Ring Type Pipe Joint, also known as clamp type flexible pipe joint,
is a specialized piping system joint designed to connect pipes while allowing flexibility to absorb
thermal expansion, contraction, and misalignment due to foundation settlement or vibration. These flexible
pipe joints are engineered for high-pressure applications in industries such as petrochemical, power
generation, water treatment, and municipal infrastructure, conforming to standards like GB/T 19682 and international
equivalents. Featuring a clamping mechanism with rubber sealing rings, ring type pipe joint ensures
leak-free performance and corrosion resistance, making it ideal for boiler pipeline
protection in harsh environments.
The manufacturing process involves forging or casting the clamp body from carbon steel or stainless steel, paired
with high-elasticity rubber sealing rings (EPDM or NBR) and high-strength bolts for secure assembly. Ring
type pipe joint models like KRH and KRJ series are designed for pipe diameters from DN50 to DN2400,
with pressure ratings up to PN25 (2.5 MPa) and temperature ranges from -20°C to 80°C. The joint's flexible design
compensates for axial displacement up to 50mm, angular deviation up to 6°, and lateral offset up to 20mm, reducing
stress on pipelines. Surface treatments such as hot-dip galvanization or epoxy coating enhance corrosion
resistance, ensuring durability in corrosive media like seawater or acidic fluids.
Clamp pipe joint undergoes rigorous testing, including hydrostatic pressure, tensile strength, and
sealing integrity tests, to comply with GB/T 19682 and ISO standards. The rubber ring provides a watertight seal,
while the clamp's bolted design allows for easy installation and disassembly without special tools, making it
suitable for both buried and aboveground piping. In petrochemical plants, these joints handle thermal expansion in
long pipelines, preventing cracks or leaks, while in power plants, they absorb vibrations from pumps and valves. The
joint's comprehensive cost-performance ratio surpasses traditional flange connections, with lower installation time
and labor costs.
Compared to rigid joints like flanges or welded connections, thermal expansion joint types like
ring type pipe joint offer greater flexibility and ease of maintenance, reducing downtime during repairs. The KRH
series is ideal for high-pressure systems, while KRJ provides enhanced sealing for low-pressure applications. These
corrosion resistant joint solutions support various pipe materials, including ductile iron, steel,
and PVC, and can be customized for specific deflection angles or pressure classes. In municipal water systems, they
ensure reliable connections in underground pipelines, accommodating ground movement without failure.
Addressing challenges like pipeline stress, leaks, and corrosion in industrial systems, ring type pipe
joint delivers a flexible, durable solution for piping system joint needs. Its ability
to compensate for movement while maintaining pressure integrity makes it a preferred choice for engineers seeking
reliable boiler pipeline protection. Whether in petrochemical pipelines, power plant cooling
systems, or water supply networks, these joints ensure long-term performance, safety, and cost efficiency.
Technical Specifications of Pipe Expansion Joints (Nominal Pressure & Dimensional Details)
| Nominal Pressure (MPa) |
Nominal Diameter (DN Mm) |
Maximum Clearance At Pipe End (△ Mm) |
Maximum Angle (Θ°) |
Tube Deflection (F Mm/M) |
L₁ |
L |
D |
D₁ |
D₂ |
B |
B₁ |
Bolt |
| Diameter (D) |
Quantity |
| Mm |
Mm |
Pc. |
| 4 |
150 |
10 |
2.74 |
47 |
307 |
259 |
226 |
154 |
168 |
68 |
120-130 |
16 |
2 |
| 175 |
10 |
2.35 |
41 |
333 |
285 |
252 |
178 |
194 |
68 |
120-130 |
| 200 |
10 |
1.48 |
26 |
358 |
310 |
277 |
207 |
219 |
68 |
120-130 |
| 225 |
10 |
1.33 |
23 |
384 |
336 |
303 |
232 |
245 |
68 |
120-130 |
| 250 |
10 |
1.20 |
21 |
412 |
364 |
331 |
259 |
273 |
68 |
120-130 |
| 300 |
10 |
1.04 |
18 |
483 |
427 |
383 |
310 |
325 |
68 |
120-130 |
18 |
| 350 |
10 |
1.03 |
18 |
535 |
479 |
435 |
359 |
377 |
68 |
120-130 |
| 400 |
10 |
0.97 |
16 |
595 |
535 |
484 |
408 |
426 |
68 |
120-130 |
20 |
| 2.5 |
450 |
10 |
0.93 |
16 |
649 |
589 |
538 |
462 |
480 |
68 |
120-130 |
| 500 |
10 |
0.90 |
15 |
703 |
641 |
588 |
512 |
530 |
68 |
120-130 |
22 |
| 600 |
10 |
0.88 |
15 |
803 |
741 |
688 |
610 |
630 |
68 |
120-130 |
| 1.6 |
700 |
10 |
0.82 |
14 |
889 |
829 |
778 |
700 |
720 |
68 |
120-130 |
20 |
4 |
| 800 |
10 |
0.80 |
14 |
989 |
929 |
878 |
800 |
820 |
68 |
120-130 |
| 900 |
10 |
0.73 |
12 |
1093 |
1031 |
978 |
900 |
920 |
68 |
120-130 |
22 |
| 1000 |
10 |
0.70 |
12 |
1193 |
1131 |
1078 |
1000 |
1020 |
68 |
120-130 |
- The theoretical mass includes the mass of clamps, terminations, sealing rubber rings, bolts and nuts.
- The clamp with nominal diameter of 150 - 700 is composed of two lobes, and the clamp with nominal diameter greater than 700 is composed of four lobes.
- Special requirements can be designed and manufactured separately.
