Ti Grade 5 Gr5 Grade 7 Gr7 Titanium Disc Titanium Hemispherical Head Dish Shaped

Product Specification

Ti Grade 5 Gr5 Grade 7 Gr7 Titanium Hemispherical Head Dish Shaped Titanium Equipment

The dish head (also known as a dish end, hemispherical head, or elliptical dish end) is a type of head used to close the end of cylindrical containers, ensuring the separation between the internal and external media. It serves as a structural component in various containers and equipment, such as storage tanks, heat exchangers, reactors, boilers, and separation equipment. These heads are critical for maintaining the integrity of the container, allowing it to withstand internal pressure and external forces.

Types of Dish Heads Based on Shape

Dish heads are classified based on their geometric shapes, and each type serves specific structural or functional needs.

Convex Heads:

• These heads feature an outwardly convex surface and are commonly used to ensure the structural integrity of containers that must withstand internal pressure.
• Examples include hemispherical heads, oval heads, disc heads, and unflanged spherical heads.
• Hemispherical heads are often used in high-pressure vessels because their shape can evenly distribute the internal pressure.
• Oval heads and disc heads can also be used depending on the design and pressure requirements.
• Some gas cylinders use convex inward heads, sometimes referred to as combined bottom heads, which enhance strength and safety by providing a more efficient load distribution.

Conical Heads:

• Conical heads feature a tapered shape and are typically used in applications where a smooth transition between cylindrical and conical shapes is necessary, such as in certain types of reactors and towers.
• These heads are particularly useful in handling both internal and external stresses due to their tapered nature.

Flat Heads:

• Flat heads are less common than convex or conical heads and are used in containers where internal pressure is relatively low or absent. They are simpler to manufacture and weld but are generally less effective at handling high internal pressure.

Combination Shapes:

• Some heads combine different geometric shapes to achieve specific design or structural benefits. These heads may combine convex and conical shapes, or use flat and convex elements, to meet the functional needs of the vessel.

Types of Welding for Dish Heads

Dish heads are typically welded to the cylindrical body of the container, and the welding methods can vary depending on the design and material requirements. The most common types of welding used for dish heads include:

1. Butt Welding Heads:

   • Butt welding involves joining the edge of the dish head directly to the cylindrical body without overlapping the edges. This creates a stronger joint, suitable for high-pressure applications.
   • Butt welds are often used for spherical, oval, and disc heads, as they provide a clean, smooth connection.

2. Socket Welding Heads:

   • In socket welding, the edge of the dish head is placed inside a matching socket on the cylindrical body, and the joint is welded around the circumference of the head and socket.
   • Socket welding is generally used for lower-pressure applications where a simpler and more cost-effective solution is acceptable.

(Titanium dish head )DIN28013:

Titanium alloys are categorized based on their composition and properties, and Grade 5 and Grade 7 are two commonly used grades of titanium. They each have unique characteristics, making them suitable for different applications.

Titanium Grade 5 (Ti-6Al-4V)

Titanium Grade 5, also known as Ti-6Al-4V, is the most commonly used titanium alloy. It consists of 90% titanium, 6% aluminum, and 4% vanadium, and is often referred to as the "workhorse" of the titanium alloy family because of its excellent combination of strength, corrosion resistance, and weldability. It is a beta-alpha alloy, which means it has both alpha and beta phases in its microstructure.

Properties of Titanium Grade 5:

• Strength: High strength-to-weight ratio, much stronger than pure titanium (Grade 2). Its tensile strength is around 900 MPa (130,000 psi) and can go up to 1,200 MPa (174,000 psi) depending on the heat treatment.
• Corrosion Resistance: Excellent resistance to a wide variety of corrosive environments, including sea water, chlorides, and many acidic and alkaline environments.
• Weight: About 60% of the weight of steel, which makes it useful in applications requiring a strong yet lightweight material.
• Temperature Resistance: Can withstand temperatures up to about 400°C (752°F) continuously and 600°C (1,112°F) for short periods.
• Fatigue Strength: Excellent fatigue resistance, making it suitable for cyclic loading conditions.
• Weldability: Good weldability, though it requires careful control of the welding process due to its susceptibility to contamination.

Applications of Titanium Grade 5:

• Aerospace: Aircraft structural components, airframes, turbine engines, fasteners.
• Medical: Prosthetics, dental implants, surgical instruments.
• Marine: Boat propellers, heat exchangers, seawater desalination equipment.
• Industrial: Pressure vessels, chemical reactors, high-strength industrial parts.

Advantages:

• High strength and toughness.
• Excellent corrosion resistance, especially in marine and aerospace applications.
• Widely available and relatively cost-effective compared to other titanium alloys.

Titanium Grade 7 (Ti-0.15Pd)

Titanium Grade 7 is essentially Grade 2 titanium (commercially pure titanium) with a small addition of 0.12-0.25% palladium (Pd), which is what gives it its distinct properties. The palladium content improves its resistance to corrosion, particularly in aggressive environments such as in the presence of chlorides, acids, or high temperatures.

Properties of Titanium Grade 7:

• Corrosion Resistance: Grade 7 offers superior corrosion resistance compared to other commercially pure titanium grades (like Grade 2). The addition of palladium gives it enhanced resistance to aggressive environments, such as acids and seawater, making it ideal for highly corrosive applications.
• Strength: Its tensile strength is lower than Grade 5, around 450-550 MPa (65,000-80,000 psi), but still offers good strength for many applications. It’s not as strong as Grade 5, but it provides superior corrosion resistance.
• Weight: As it is a form of commercially pure titanium, its weight is similar to other CP titanium grades, around 4.51 g/cm³ (about 45% lighter than steel).
• Formability: It has good formability and is easily welded and processed, though it is more susceptible to contamination during welding compared to higher-strength alloys.
• Temperature Resistance: Grade 7 titanium can withstand moderate temperatures, up to about 300°C (572°F) continuously. However, it is not as heat-resistant as Grade 5.

Applications of Titanium Grade 7:

• Chemical Processing: Used in reactors, heat exchangers, and piping where superior corrosion resistance is required, especially in acid and chloride environments.
• Marine Applications: Seawater desalination, offshore platforms, heat exchangers.
• Power Generation: Reactors, turbines, and other equipment exposed to corrosive fluids or environments.
• Medical: Used in surgical devices where high corrosion resistance is necessary, but it’s not typically used in load-bearing implants due to its lower strength.

Advantages:

• Superior Corrosion Resistance: Excellent in aggressive chemical environments, especially where chlorides and acids are present.
• Good Formability and Weldability: Easier to process than some higher-strength titanium alloys.
• Less Expensive Than Other High-Strength Alloys: While more expensive than Grade 2, Grade 7 is generally less costly than Grade 5 due to the absence of alloying elements like aluminum and vanadium.

Key Differences Between Titanium Grade 5 and Grade 7:

Production Procedures for Titanium Dish Heads

The production of titanium dish heads involves several critical steps to ensure the material meets the stringent requirements of strength, corrosion resistance, and surface finish. Here's a breakdown of the production process:

Initial Production of Titanium Plates or Clad Steel Plates

• Process: The production begins with the creation of titanium plates or clad steel plates, which will be formed into dish heads. These plates are either pure titanium or titanium alloys and may also involve cladding with other metals for enhanced properties.
• Inspection: The initial plates are inspected for any defects in the material such as cracks, inconsistencies, or impurities.

Cleaning and Grinding Plate Surface

• Process: The surfaces of the titanium plates are thoroughly cleaned to remove any oxidation, grease, or other contaminants. After cleaning, the surfaces are ground to a smooth finish to prepare for the forming process.

Coat Protection & Paint

• Process: A protective coating is applied to the plate to prevent any damage during the forming and handling process. In some cases, paint may be applied to provide further corrosion resistance or for aesthetic purposes.

Forming (Hot or Cold Forming)

• Process: The titanium plate is then formed into a dish shape, either through hot forming (at elevated temperatures to increase malleability) or cold forming (at room temperature). This process shapes the plate into the desired dish head configuration, which could be hemispherical, elliptical, or conical.

Preparation for Cutting & Grinding

• Process: After forming, the dish head is prepared for cutting. Excess material is trimmed, and the edges are ground to ensure a clean, uniform finish.

Pickling

• Process: Pickling involves immersing the titanium dish head in an acid bath to remove any scale, oxide layer, or contaminants formed during the forming and welding process. This step ensures the dish head has a clean surface for further processing.

UT & PT Testing

• Process: Ultrasonic Testing (UT) and Penetrant Testing (PT) are carried out to detect any internal or surface flaws, respectively. These non-destructive testing methods ensure the structural integrity of the titanium dish head.

Surface Polishing as Requested

• Process: If a specific surface finish is required (e.g., high-gloss or satin), polishing is done to achieve the desired appearance and smoothness. This also enhances the corrosion resistance of the surface.

Final Inspection

• Process: A final inspection is conducted to ensure that the titanium dish head meets all specified requirements, including dimensions, quality standards, and performance criteria. Any defects or discrepancies are addressed before moving to the next stage.

Packing

• Process: Once the titanium dish head passes all inspections, it is carefully packed for shipment. The packaging protects the dish heads from damage during transport, ensuring that they arrive in excellent condition at the installation site.

Applications of titanium Elliptical Heads:

The materials of Elliptical Heads: The dish head can be made of various materials according to the material of

the equipment body. For example, carbon steel (A3, 20#, Q235, Q345B, 16Mn, etc.), stainless steel (304, 321,

304L, 316, 316L, etc.), alloy steel (15Mo3 15CrMoV 35CrMoV 45CrMo), non-ferrous metals (aluminum, titanium,

copper, nickel and nickel alloy, etc.). The material must be the same as that of the device.We are specialized in

titanium hemispherical Heads.

Welding Types for Dish Heads

Dish heads are typically welded to the cylindrical body of a pressure vessel, and depending on the design, there are two common types of welding methods:

1. Butt Welding:

   • This is where the edges of the dish head and the cylindrical body are aligned and welded along their circumference. It ensures a smooth, flush connection that can withstand high internal pressures.

2. Socket Welding:

   • In this type, the head is fitted into a socket on the end of the cylinder, and the connection is made by welding the outer circumference of the socket. This method is more commonly used for smaller diameter vessels or low-pressure systems.

Specifications of Titanium Heads:

Chemical composition

Mechanical Property