Types of Nozzles in Pressure Vessels.pptx

This PPT describes the various types of nozzles uses in the pressure vessels. It discusses the calculation process.

1. CH18704 PROCESS EQUIPMENT DESIGN Nozzles and It’s types

2. INTRODUCTION A vessel nozzle is an opening in the vessel through which fluid enters or exits the vessel . The Nozzle, in general, projects from the vessel’s surface and ends with a means of joining (flanged or welded) piping or equipment. To carry the normal process or operation of the vessel these nozzle connections are required. The main functions of a pressure vessel nozzle opening can be any of the following

3. To allow the content to move into the vessel or away from the vessel to help further processing of the fluid. To allow the insertion of instrument items. To allow for inspection or access to internal parts (Manholes).

4. PARTS OF A VESSEL NOZZLE A vessel nozzle consists of three parts A flange Connection (for flanged connection with pipe) Nozzle Neck part and Reinforcement (in case required)

5. RADIAL AND NON-RADIAL NOZZLES TYPES OF VESSEL NOZZLE: From the orientation perspective, pressure vessel nozzles can be classified into two groups : Radial nozzles The axis of the radial nozzle is perpendicular to the surface of the vessel, and also passes through the center of the vessel. Non-radial nozzles If the axis of the nozzle is not perpendicular to the vessel, and/or it does not pass through the center of the vessel, it is termed a non-radial nozzle. A common subset of non-radial nozzles is “hillside” nozzle. This term is usually applied to those nozzles on formed heads which are located away from the center and whose axis is parallel to the axis of the vessel.

6. ATTACHMENT OF NOZZLES Regardless of type of reinforcement, there are two ways to attach the nozzle: Set-in nozzles –  the diameter of the opening in the shell coincides with the outer diameter of the neck. In this case the nozzle gets through the shell/head. Set-on nozzles – the diameter of the opening in the shell coincides with the inner diameter of the neck. The nozzle is supported by the shell / head.

7. Normally, the manufacturers would like to use the set-on type nozzles; there are less bevels to prepare and there is less thickness of the weld. On the other hand, customers usually require just the opposite. Set-on nozzles are generally acceptable when: Pressure vessel thickness is high Thickness of nozzle neck is considerably smaller than the vessel where it will be attached Vessel is not subject to cyclic condition throughput its life When no special services are considered.

8. CLASSIFICATION OF NOZZLES BY CONSTRUCTION Conventional nozzles These are the nozzles that are built up from a pipe and a flange; and if required, a reinforcing element. The flange can be either slip-on, welding neck or lap joint as shown below. Occasionally, socket weld and threaded flanges are also used.

9. Screwed couplings These are fittings with threads on the inside. If threads are present at both the ends, they are called full couplings; if they are present at only end, they are called half couplings . The unthreaded end of half coupling is welded to the vessel. Two common thicknesses for screwed couplings are 3000 and 6000 pounds. 3000-pound coupling generally correspond to schedule 80 thickness, and 6000-pound couplings generally correspond to schedule 160 thicknesses.

10. Studding outlets They provide a compact design with inherent reinforcement and offer distinct advantages to fabricators and designers. The low profile provides for the smallest projection of the bolted connection where clearance may be a factor. The studding outlets can be supplied with optional contoured bottom and/or a lip for butt-weld connection to the vessel . Long weld necks Long weld neck flanges are one-piece construction that replace a standard welding neck and pipe weld combination. The lack of necessary weld connection is its defining feature. The standard long weld neck is provided with uniform pipe thickness. If extra thickness is required for reinforcement purposes, a heavy barrel weld neck or a variable thickness weld neck can be provided.

11. DESIGN OF PRESSURE VESSEL NOZZEL For the design of Pressure Vessel nozzles,  various codes and standards  are available. However, the most widely used internationally recognized ASME BPVC Section VIII by the American Society of Mechanical Engineers (ASME). Other pressure vessel codes and standards that are occasionally used are: Europe: EN-13445 United Kingdom: British Standards BS PD 5500 France: CODAP China: GB-150 Germany: A. D. Merkblatt Code Nozzle design basically means three parts: Deciding the nozzle size or nozzle opening Designing and Selecting Nozzle thickness and Calculating the reinforcement requirement based on pressure and external loads . The design of pressure vessel nozzles is done following equations mentioned in ASME Section VIII, Div. 1 UG 36 to UG 45.