Motion & Linkage

Stainless Steel Ball Joint Linkage

Q: How To Lubricate Ball Joints?

Clean the Zerk FittingUse a rag to wipe all dirt, crusty grease, and road grime off the Zerk fitting.Attach the Grease GunPush the grease gun coupler onto the Zerk fitting. You should feel it “snap” or lock into place. If it feels loose, the grease might squirt out the sides instead of going inside.Pump the GreaseSlowly pump the handle, stop as soon as you see the boot begin to swell or “fatten up.”Clean UpPull the coupler off, wipe away any excess grease from the fitting and the boot.

Profab Machine is a trusted manufacturer and supplier of stainless steel ball joint linkage. Our ball joint linkage are engineered with premium-grade stainless steel sourced from certified suppliers. They ensure long-lasting performance and corrosion resistance in even the harshest environments. Whether you need smooth motion, high load capacity, or long service life, our products are built to deliver.

What is Stainless Steel Ball Joint?

Stainless Steel Ball Joint is a kind of mechanical joint that allows multi-angle rotation and swing movement between two connected parts. A stainless-steel ball joint includes: ball, housing, liner, ball joint boot, and retaining. It mainly plays the role of supporting and transmitting power, and through the elastic connection, it can absorb vibration and reduce shock.

Product Range

Types of Stainless Steel Ball Transfer Units

Stainless steel ball joint linkages come in models like QD, ES, QI, CS. These models feature various ball socket types and sizes, providing flexible, durable connections for multiple industries. Profab offers comprehensive customization services. Our SS ball joints can be customized in terms of surface treatment, material, and packaging.

QD Series

Design	Quick Release with Spring
Stud	Thread Stud
Thread	Left / Right Hand
Material	304 / 316/ 440C (Optional 316 / 17-4PH)
Surface	Custom Finishing Available
Size	10-32, 1/4-28, 5/16-24, 3/8-24, 1/2-20, Custom

ES Series

Design	Staked with Rubber
Stud	Thread Stud
Thread	Left / Right Hand
Material	304 / 316/ 440C (Optional 316 / 17-4PH)
Surface	Custom Finishing Available
Size	10-32, 1/4-28, 5/16-24, 3/8-24, 7/16-20,1/2-20, 5/8-18, Custom

QI Series

Design	Quick Connection with Spring
Stud	Thread Stud
Thread	Left / Right Hand
Material	304 / 316/ 440C (Optional 316 / 17-4PH)
Surface	Custom Finishing Available
Size	10-32, 1/4-28, 5/16-24, 3/8-24, 1/2-20, Custom

CS Series

Design	Metric Ball Joint Linkage
Stud	Thread Stud (Sealing Cap Optional)
Thread	Left / Right Hand
Material	304 / 316/ 440C (Optional 316 / 17-4PH)
Surface	Custom Finishing Available
Size	M5, M6, M8, M10, M12, M14, M16, Custom

Swivel Ball Joint

Angle Ball Joints

Rod End Ball Joint

Axial Ball Joints

Selection Guide

Which Model Is Right for Your Application?

Requirement	Recommended Model
Frequent tool-free disconnection needed	QD (Quick Release)
Outdoor / marine / dusty environment	ES (Rubber-Sealed)
DIN 71802 metric compliance required	QI (DIN standard form)
Pin-through clevis connection	CS (Fork / Clevis)
Food zone, CIP washdown	QI + sealing cap, 316L
High-cycle automotive / motorsport	QD or CS in 17-4PH
Salt spray / marine corrosion	Any series in 316L
Aerospace, extreme strength	CS or QD in 17-4PH H900

* Not sure which model fits your assembly? Describe the load direction, disconnect frequency, and environment in the quote form — we will recommend the right series.

Safety Catch Clip — When to Specify

Per DIN 71802, ball joints are available with or without a safety catch clip. Without clip: swivel angle ±18°, ball can be disconnected by pulling beyond the snap-ring retention force. With clip: swivel angle limited to ±15°, but retention force is greatly increased and the ball cannot disengage under vibration. Always specify the safety catch for applications subject to vibration, shock loads, or reverse loading where unintended disconnection would be a safety risk.

Left-Hand Thread — When and Why

Left-hand (LH) thread ball joints are used in turnbuckle-style assemblies where one end must unthread as the other tightens, allowing length adjustment without disconnecting either end. They are also used in right-hand rotation systems where vibration would loosen a standard RH thread. All four series are available in LH thread. Specify at time of order — same pricing and lead time as RH.

Material Specification

Choosing the Right Grade

304 Stainless

Standard grade for indoor machinery, automation, and dry or mildly humid environments. Good resistance to cleaning chemicals. Cost-effective for high-volume orders. Not suitable for continuous salt spray or chloride-heavy process environments.

Food · Automation · Indoor

316 / 316L

Marine and food-grade standard. 2–3% molybdenum addition raises chloride pitting resistance significantly above 304. Required for outdoor, marine, offshore, and food equipment with CIP chemical cleaning. Especially 316 stainless steel has excellent resistance to corrosive saltwater effects.

Marine · Chemical · Pumps

17-4PH

Precipitation-hardened martensitic grade. ≥ 1,310 MPa tensile strength in H900 condition — significantly stronger than 316 at equivalent cross-section. Specified for ball joints in motorsport, aerospace, and high-cycle fatigue applications where load ratings are the primary constraint.

Aerospace · Motorsport · Hi-load

Applications

Diverse Applications of Stainless Steel Ball Joints

High-load design, exceptional corrosion resistance, and smooth low-friction movement — engineered to reduce mechanical failures and extend equipment life across industries.

Automotive & Motorsport

High-load design handles automotive suspension and steering impacts. Resists road salt, mud, and harsh underbody environments. Dynamic impact resistance without corrosion that accelerates on zinc-plated steel joints.

Marine & Offshore

316L construction provides exceptional corrosion resistance for marine hatch hinges, steering linkages, and deck machinery. Self-lubricating ball movement reduces maintenance in sealed marine assemblies.

Industrial Robots & Automation

Smooth, low-friction movement for industrial robot joints, pneumatic gripper linkages, and end-effector pivots. 440C ball resists fretting wear in high-cycle robotic applications. Profab works directly with brands to create integrated linkage systems.

Aerospace & Defence

Dust-proof sealing for secure aerospace control surface connections and actuator linkages. 17-4PH option provides the tensile strength required for structural linkage at reduced weight. Documentation meets aerospace requirements.

Solar & Renewable Energy

Resilience to extreme heat and cold for solar tracking systems and panel tilt mechanisms. Operating range –40°C to +200°C handles outdoor temperature cycles. Stainless outperforms galvanised alternatives in UV and weather exposure.

Medical Equipment

High-precision tolerances for fine-angle adjustments in medical imaging arms and surgical tables. Mirror-polished 316L meets hygienic surface requirements. Electropolished finish reduces bacterial adhesion in sterilisation-critical environments.

Why Profab

Your Reliable Ball Joint Supplier

Hardened Surfaces & Wear Engineering

Our stainless steel ball joint linkages are engineered with hardened surfaces to significantly reduce wear in high-frequency applications. The 440C ball is hardened to HRC 58 and ground to a precise spherical radius for consistent, predictable friction characteristics across the service life of the joint.

Fast Sampling for OEM Integration

Profab Machine works closely with brands to create linkage systems that integrate directly into their equipment. Whether it’s a CAD file, material conversion, or specific tolerance requirement, we quickly provide samples and expert feedback to accelerate your product development.

XRF Grade Verification + Material Certs

All 316L and 17-4PH material lots are verified by XRF spectrometry before production begins. Molybdenum content in 316L is confirmed at 2.0–3.0%. Material test certificates to EN 10204 3.1 are available for offshore and classification society projects.

The More You Order, the More You Save

We are the original manufacturer — eliminate all unnecessary middlemen. Profab provides tiered pricing at 100, 500, and 1,000+ quantities with every quote. Flexible terms for long-term OEM partnerships.

Technical Reference

Thread Sizes & Dimensions

Thread (mm)	Stud Thread (mm)	Thread (inch)	Stud Thread (inch)
M5x0.8	M5x0.8	10-32-2B	10-32-2A
M6*1.0	M6*1.0	1/4-28-2B	1/4-28-2A
M8*1.25	M8*1.25	5/16-24-2B	5/16-24-2A
M10*1.5	M10*1.5	3/8-24-2B	3/8-24-2A
M12*1.75	M12*1.75	7/16-20-2B	7/16-20-2A
M14*1.5	14*1.5	1/2-20-2B	1/2-20-2A
M14*2.0	M14*2.0	5/8-18-2B	5/8-18-2A
M16*1.75	M16*1.75	Custom	Custom
Custom	Custom

FAQ

Common Questions

Not seeing your question? Email us at [email protected] and we typically reply same day.

How do your ball joints perform in extreme temperatures and environments?

Built with 304/316 stainless steel and optional high‑temp seals, our ball joints operate from –40 °C to +200 °C. They’re corrosion‑resistant against salt spray, chemicals, and moisture—ideal for marine, off‑road, and industrial settings.

What factors do you consider when selecting stainless steel ball joints?

When selecting ball joints, you should consider the following factors: load carrying capacity, permissible swing angle, sealing and dustproof performance, whether or not lubrication is required, working temperature and corrosive environment, and installation method.

How To Lubricate Ball Joints?

Clean the Zerk Fitting

Use a rag to wipe all dirt, crusty grease, and road grime off the Zerk fitting.

Attach the Grease Gun

Push the grease gun coupler onto the Zerk fitting. You should feel it “snap” or lock into place. If it feels loose, the grease might squirt out the sides instead of going inside.