuts, then packed in export cartons labeled with part number, quantity and batch code. Custom labeling, kitting and barcode requirements are available. Exact carton quantity, gross weight and CBM are confirmed on the packing list for every order.

FAQ

Q: What is a metric female 24-degree cone hydraulic hose fitting? A: It is a crimp-style hose end with a female metric thread and a 24-degree cone sealing seat, fitted with a swivel nut that turns freely on the hose tail. It connects onto a male stud with a 24-degree cone in the DIN/ISO cone system.

Q: What does the C and multiseal mean in 20511C? A: C marks this catalog construction, named multiseal in the series title; the Chinese sheet describes the sealing seat as spherical. In practice the 24-degree cone seat seals metal-to-metal onto the matching male cone. The exact seat profile follows the manufacturer drawing.

Q: What is the difference between heavy and light series in 24-degree cone females? A: The thread schedule. Heavy series uses larger threads for the same nominal line (for example M30x2 for a 20 mm tube class). The 20511C is the heavy-series female; light-series male studs take a light-series female.

Q: What is the difference between 20511C and 20511C-T? A: The -T version uses a different nut retention construction, shown on the manufacturer drawing. The dimension table lists the -T construction for all nine sizes. Order the exact part number your drawing specifies.

Q: What is the difference between 20511C and 20512C? A: 20511C is for wire-braided hose (1SN/2SN or R1AT/R2AT) and 20512C is for spiral hose (4SP/4SH style).

Q: Which male stud does this fitting connect to? A: A male stud with a 24-degree cone in the heavy (S) thread schedule – the same cone family as the 10511-type male fittings. It is not designed for 60-degree cone or flat-face males.

Q: Do I need thread tape or sealant? A: No. The 24-degree cone seals metal-to-metal. Tape on a straight metric thread adds nothing and can contaminate the system.

Q: What is the working pressure of these fittings? A: The assembly rating depends on the hose, the ferrule and the crimp quality. The heavy-series envelope is designed for higher-pressure duty. Send your hose specification and we will confirm the working pressure and the recommended ferrule for your combination.

Q: Can you make custom part numbers with my logo? A: Yes. We offer laser marking, custom plating, stainless versions and special dimensions, with MTR and batch traceability for OEM programs.

Order Today: 24-Degree Cone Female Fittings with Confirmed Fit

Every 20511C metric female 24-degree cone hydraulic hose fitting in this range is made to controlled dimensions, inspected before packing and backed by batch traceability. Send us your hose type, thread size and a photo of the male cone stud it connects to, and you will get a confirmed part number, the right nut construction, a delivery date and a quote within one working day. Request samples first and test the swivel on your own bench – turning the nut onto the cone instead of twisting the hose is the fastest way to feel the difference. We make sure the fitting, ferrule and hose work as one leak-free assembly.