What an Elbow Hose Stud Does
An elbow hose stud is the removable end fitting that connects an 8.6 x 4 high-pressure grease hose to a lubrication point when the line must turn immediately at the port. The routing rule is simple: use a straight hose stud for straight-line exits, and use this 90 degree elbow when the hose would otherwise be forced into a tight bend at the fitting. A sharp bend there strains the reinforcement and shortens hose life; the elbow takes the turn in rigid steel instead. The stud is one part of a three-piece hose-end connection and can be reused if the threads and sealing surfaces are undamaged.
Technical Specifications
| Parameter | Value |
|---|---|
| Fits hose | 8.6 mm OD x 4.0 mm ID, +/-0.1 mm tolerance |
| Body material | Carbon steel S20C / S45C |
| Plating | Zinc 8-12 um, yellow chromate |
| Port threads | M7 x 0.75, M9 x 1; optional G1/8 BSPP or R1/8 BSPT |
| Working pressure | 350 bar (5,000 PSI) at 20°C |
| Proof pressure | 525 bar (7,500 PSI) |
| Temperature range | -40°C to +120°C |
| Hex size | 11 or 14 mm |
| Coupling system | Cutting-ring side per DIN 2353 / ISO 8434-1 |
The yellow chromate finish gives improved corrosion resistance for plant and mobile equipment. The fitting is dimensionally compatible with common centralized lubrication systems.
Thread Options and How to Identify
M7 x 0.75 is the common small-port thread on this hose size, while M9 x 1 appears on larger ports and manifolds. Where a pipe thread is needed, G1/8 BSPP parallel or R1/8 BSPT tapered versions can be supplied.
Confirm before ordering: measure the male major diameter with a caliper (about 7 mm for M7, 9 mm for M9), then check pitch with a thread pitch gauge (0.75 mm or 1.0 mm).
Routing and Installation
Plan the run so the elbow points the hose along its path without twisting it. The cutting-ring side follows the bite-type assembly of the DIN 2353 / ISO 8434-1 system:
- Check that the thread, cone, and cutting ring are clean and undamaged.
- Seat the stud and hand-tighten the nut until the ring grips.
- Tighten a further 1.5 turns (L series) on the 11 or 14 mm hex.
The barb side assembles into the hose:
- Lubricate the barb lightly with clean grease.
- Push the hose fully home over the barb until it seats on the shoulder.
- Position the ferrule over the barb section and clamp it evenly.
After assembly, bring the system up gradually and inspect each joint for weeping before running at full pressure. For broader routing practice, see the lubrication tubing and hose selection guide.
Working with the Hose and Ferrule
The elbow stud belongs to a matched set: it is sized for the 8.6 x 4 steel-braided high-pressure hose, and a compression ferrule closes over the barb to lock the hose in place. Before reusing the stud on an existing line, cut the hose back to sound material if the end is flattened or cracked.
What Is Supplied
Each unit is the 90 degree elbow hose stud in carbon steel with yellow zinc plating, in the thread option confirmed at order stage. Matching ferrules, nuts, and hose are available as companion items. Send your requirements through the quotation page to confirm thread, hex size, and hose pairing.
Frequently Asked Questions
Will this elbow stud fit my 8.6 x 4 hose?
Measure the hose with a caliper: outside diameter should read 8.6 mm and inside diameter 4.0 mm, within +/-0.1 mm.
How do I tell M7 x 0.75 from M9 x 1?
Measure the male thread’s major diameter – roughly 7 mm indicates M7, roughly 9 mm indicates M9 – then confirm pitch with a thread pitch gauge: 0.75 mm for M7, 1.0 mm for M9.
When is an elbow stud better than a straight stud?
Choose the elbow when the hose must turn immediately at the port, when a straight exit would side-load the hose end, or when wrench clearance behind the port is limited.
What does the three-part hose-end set include?
The hose stud (this elbow or its straight variant), a compression ferrule that clamps the hose over the barb, and the nut used on the coupling side – all matched to the 8.6 x 4 hose.
Can the cutting ring be reused?
A ring that has bitten correctly should stay on its tube or stud and not be moved to another assembly. If the bite looks skewed or uneven, replace the ring.
Should I check the assembly at pressure afterward?
Yes. Bring the system up gradually and inspect each new joint for weeping before running at full 350 bar working pressure.
Should I choose barb or cutting-ring assembly?
They serve different sides of the joint. The barb secures the flexible hose under the ferrule; the cutting-ring side follows the DIN 2353 / ISO 8434-1 bite-type method on the rigid connection.
Can this stud be used on pneumatic circuits?
Yes, but a 350 bar steel fitting is usually oversized for pneumatic duty. Low-pressure pneumatic lines commonly use brass fittings.
How do I ask about a stainless steel version?
Note the thread size, hose size, and the environment – washdown, outdoor, or corrosive – and include those details when you contact us so the material can be confirmed.
Who makes this stud and how do I get a quote?
This fitting is made by IsoHiTech Lubrication Systems, founded in 2023, engineering since 2006 in centralized lubrication components. Send hose size, thread, and quantity through the quotation page or write to inquiry@isohitech.com.
