Specifications

Dimensions below are the standard production range for rings and boss heads. Sizes are given as a selection hint only; please check the actual product.

Request custom specs

Iron ring sizes

Inner dia. (mm)	Outer dia. (mm)	Stem (mm)	Wire (mm)	Suitable for
40	50	90	4	Small funnels, crucibles
60	72	100	4	Funnels, evaporating dishes
80	93	110	5	Flasks, standard funnels
100	114	120	5	Large flasks, dishes
120	135	130	6	Large flasks, large funnels
150	167	140	6	Large vessels, batch support

Boss head sizes

Model	Rod bore (mm)	Aux. bore (mm)	Length (mm)	Material
Small	10	8	70	Galvanised steel
Medium	12	10	85	Galvanised steel
Large	14	12	100	Galvanised steel

Values are typical; reasonable tolerances apply between production batches. Please rely on actual measurement.

📌 Customization:
• Wire gauze or ceramic fibre mesh can be supplied with the ring
• Rings and boss heads also available separately
• Complete sets with retort stands and clamps available

Product Description

1. Overview

An iron ring is a circular support with a stem. The stem is held in a boss head on the rod, and the ring carries a funnel, flask, evaporating dish or wire gauze. For heating, wire gauze is placed on the ring so the flame or heat source spreads evenly under the glassware.

The boss head is the connecting piece: one bore fits over the rod and the other takes the stem of a ring, clamp or thermometer holder. Two screws lock independently, so height and direction can be set freely, making it the universal hub of a retort stand.

Ring inner diameters commonly run from 40mm to 150mm. Small rings suit small funnels and crucibles, large rings take flasks, dishes and large funnels. Check that the ring inner diameter suits the vessel base and that the boss head bore suits the rod.

🔬 Types & Features:
Ring support — a level base for funnels, flasks and wire gauze.
Boss head hub — one fitting sets both height and direction.
Galvanised — resists rust in humid air and reagent vapour.
Full range — inner diameters from 40 to 150mm.

2. Key Parameters

Ring inner dia.: 40 / 60 / 80 / 100 / 120 / 150 mm
Boss head bore: suits rods of about 10 to 12 mm
Material: galvanised steel with anti-rust finish
Locking: screw and grub screw clamping
Fitting: retort stands, universal clamps, flask clamps, gauze
Applications: heating support, filtration support, fitting joints

3. Material & Workmanship

Rings and boss heads are machined from steel and galvanised, giving an even, dense coating that resists rust and seizing during long exposure to humid air and reagent vapour. Screw tips are finished so they do not damage the rod surface.

Handling tip: fit the boss head to the rod first, then insert the ring stem and tighten both screws. When heating, always place wire gauze on the ring so glassware never meets an open flame.

Applications

Typical Uses

Heating support

ring and gauze under a heated flask

Filtration support

holding a funnel and filter paper

Evaporation

carrying an evaporating dish for concentration

Fitting joints

mounting clamps at any height on the rod

Industries

Chemical synthesis assembling heating and filtration set-ups
Analytical testing supporting sample preparation apparatus
Teaching laboratories demonstrating basic apparatus
Pharmaceutical R&D carrying and fixing pilot set-ups
Materials research supporting and adjusting high-temperature rigs

Selection Guide

Select by what is supported

Supported item	Suggested inner dia.	Notes
Small funnels, crucibles	40 ~ 60mm	A small ring supports more steadily
Evaporating dishes, standard funnels	60 ~ 80mm	Balance of stability and access
Flasks (250 to 500 mL)	80 ~ 100mm	Ring must overlap the flask base
Large vessels	120 ~ 150mm	Use with a large-base stand

💡 Tips: Match the diameter — the ring must be smaller than the vessel to hold it.
Gauze is essential — never let glass meet an open flame.
Both screws — tighten both boss head screws to stop slipping.
Check the bore — confirm the boss head suits the rod diameter.

Operation & Maintenance

Operation Guide

Fitting a ring and boss head looks simple, but locking and diameter matching decide how safe the set-up is. The steps below cover routine use.

Before Use

Check the ring for distortion and the galvanising for damage
Check the boss head screws for smooth travel and stripped threads
Confirm the ring inner diameter suits the vessel
Confirm the boss head bore suits the rod diameter
Have wire gauze ready for any heating task

Procedure

Slide the boss head onto the rod and tighten the rod-side screw to position it
Insert the ring stem into the other bore and tighten the accessory screw
Adjust the ring height and orientation until it is level and firm
Place wire gauze on the ring when heating
Set the flask or funnel in the centre of the ring so it cannot tip
Push the assembly gently to confirm neither ring nor boss head moves
To dismantle, remove the vessel first, then release the screws and lift the ring off

Cleaning & Care

Wipe reagent residues off the ring and boss head after use
Dry off water promptly so the galvanising is not wet for long periods
Add a little lubricant to the screws to keep them free
Remove light rust with fine abrasive paper and apply a thin anti-rust film
Store dry and avoid load that could distort the ring

💡 Lab veteran tips: Ring smaller than the vessel — a ring larger than the vessel lets it fall straight through.
Never skip the gauze — direct flaming of glass causes rapid failure.
Tighten both screws — locking only one is the most common cause of a slip.
Moderate height — a very high ring raises the centre of gravity and reduces stability.

Care & Notes

Show care & notes

⚠️ Safety Notes

Gauze required

always use wire gauze over an open flame

Diameter check

the ring must be smaller than the vessel

Screw locking

tighten both boss head screws

Load limit

large vessels need a large ring and a stable stand

Heat protection

let the ring and vessel cool before removal

Iron Ring & Boss Head

Specifications

Iron ring sizes

Boss head sizes

Product Description

1. Overview

2. Key Parameters

3. Material & Workmanship

Applications

Heating support

Filtration support

Evaporation

Fitting joints

Selection Guide

Select by what is supported

Operation Guide

Before Use

Procedure

Cleaning & Care

Care & Notes

Gauze required

Diameter check

Screw locking

Load limit

Heat protection

Need Iron Ring & Boss Head?

Iron Ring & Boss Head

Specifications

Iron ring sizes

Boss head sizes

Product Description

1. Overview

2. Key Parameters

3. Material & Workmanship

Applications

Heating support

Filtration support

Evaporation

Fitting joints

Selection Guide

Select by what is supported

Operation Guide

Before Use

Procedure

Cleaning & Care

Care & Notes

Gauze required

Diameter check

Screw locking

Load limit

Heat protection

Related Products

Retort Stand

Lab Jack

Universal Clamp & Flask Clamp

Burette Clamp

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