Industrial Casters. Engineered for Spec.
Stem casters are caster assemblies that mount via a vertical stem inserted into a tubular receiver — the standard mount for office chairs, medical carts, institutional furniture, and OEM equipment with factory-drilled receivers. CasterHQ stocks 560 stem caster configurations with threaded, grip-ring, expanding-adapter, and round-stem options rated 40 lb to 1,400 lb per caster.
Six standard stem types cover 95% of applications. Threaded stem (7/16"-14, 1/2"-13, 5/8"-11 most common) — screws into a tapped hole or weld nut. Grip-ring stem (7/16" × 1-3/8", 1/2" × 1-1/2") — friction-held in a drilled bore with a steel ring. Expanding adapter stem — fits inside a tubular leg and expands to grip. Round stem — smooth shaft for legacy or custom OEM receivers. Measure existing stem diameter + length + thread pitch before ordering.
Measure three things: (1) Stem diameter (e.g., 7/16" or 1/2"), (2) Thread pitch (threads per inch — 7/16"-14 means 14 TPI), (3) Stem length from under the caster to the tip. Most modern office and institutional receivers use 7/16"-14 UNC thread, 1" length. Heavier casters use 1/2"-13 UNC. Wrong thread pitch strips the receiver on the first install — always verify before ordering.
Yes, with an adapter plate or by welding a plate onto the existing frame. Conversion is common on institutional furniture being upgraded for heavier loads. Our engineers supply adapter plates sized to match the equipment frame and preserve OAH. Call 844-439-4335 for custom conversion fittings.
What's the most common stem size for office chairs? 7/16″ × 7/8″ grip-ring stem. It's the global industry standard since 1985 across virtually all commercial office seating.
Do you make custom stem sizes? Yes, on minimums of 100+ units with 3-4 week lead time. Metric threading (M10, M12) also available. Call 844-439-4335.
Can I put a stem caster on a plate receiver? Only with an adapter. Don't weld or cross-thread — use a proper stem-to-plate adapter to preserve load rating.
What stem caster has the highest load rating? 1-1/4″ × 1-1/2″ threaded stem with 6″ polyurethane wheel rated 1,400 lb per caster. Used in heavy institutional and OEM equipment.
Are your stem casters stainless? Available in full 304 stainless across threaded, grip-ring, and round stems for clean room, food service, medical, and marine applications.
Stem casters have a reduced load capacity vs equivalent plate casters because the stem transfers load through a single axial shaft rather than a 4-bolt plate. Apply the N-1 method (divide by 3, multiply by 1.25), then apply stem safety: threaded stem = 1.00 baseline, grip-ring = 0.90, expanding adapter = 0.85. Example: a 900 lb cart with grip-ring stems needs casters rated ≥ 417 lb each (900 ÷ 3 × 1.25 ÷ 0.90).
| Stem Type | Load Range | Mount | Installation | Best Use |
|---|---|---|---|---|
| Threaded Stem Most Common | 75–1,400 lb | Tapped hole / weld nut | Screw in, Loctite blue | Industrial, institutional, OEM |
| Grip-Ring Stem | 40–250 lb | Drilled bore | Push-in friction | Office chairs, retail fixtures |
| Expanding Adapter | 75–500 lb | Tubular leg | Insert, tighten expander | Institutional furniture |
| Round Stem | 75–600 lb | Smooth bore + set screw | Insert + locking | Legacy or custom OEM |
Needed 3,200 replacement office chair casters across 18 locations after a warranty recall. CasterHQ shipped the exact 7/16-inch grip-ring match in 48 hours, standardized our entire office furniture maintenance line on one SKU. Zero failures 14 months in.
Application engineers on staff · ISO-certified facility · 50,000+ businesses served · 100+ combined years in caster design
These calculators apply to any caster application—even if you’re browsing a different category. Use them to estimate load rating per caster, select wheel material, and estimate push/pull force. Expand any tool for full analysis + a share-ready spec line.
Engineering Tools Hub
All tools + dedicated pages (best for sharing and EEAT). Open hub
Load Calculator (dedicated)
Share this page when discussing load rating per caster. Open load tool
Wheel Diameter Calculator
Publish the dedicated page, then replace this link. Find in hub
Failure Diagnosis Tool
Publish the dedicated page, then replace this link. Find in hub
Trusted by 100,000+ Industrial and Commercial Buyers | 98.7% on-time shipment rate
Designed for engineers, manufacturers, and material handling professionals
