Torispherical Head

Torispherical head is a type of vessel head consisting of a dish with a toroidal section (spherical cap centered on the vessel) joined to a cylindrical section.

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Torispherical head (or flanged and dished head), These heads have a dish with a fixed radius (r1), the size of which depends on the type of torispherical head. The transition between the cylinder and the dish is called the knuckle. The knuckle has a toroidal shape.

These heads have a dish with a fixed radius, the size of which depends on the type of torispherical head. The transition between the cylinder and the dish is called the knuckle. The knuckle has a toroidal shape.

Vessel dished ends are mostly used in storage or pressure vessels in industry. These ends, which in upright vessels are the bottom and the top, use less space than a hemisphere (which is the ideal form for pressure containments) while requiring only a slightly thicker wall.

Torispherical head for boiler according DIN28011

Material

• Carbon steel tank ends/caps, flat dished head: SA516 GR60N,GR70N
• Stainless steel ellipsoidal dished end, elliptical tank head: SA240 304, 316
• Titanium alloy pressure vessel ends: SB256 GR1, GR2, GR5

Usage of Torispherical head

Torispherical head are commonly used in the design and construction of tanks and pressure vessels that operate under high pressure conditions. They are typically used at the end of cylindrical vessels where the transition is made from the cylindrical part to the end closure.

Some common applications of elliptical heads include:

• Pressure vessels: Torispherical head are frequently used as end closures for pressure vessels such as boilers, reactors, and distillation columns. These vessels are used in industries such as oil and gas, chemical processing, and power generation.
• Tanks: Torispherical head can be used in the construction of storage tanks for liquids or gases such as water, fuel, and natural gas. They provide a smooth transition between the tank body and the tank head.
• Heat exchangers: Torispherical head can also be used in the construction of heat exchangers such as shell-and-tube heat exchangers, which are used in a wide range of industries including food processing, pharmaceuticals, and HVAC.

Torispherical head are widely used in various industries where pressure vessels, tanks, or heat exchangers are required to operate at high pressures and temperatures. The specific application, size, material, and thickness of an elliptical head depend on the requirements and design standards of the project.

Torispherical head Dimensional Characteristics:

Compared with elliptical head, due to its easier manufacturing processes, the torispherical head is often used in addition to the pressure is larger diameter pressure vessel.

With the same same design conditions with the same design pressure, design temperature and material, your calculated wall thickness under internal pressure will be approximately half of the shell thickness.

For example, if you have calculated your shell thickness under internal pressure and obtained 12 mm, your hemispherical head thickness also will be approximately 6 mm.

The inside depth of your Torispherical head will be one-half of head inside diameter (h = D/2).

Dimensional Inspection of Pressure Torispherical head

You need to make a dimensional inspection on the pressure Torispherical head for any effort for the fit-up process. The dimensional inspection is done on the knuckle radius, crown radius, skirt length, depth and thickness.

We are manufacturer of End caps 48inch api 5l x46 carbon steel din28011 and supply high quality End caps 48inch api 5l x46 carbon steel din28011 in both large and small quantities worldwide and offer you the best prices in the market.

Pipeline steel plate API 5L PSL1 X46 and Pipeline steel coil API 5L PSL1 X46 are mainly used in making steel pipes for pipeline which transporting oil and gas.

Technical Requirements & Additional Services:

• Drop weight test (DWTT)
• Low temperature impacting test
• Ultrasonic test under EN 10160,ASTM A435,A577,A578
• Issued Orginal Mill test certificate under EN 10204 FORMAT 3.1/3.2
• Shot blasting and Painting,Cutting and welding as per end user’s demands

What are the differences Between Elliptical Head and Torispherical Heads?

Elliptical heads and torispherical heads are two types of products, so there is no doubt that they are different in terms of shape and design. In addition, there are also many differences in the machining process, and it is obvious that torispherical heads are much easier to machine. The ellipsoidal head is deformed under pressure, which means that it tends to produce opposite radial displacement in the joint. The torispherical head, on the other hand, is formed by the stamping process, which is basically not difficult.

The bending radius of ellipsoidal head is continuous and no stress is generated, so it can be used in higher pressure vessels; while the joint of disc-shaped head is discontinuous and stress exists, so this type of head is chosen for low pressure vessels. But as far as stress is concerned it is better to have ellipsoidal heads, but the metal consumption of torispherical heads will be lower.

1. When the pipeline reaches the head and is not ready to be extended now, the head is welded to the pipe and used as an end.
2. Used on pressure vessels with a head on the top and bottom and a straight pipe section in the middle, used as a storage tank for pressure vessels.

The ellipsoidal head with the ratio of the long axis to the short axis of the rotating ellipsoidal sphere bus is 2.0, which is usually called standard ellipsoidal head. The mechanical properties of ellipsoidal heads are second only to those of hemispherical heads but better than those of disc-shaped heads. As the depth of ellipsoidal head is between that of hemispherical head and disc-shaped head, the requirements for stamping equipment and moulds as well as the manufacturing difficulty are also between them, i.e., it is easier than hemispherical head and more difficult than disc-shaped head. In recent years, the adoption of spinning manufacturing process has brought convenience to the manufacture of large diameter ellipsoidal heads. Elliptical heads are widely used for medium and low pressure vessels due to their better overall performance.

The elliptical head is a very well stressed head as better technology has been adopted in recent years and it is easier to manufacture larger elliptical heads. As a result, its overall performance is very good and it is suitable for low and medium pressure vessels. It is easier to use and better made.

What is the difference between ellipsoidal head and Torispherical head?

1. Different shapes.

Elliptical head, also called oval head, consists of half ellipsoidal sphere and cylindrical straight side part. It has the advantages of good force on the head of hemispherical head and shallow depth on the head of disc-shaped head. As the curvature of the elliptical bend is smooth and continuous, the stresses in the head are distributed relatively evenly.

The disc-shaped head, also known as a spherical head with sides. It consists of a spherical surface, a cylindrical straight edge of a certain height and a transition part which connects the above two parts and whose radius of curvature is smaller than the radius of the spherical surface.

2. Different forces.

An elliptical head is stronger than a dished head, but an elliptical head of the same diameter is somewhat deeper than a dished one and is slightly more difficult to manufacture than a dished head. It consumes more materials and costs a bit more, and the difference in volume remains small.

3. If you choose ellipsoidal head and disc-shaped head which conform to JB4746 "Head for Steel Pressure Vessel" standard, it is relatively better to use ellipsoidal head because the wall thickness calculated by ellipsoidal head for the same pressure, temperature and diameter according to GB150 is smaller than that elected with non-standard ellipsoidal head.

Features

Pipe caps fit over or are welded onto the end of a pipe, providing a liquid or gas tight seal.

End Caps are used for connecting pipes of different diameters and find wide applications in various chemicals, construction industries, paper, cement & ship builders.

Pipe caps are widely well-known for the utmost output and outstanding results that it gives.

It is commonly made from the one steel plate, so it should be seamless. The pipe end caps are available in various shapes, like the hemispherical, oval, round etc.

Size

End cap is commonly made from the one steel plate, so it should be seamless. The pipe end caps are available in various shapes, like the hemispherical, oval, round etc.

Size range: 1/2 to 56 inches (DN15 to DN1400)

Pressure: SCH5 to SCH160v

Wall Thickness:sch10, sch20, sch30, std, sch40, sch60, xs, sch80, sch100, sch120, sch140, sch160, xxs, sch5s, sch20s, sch40s, sch80s

Max. wall thickness: 200mm

Size range of A234 WPB large diameter eipe cap

Based on different materials, pipe caps include carbon steel cap, stainless steel cap, and alloy steel cap etc.

Depending on their construction, pipe caps contain threaded cap, tapered cap and anti-roll cap etc.

End Caps DIN 2617 dimensions standard

DIN 28011 pipe end cap dimensions

ISO - dimensions

Metric dimensions

Cap geometry

Theoretical weight of cap fittings

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Standard

Pipe fitting dimensions are in either metric or Standard English.

Because pipe fitting covers Pipe Fitting Dimensions several aspects, only the most common pipe fitting sizes can be given here. The most applied version is the 90° long radius and the 45° elbow, while the 90° short radius elbow is applied if there is too little space. The function of a 180° elbow is to change direction of flow through 180°. Both, the LR and the SR types have a center to center dimension double the matching 90° elbows. These fittings will generally be used in furnesses or other heating or cooling units.

Some of the standards that apply to buttwelded fittings are listed below. Many organizations such as ASME, ASTM, ISO, MSS, etc. have very well developed standards and specifications for buttwelded fittings. It is always up to the designer to ensure that they are following the applicable standard and company specification, if available, during the design process.

Some widely used pipe fitting standards are as follows:

ASME: American Society for Mechanical Engineers
This is one of the reputed organizations in the world developing codes and standards.
The schedule number for pipe fitting starts from ASME/ANSI B16. The various classifications of ASME/ANSI B16 standards for different pipe fittings are as follows:

• ASME/ANSI B16.1 – 1998 – Cast Iron Pipe Flanges and Flanged Fittings
• ASME/ANSI B16.3 – 1998 – Malleable Iron Threaded Fittings
• ASME/ANSI B16.4 – 1998 – Cast Iron Threaded Fittings
• ASME/ANSI B16.5 – 1996 – Pipe Flanges and Flanged Fittings
• ASME/ANSI B16.11 – 2001 – Forged Steel Fittings, Socket-Welding and Threaded
• ASME/ANSI B16.14 – 1991 – Ferrous Pipe Plugs, Bushings and Locknuts with Pipe Threads
• ASME/ANSI B16.15 – 1985 (R1994) – Cast Bronze Threaded Fittings
• ASME/ANSI B16.25 – 1997 – Buttwelding Ends
• ASME/ANSI B16.36 – 1996 – Orifice Flanges etc.

ASTM International: American Society for Testing and Materials
This is one of the largest voluntary standards development organizations in the world. It was originally known as the American Society for Testing and Materials (ASTM).

• ASTM A105/A105M – Specification for Carbon Steel Forgings for Piping Applications
• ASTM A234/A234M – Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service
• ASTM A403/A403M – Specification for Wrought Austenitic Stainless Steel Piping Fittings
• ASTM A420/A420M – Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Low-Temperature Service

AWWA: American Water Works Association

AWWA About – Established in 1881, the American Water Works Association is the largest nonprofit, scientific and educational association dedicated to managing and treating water, the world’s most important resource.

• AWWA C110 – Ductile-Iron and Gray-Iron Fittings, 3 Inch Through 48 Inch (75 mm Through 1200 mm), for Water and Other Liquids
• AWWA C208 – Dimensions for Fabricated Steel Water Pipe Fittings

ANSI: The American National Standards Institute

ANSI is a private, non-profit organization. Its main function is to administer and coordinate the U.S. voluntary standardization and conformity assessment system. It provides a forum for development of American national standards. ANSI assigns “schedule numbers”. These numbers classify wall thicknesses for different pressure uses.

MSS STANDARDS: Manufacturers Standardization Society
The Manufacturers Standardization Society (MSS) of the Valve and Fittings Industry is a non-profit technical association organized for development and improvement of industry, national and international codes and standards for: Valves, Valve Actuators, Valve Modification, Pipe Fittings, Pipe Hangers, Pipe Supports, Flanges and Associated Seals

• MSS SP-43 – Wrought Stainless Steel Butt-Welding Fittings Including Reference to Other Corrosion Resistant Materials
• MSS SP-75 – Specifications for High Test Wrought Buttwelding Fittings
• MSS SP-73 – Brazing Joints for Copper and Copper Alloy Pressure Fittings
• MSS SP-83 – Class 3000 Steel Pipe Unions, Socket-Welding and Threaded
• MSS SP-97 – Integrally Reinforced Forged Branch Outlet Fittings — Socket Welding, Threaded, and Buttwelding Ends
• MSS SP-106 – Cast Copper Alloy Flanges and Flanged Fittings Class 125,150, and 300
• MSS SP-119 – Factory-Made Wrought Belled End Socket Welding Fittings

Difference between “Standard” and “Codes”:

Piping codes imply the requirements of design, fabrication, use of materials, tests and inspection of various pipe and piping system. It has a limited jurisdiction defined by the code. On the other hand, piping standards imply application design and construction rules and requirements for pipe fittings like adapters, flanges, sleeves, elbows, union, tees, valves etc. Like a code, it also has a limited scope defined by the standard.

Factors affecting standards: “Standards” on pipe fittings are based on certain factors like as follows:

• Pressure-temperature ratings
• Size
• Design
• Coatings
• Materials
• Marking
• End connections
• Dimensions and tolerances
• Threading
• Pattern taper etc.

BSP: British Standard Pipe

BSP is the U.K. standard for pipe fittings. This refers to a family of standard screw thread types for interconnecting and sealing pipe ends by mating an external (male) with an internal (female) thread. This has been adopted internationally. It is also known as British Standard Pipe Taper threads (BSPT )or British Standard Pipe Parallel (Straight) threads (BSPP ). While the BSPT achieves pressure tight joints by the threads alone, the BSPP requires a sealing ring.

JIS: Japanese Industrial Standards

This is the Japanese industrial standards or the standards used for industrial activities in Japan for pipe, tube and fittings and published through Japanese Standards Associations.

NPT: National Pipe Thread

National Pipe Thread is a U.S. standard straight (NPS) threads or for tapered (NPT) threads. This is the most popular US standard for pipe fittings. NPT fittings are based on the internal diameter (ID) of the pipe fitting.

BOLTS & NUTS

We are manufacturer of Flange bolts & Nuts and supply high quality

• A193 = This specification covers alloy and stainless steel bolting material for pressure vessels, Valves, flanges, and fittings for high temperature or high pressure service, or other special purpose applications.
• A320 = Standard Specification for Alloy-Steel and Stainless Steel Bolting Materials for Low-Temperature Service.
• A194 = Standard specification for nuts in many different material types.

AN: Here, “A” stands for Army and “N” stands for Navy

The AN standard was originally designed for the U.S. Military. Whenever, a pipe fitting is AN fittings, it means that the fittings are measured on the outside diameter of the fittings, that is, in 1/16 inch increments.

For example, an AN 4 fitting means a fitting with an external diameter of approximately 4/16″ or ¼”. It is to be noted that approximation is important because AN external diameter is not a direct fit with an equivalent NPT thread.

Dash (-) size

Dash size is the standard used to refer to the inside diameter of a hose. This indicates the size by a two digit number which represents the relative ID in sixteenths of an inch. This is also used interchangeably with AN fittings. For example, a Dash “8” fitting means an AN 8 fitting.

ISO: International Organization for Standardization

ISO is the industrial pipe, tube and fittings standards and specifications from the International Organization for Standardization. ISO standards are numbered. They have format as follows:

“ISO[/IEC] [IS] nnnnn[:yyyy] Title” where

• nnnnn: standard number
• yyyy: year published, and
• Title: describes the subject

General standard

Wide variety for all areas of application

Delivery

Inspection

Visual Inspection is conducted on fittings to check any surface imperfections. Both fittings body and weld are checked for any visible surface imperfections such as dents, die marks, porosity, undercuts, etc. Acceptance as per applicable standard.

Packing

For packing of carbon steel flanges with painting,we would use the bubble wrap to protect the painting.For flanges without painting or oiled with long-term shipment,we would suggest client to use the anti-tarnish paper and plastic bag to prevent the rust.