Buttweld Cap
What is a Buttweld Cap?
A Buttweld Cap is a pipe fitting used to seal the end of a pipe or pressure vessel. It is welded to the pipe end to stop the flow of fluid or gas, acting as a permanent barrier. These caps are commonly used for pipe termination, test heads, pressure holding, or future expansion.
Buttweld caps are essential in oil & gas, petrochemical, food processing, marine, and structural piping systems, ensuring protection from contaminants, corrosion, and mechanical damage.
Key Features
- Securely Seals Pipe Ends – Provides tight closure for pipeline termination.
- Seamless & Welded Options – Designed for high-pressure applications.
- Wide Wall Compatibility – Fits SCH 10 to XXS pipe thicknesses.
- Reduces Stress & Corrosion – Enhances durability at pipe ends.
- Standards Certified – Manufactured per ASME, MSS, DIN, and EN norms.
Types of Buttweld Caps
- Hemispherical Pipe Cap
- Elliptical End Cap
- Flat End Cap (custom on request)
Specifications
Mechanical Properties
Chemical Composition
Equivalent Grades
Weight Chart
Specifications
| Parameter | Details |
|---|---|
| Sizes | ½” to 48″ (DN15 – DN1200) |
| Wall Thickness | SCH 10 to SCH XXS |
| Material Options | CS, SS 304/316, Duplex, Alloy Steel |
| Standards | ASME B16.9, MSS-SP-43, DIN 2617 |
| Manufacturing | Seamless / Welded, Hot Formed |
| Property | Typical Value |
|---|---|
| Tensile Strength | 485 – 750 MPa |
| Yield Strength | 205 – 450 MPa |
| Elongation | ≥ 20% |
| Hardness | 120 – 250 HB |
| Temperature Range | -46°C to +650°C |
| Element | Composition (%) |
|---|---|
| Carbon (C) | 0.08 – 0.35 |
| Manganese (Mn) | 0.60 – 1.65 |
| Silicon (Si) | 0.15 – 0.80 |
| Chromium (Cr) | 16.0 – 20.0 |
| Nickel (Ni) | 8.0 – 14.0 |
| Molybdenum (Mo) | 2.0 – 3.0 |
| Phosphorus (P) | ≤ 0.035 |
| Sulfur (S) | ≤ 0.040 |
| Iron (Fe) | Balance |
| Standard | Equivalent Grades |
|---|---|
| ASTM | A234 WPB (CS), A403 WP304/316 (SS) |
| ASME | B16.9 |
| MSS-SP | SP-43 |
| DIN | 2617 |
| EN | EN 10253 |
| Cap Type | Size (inches) | Weight per 100 pcs (kg) |
|---|---|---|
| Pipe Cap | 2″ | 110 |
| Pipe Cap | 4″ | 180 |
| Pipe Cap | 6″ | 250 |
Applications of Buttweld Caps
Construction &
Infrastructure
Automotive & Heavy
Equipment
Manufacturing &
Fabrication
Medical & Laboratory
Equipment
Electrical &
Electronics Assembly
Oil, Gas & Petrochemical
Installations
Do you have questions?
What is the purpose of a buttweld cap in a pipeline?
It permanently seals the end of a pipe, preventing leakage or environmental exposure.
Are pipe caps removable?
No, they are welded and permanent. For removable ends, threaded caps or flanged blanks are used.
Can caps be used for hydro testing?
Yes, pipe caps are ideal for pressure testing and closure during commissioning.
Are custom shapes or bevels available?
Yes. We supply custom beveled or flat caps as per client drawings.
