Single Sphere Rubber Expansion Joint

One rubber arch between two flanges. Absorbs pump vibration, pipe movement and small misalignment. Standard sizes DN32–DN1000, larger up to DN3200.

Size Range: DN32–DN3200 (1¼"–128")
Pressure: PN10 / PN16 / PN25
Rubber: EPDM / NBR / NR / CR / IIR
Flange: Carbon steel, SS304, SS316L
Drilling: EN 1092-1, ASME B16.5, JIS, GB
Options: Control rods, vacuum ring, PTFE lining

Single Sphere Rubber Expansion Joint Dimensions

Standard sizes DN32 to DN1000. All dimensions in mm. Bolt data shown to GB/T 9115; EN, ASME and JIS drilling on request.

DN	Inch	Length L	Bolts	Bolt hole Ø	Bolt circle	Axial movement		Lateral	Angular
DN	Inch	Length L	Bolts	Bolt hole Ø	Bolt circle	Extension	Compression	Lateral	Angular
32	1¼"	95	4	18	100	6	9	9	15°
40	1½"	95	4	18	110	6	10	9	15°
50	2"	105	4	18	125	7	10	10	15°
65	2½"	115	4	18	145	7	13	11	15°
80	3"	135	4	18	160	8	15	12	15°
100	4"	150	8	18	180	10	19	13	15°
125	5"	165	8	18	210	12	19	13	15°
150	6"	180–200	8	23	240	12	20	14	15°
175	7"	200	8	23	240	12	20	14	15°
200	8"	210–250	8	23	295	12	25	22	15°
225	9"	200	8	23	295	16	25	22	15°
250	10"	230	12	23	350	16	25	22	15°
300	12"	245	12	23	400	16	25	22	15°
350	14"	255	16	23	460	16	25	22	15°
400	16"	255	16	25	515	16	25	22	15°
450	18"	255	20	25	565	16	25	22	15°
500	20"	255	20	25	620	16	25	22	15°
600	24"	260	20	30	725	16	25	22	15°
700	28"	260	24	30	840	16	25	22	15°
800	32"	260	24	34	950	16	25	22	15°
900	36"	260	28	34	1050	16	25	22	15°
1000	40"	260	28	34	1160	18	26	24	15°
DN1200 – DN3200 (48"–128") → Large Diameter Rubber Expansion Joint

Face-to-face length can be changed to fit an existing gap. Sizes outside this table are made to drawing.

How It’s Built

Five parts, each one you can specify.

1. Outer rubber — IIR, CR, EPDM, NR or NBR. Resists weather, ozone and wear.
2. Inner rubber — Same compound family, chosen for your medium.
3. Polyester cord fabric — Carries the pressure and holds the arch shape.
4. Flange — Q235 carbon steel, SS304 or SS316L. Rotates freely for easy bolt alignment
5. Steel wire ring — Locks the rubber bead into the flange so it cannot pull out.

Choose the Rubber by Medium and Temperature

The rubber decides what the joint can carry. Pick it by the hottest temperature in your line, then check the medium below.

Service temperature

Joint rating, continuous Compound limit, short periods only

NRNatural rubber

Joint rating, continuous: −30 to +70 °C . Compound limit, short periods only: −50 to +100 °C.

NBRNitrile

Joint rating, continuous: −20 to +80 °C . Compound limit, short periods only: −30 to +120 °C.

CRNeoprene

Joint rating, continuous: −20 to +100 °C . Compound limit, short periods only: −40 to +120 °C.

IIRButyl

Joint rating, continuous: −30 to +110 °C . Compound limit, short periods only: −40 to +140 °C.

EPDMEPDM

Joint rating, continuous: −30 to +120 °C . Compound limit, short periods only: −50 to +150 °C.

CSMHypalon®-type CSM

Joint rating, continuous: −20 to +110 °C . Compound limit, short periods only: −30 to +140 °C.

FKMViton®-type FKM

Joint rating, continuous: −15 to +150 °C . Compound limit, short periods only: −20 to +220 °C.

PTFEPTFE lined

Joint rating, continuous: −20 to +120 °C . Compound limit, short periods only: −40 to +200 °C.

Dark bars: continuous rating of the finished joint. Light bars: limit of the compound itself, short periods only.

How the compounds compare

Property	NR	NBR	CR	IIR	EPDM	CSM	FKM
Best for	Cold water, abrasive slurry	Oil, fuel, oily water	Seawater, outdoor lines	Acids, gas, vacuum	Water, hot water, outdoor	Oxidising chemicals, outdoor	Hot oil, solvents, strong acids
Mechanical
Tensile strength	Excellent	Good	Good	Fair	Good	Good	Good
Tear resistance	Excellent	Good	Good	Good	Fair	Good	Fair
Abrasion resistance	Excellent	Good	Good	Fair	Good	Good	Good
Flex life (movement)	Excellent	Good	Good	Good	Good	Good	Fair
Environment
Heat ageing	Fair	Good	Good	Excellent	Excellent	Excellent	Excellent
Ozone and sunlight	Poor	Poor	Good	Excellent	Excellent	Excellent	Excellent
Gas tightness / vacuum	Good	Good	Good	Excellent	Good	Good	Excellent
Water and hot water	Good	Good	Good	Excellent	Excellent	Good	Fair
Media
Mineral oil	Poor	Excellent	Good	Poor	Poor	Good	Excellent
Fuel, gasoline	Poor	Good	Fair	Poor	Poor	Fair	Excellent
Aromatics (benzene)	Poor	Poor	Poor	Poor	Poor	Fair	Excellent
Strong acids	Fair	Fair	Good	Good	Good	Good	Excellent
Weak acids	Good	Good	Excellent	Excellent	Excellent	Excellent	Excellent
Strong alkalis	Good	Good	Good	Excellent	Excellent	Excellent	Poor
Weak alkalis	Good	Good	Good	Excellent	Excellent	Excellent	Fair
Relative price	$	$$	$$	$$	$	$$$	$$$$

Can It Handle Your Media?

Pick your type of medium. Ratings are for room temperature — higher temperature or concentration lowers them. Send us the medium, concentration and temperature and we confirm the compound before production.

Search a medium

Medium	NR	NBR	CR	IIR	EPDM	CSM	FKM	PTFE lined	Usually built in
Fresh water, drinking water	A	A	A	A	A	A	A	A	EPDM
Hot water ≤ 100 °C	X	C	B	A	A	B	C	A	EPDM
Seawater, brine	A	A	A	A	A	A	A	A	CR or EPDM
Wastewater, sewage	B	A	A	A	A	A	A	A	EPDM or NBR
Oily water, bilge water	X	A	B	X	C	B	A	A	NBR
Mineral oil, hydraulic oil	X	A	B	X	X	B	A	A	NBR
Diesel, heating oil	X	A	C	X	X	C	A	A	NBR
Gasoline (petrol)	X	B	C	X	X	C	A	A	NBR or FKM
Hot oil above 80 °C	X	C	C	X	X	C	A	A	FKM
Vegetable oil, animal fat	C	A	B	B	C	B	A	A	NBR
Compressed air, oil-free	A	A	A	A	A	A	A	A	EPDM
Compressed air with oil mist	X	A	B	X	C	B	A	A	NBR
Natural gas, LPG	C	A	B	X	X	B	A	A	NBR
Flue gas (SO₂, moist)	C	C	B	A	A	A	A	A	EPDM or IIR
Sulphuric acid ≤ 50 %	B	C	B	A	A	A	A	A	EPDM
Sulphuric acid 50–96 %	X	X	X	C	C	B	A	A	PTFE lined or FKM
Hydrochloric acid ≤ 36 %	C	C	C	B	B	A	A	A	CSM or PTFE lined
Nitric acid ≤ 10 %	X	X	C	B	B	A	A	A	CSM or FKM
Phosphoric acid ≤ 85 %	B	B	B	A	A	A	A	A	EPDM
Acetic acid ≤ 10 %	B	B	B	A	A	B	B	A	EPDM
Caustic soda ≤ 50 %	A	B	A	A	A	A	B	A	EPDM
Ammonia solution	B	B	A	A	A	A	X	A	EPDM
Sodium hypochlorite ≤ 15 %	X	C	C	B	B	A	A	A	CSM or PTFE lined
Salt solutions	A	A	A	A	A	A	A	A	EPDM
Benzene, toluene, xylene	X	X	X	X	X	X	A	A	PTFE lined or FKM
Acetone, MEK	C	X	X	A	A	C	X	A	EPDM
Alcohols (ethanol, methanol)	A	B	A	A	A	A	C	A	EPDM
Ethylene glycol, antifreeze	A	A	A	A	A	A	A	A	EPDM
Abrasive slurry (sand, tailings)	A	B	B	C	B	B	C	C	NR
Lime and cement slurry	A	A	A	A	A	A	A	A	NR or EPDM
FGD slurry (gypsum, chlorides)	B	C	B	A	A	A	A	B	EPDM or IIR
No medium matches your search. Tell us the medium, concentration and temperature and we’ll check it for you.

ALittle or no effect BMinor effect, suitable CLimited — ask us first XNot suitable

Pressure, Temperature and Vacuum

Choose the class by working pressure. Vacuum is the most a joint of that class takes on a pump suction line.

Pressure classes

Class	Working pressure	Burst pressure	Vacuum
PN10	1.0 MPa	2.0 MPa	53.3 kPa (400 mmHg)
PN16	1.6 MPa	3.0 MPa	86.7 kPa (650 mmHg)
PN25	2.5 MPa	4.5 MPa	100 kPa (750 mmHg)

Temperature

−15 to +100 °C standard. −30 to +150 °C with a special compound.

Higher vacuum

Above the listed vacuum, order the joint with a vacuum support ring.

Rating by size

Size	Highest class
DN32 – DN300	PN25
DN350 – DN600	PN16
DN700 – DN1000	PN10

Larger bores carry a lower rating with the same rubber wall. Need more? We add plies and control rods — send your design pressure.

Flange Standards and Materials

Pick your pipe’s flange standard, class and size. If the numbers match your flange, our joint bolts straight on — no adapter, no re-drilling.

Check your flange

Standard Class Size

Flange OD — D

Bolt circle — K

Bolt holes — n × d

Bolt size

Flange thickness — t*

Standards we drill to

EN 1092-1

PN6 · PN10 · PN16 · PN25 · PN40 — same drilling as DIN, BS 4504, GB/T 9119
ASME B16.5 / B16.47

Class 150 · Class 300 · Series A 26"–60"; AWWA C207 Class D
JIS B2220

5K · 10K · 16K · 20K
AS 2129 / AS 4087

Table D · Table E · PN16
Your drawing

GOST, BS 10 or any special drilling; tapped holes on request

Flange drilling chart

EN · ASME · JIS · AS — OD, bolt circle, holes, thickness

Flange material and finish

Options

Add these when the job needs them — each one is priced separately.

Control rods

Stop over-extension under pressure thrust. Fit them at pump outlets or where the pipe is not anchored.

Vacuum support ring

A steel ring inside the arch keeps it from collapsing on suction lines.

PTFE lining

White PTFE liner for strong acids, solvents and food-grade media.

Tapped holes & custom drilling

Threaded bolt holes for wafer valves, or drilling to your drawing.

Why Buy From Our Factory

A rubber joint is a simple product. What decides whether it lasts is the right material for your working conditions — and then the price.

Working conditions confirmed first

Size, pressure, medium, temperature, length and flange drilling are checked against your data and sent back on a drawing before production starts.

Full material, nothing thinned

Flanges and unions to full thickness, cord plies matched to the pressure class, rubber compounded in-house for your medium.

Pressure tested before packing

Every joint is tested at 1.5 × working pressure and checked for leaks and bulging.

Factory price, quoted the same day

You buy from the production line, not through a trader. Send size, pressure and medium and get a price the same working day.

Where It’s Installed

Pump suction and discharge

Stops pump vibration and noise travelling down the line. Add a vacuum ring on the suction side.

HVAC chillers and cooling towers

Takes thermal movement and isolates vibration at chillers, cooling towers and AHUs.

Water treatment and pump stations

Compensates settlement and misalignment between pumps, valves and headers.

In Service

Rubber joints from our factory, photographed by customers on site.

Single Sphere Rubber Expansion Joint Price

What you pay depends on a few choices. Send them and we quote the same day.

What changes the price

Size : DN is the biggest factor
Rubber : EPDM and NR cost less than NBR, CR or PTFE lined
Pressure class : PN16 uses more plies than PN10
Flange : Galvanised carbon steel vs SS304 / SS316L
Options : Control rods, vacuum ring
Quantity : wholesale price is different with project price

Reference price

Size	Price per piece
DN50	Contact Us
DN100	Contact Us
DN150	Contact Us
DN200	Contact Us
DN300	Contact Us

EPDM, PN16, galvanised carbon steel flanges, EXW Gongyi / FOB Tianjin or Ningbo or Guangzhou. Prices change with steel and rubber costs.

Downloads

Datasheets, drawings and references for submittals.

Control rods

Single sphere datasheet

Dimensions DN32–DN1000, pressure classes, materials

2D drawing

2D drawing Half-section, opens in AutoCAD

For all our rubber joints

Flange drilling chart

EN, ASME, JIS, AS — holes, bolt circle, thickness

Rubber selection and chemical resistance chart

8 compounds, 40 media, temperature limits

Installation guide

Anchors, control rods, bolting sequence

EPDM body submittal

Water, hot water, outdoor lines

NBR body submittal

Oil, fuel and oily water

Frequently Asked Questions

What sizes do you make?

Standard sizes run from DN32 (1¼”) to DN1000 (40″). DN1200 to DN3200 are built on the same single-arch design — see our large diameter rubber expansion joints.

Which rubber should I choose for hot water?

EPDM. Standard EPDM handles hot water to about +100 °C; above that we use a heat-resistant EPDM compound. Tell us the maximum temperature.

Can I use it on a pump suction line?

Yes. Check the vacuum rating of the class you choose (53.3 kPa for PN10, 86.7 kPa for PN16). For more vacuum, order it with a vacuum support ring.

Do I need control rods?

Fit them when the pipe on either side is not anchored — usually at pump outlets and on high-pressure lines. They stop the joint over-extending under pressure thrust.

Can you drill the flanges to ANSI or JIS?

Yes. We drill to EN 1092-1, ASME B16.5 Class 150, JIS and GB, or to your drawing. Tapped bolt holes are available.

What is the MOQ and lead time?

MOQ 1 pcs. Common sizes in EPDM and NBR are usually in stock and ship in 3-7 days; other sizes take 10-20 days.

Send Your Size, Pressure and Medium

We reply with a drawing and a price within 24 hours on working days.

Send your size, pressure, medium, flange standard and quantity. This block follows the clean contact layout of your reference page.

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Single Sphere Rubber Expansion Joint

Single Sphere Rubber Expansion Joint Dimensions

How It’s Built