Vessel Dished Heads: Essential Components for Pressure Vessels

Vessel Dished Heads: Essential Components for Pressure Vessels

A vessel dished head, also known as an end cap, is a critical part of a pressure vessel, serving as an end closure. Its primary function is to seal the vessel, separating the internal contents from the external environment. In cylindrical vessels, the head typically takes the form of a curved, rotating shell.

These heads come in various shapes, broadly classified as convex, conical, flat, or combined. Convex heads are characterized by their outward-protruding surface, encompassing designs like hemispherical, ellipsoidal, dished (torispherical), and flanged spherical heads. Notably, some gas cylinders utilize combined-shape bottom heads with an inward-facing convex surface. This design optimizes strength while adhering to safety requirements.

Vessel dished heads are welded to the cylindrical body of the vessel. Based on their geometry, they are further categorized into spherical, ellipsoidal, torispherical (dished), spherical crown, conical, and flat types. Spherical, ellipsoidal, torispherical and spherical crown heads are collectively referred to as convex heads. Depending on the welding method, they can be classified as butt-welded or socket-welded heads. These components find widespread application in diverse vessels and equipment, including storage tanks, heat exchangers, towers, reactors, boilers, and separation units.

A wide range of materials are used in their construction. Common options include:

• Carbon Steel: (A3, 20#, Q235, Q345B, 16Mn, etc.)

• Stainless Steel: (304, 321, 304L, 316, 316L, etc.)

• Alloy Steel: (15Mo3, 15CrMoV, 35CrMoV, 45CrMo)

• Other Metals: Aluminum, Titanium, Copper, Nickel, and Nickel Alloys

Relevant Standards

The manufacturing and performance of vessel dished heads are governed by several industry standards, including:

• Pressure Vessel Head Standard: GB/T25198-2010

• Pipeline Standards: GB/T12459-2005, GB/T13401-2005

• Power Industry Standard: DL/T695-1999, D-GD87-0607

• Petrochemical Standards: SH3408-1996, SH3409-1996

Applications

Dished heads are commonly employed as ends (top and bottom in upright vessels) of storage tanks and pressure vessels. They offer a balance between space efficiency and structural integrity, requiring only slightly thicker walls compared to a hemispherical shape while providing good pressure containment.

Haipei Industry: Your Source for Vessel Dished Heads

Haipei Industry offers a comprehensive range of vessel dished heads and ends, including:

• Torispherical Heads

• Ellipsoidal Heads

• Hemispherical Heads

We provide various configurations tailored to your specific needs. For any inquiries or requirements, please contact us.