551 The role of the AI Authorized Inspector
This is a system of third party inspection to ensure that manufacturers of ASME vessels follow the ASME code rules. In the simplest situation, a boiler manufacturer and the boiler purchaser are the first two parties, and an Authorized Inspector AI is the independent third party. It is the function of the AI to verify that the manufacturer complies with the code. Who are they An AI is defined by ASME Section I PG-91 as an inspector employed by a state or municipality of the United States, a...
522 The vessel dimensional check
Practically, the dimensional check can be done either before or after the hydrostatic test see Fig. 5.1 . Any strains or distortions that do occur will be small, and difficult to detect by simple measurements methods. Dimensional checking can be done using a steel tape measure, with the use of a long steel straightedge and large inside or outside callipers for some dimensions. Dimensional tolerances for pressure vessels tend to be quite wide. There is a technical standard DIN 8570 that gives...
Fig 41 Vessel to PD 5500 Cat 1
Plate thickness is limited to 40 mm for carbon steel groups M0 and M1 30 mm for C-Mn steel group M2 40 mm for austenitic steel Specified materials are the same as for Cat 1 vessels - see PD 5500 Tables 2.3 NDT requirements NDT extent and technique
622Valve technical standards
Technical standards in common use for cast steel valves are valve design and shell wall thickness API 600 pressure-temperature rating ASME ANSI B16.34 face end dimensions ASME ANSI B16.10 flange dimensions ASME ANSI B16.5 and B16.47 inspection and testing API 598. The ASME ANSI standard B16.34 is a valve standard used in conjunction with the ASME codes on boilers and power piping in ASME design installations and, separately, as a valve standard in itself. The standard is relevant to flanged,...
97 NDT vessel code applications
Pressure vessel and other pressure equipment codes vary in the way that they address both the extent of NDT required and the acceptance criteria that are applied to the results. Tables 9.5 and 9.6 summarize NDT requirements given in the vessel codes covered in chapter 4. Note that these are indicative requirements only code inquiry cases may exist that can clarify or even amend these requirements. Table 9.5 NDT requirements pressure vessel codes quick reference 100 RT or UT on type A joints...
Table 43 PD 5500 Cat 1 Key points
It is unusual for boiler drums not to be specified as fully compliant with Cat 1 requirements. Remember that independent survey and certification is mandatory for full PD 5500 compliance. If 'non-specified' materials are used, do a full check on the material properties. PD 5500 Section 2 specifies the checks that are required for materials to be permissible. Check that all pressure-retaining material is positively identified and is traceable to its source. As a guide, high-alloy steels should...
Table 418 Air receivers to BS 5169 key points
BS 5169 requires that 'competent supervision' is required for class I receivers, but does not specify full independent inspection. In practice it is common for air receivers to be considered as having equivalent 'statutory status' to BS 5500 vessels, hence they are normally subject to independent survey and certification. It is rare to see any type of 'partial code compliance' specified for these air receivers. For class I receivers, BS 1449 and BS 4360 plate materials are not permitted....
Fig 114 Pressure equipment classification and conformity assessment Source DTI
Engineers' Guide to Pressure Equipment Production classifications explosive, flammable, toxic, or oxidizing Group 2 All other fluids Exceptionally, vessels intended to contain an unstable gas and falling within categories I or I on the basis of Chart 1 must be classified in category III Exceptionally, vessels intended to contain an unstable gas and falling within categories I or I on the basis of Chart 1 must be classified in category III Fig. 11.5 PED - the nine classification charts. Source...
46 The ASME vessel codes
The ASME code comprises the following sections ASME Section The ASME code comprises the following sections ASME Section Rules for construction of power boilers Rules for construction of nuclear power plant components Rules for construction of heating boilers Rules for care and operation of heating boilers Rules for construction of pressure vessels Fibre-reinforced plastic pressure vessels Rules for in-service inspection of nuclear power plant components The ASME Boiler and Pressure Vessel Code,...
Table 44 PD 5500 Cat 2 Key points
As with Cat 1 vessels it is unusual for Cat 2 pressure vessels not to be specified as fully compliant with code requirements. Independent survey and certification is mandatory. PD 5500 Cat 2 vessels have limits placed on maximum plate thickness -this limits the design pressure. Material traceability requirements are the same as for Cat 1 vessels. Note that permanent weld backing-strips are allowed for Cat 2 vessels. Check that they are of the correct 'compatible' material. Alignment tolerances...
Table 42 PD 5500 a summary
Manufacturer purchaser agreement Section 1.4 places the responsibility for code compliance firmly on the manufacturer. Look at Section 1.1 - it confirms that PD 5500 applies only to vessels built under independent survey. Section 1.4 specifies that code compliance is documented by the use of 'Form X' - this is issued by the manufacturer and countersigned by The Inspecting Authority the 'third party . Table 1.5 lists approximately 50 points for separate agreement. Vessel design is covered by...
322 Safety first corrosion allowance and welded joint efficiency
Corrosion occurring over the life of a vessel is catered for by a corrosion allowance, c, the design value of which depends upon the vessel duty and the corrosiveness of its contents. As an example, a design criterion of c 1 mm is typical for air receivers in which condensation of air moisture is expected. Most vessel codes use the principle that, when dimensions in any formula refer to a corrodable surface, then the dimensions inserted into the formula are those at the end of the vessel's...
23 Pressure equipment symbols
Pressure equipment symbols are in regular use in schematic drawings and Process and Instrumentation Diagrams PIDs . There are many variations based on BS, ISO, and American standards. Figures 2.1-2.4 show some commonly used types. Table 2.3 and Figs 2.5 and 2.6 show symbols for typical pressure equipment-related instrumentation. Fig. 2.1 Vessel symbols. Courtesy MS Visio Covered tank Gas holder Storage sphere Gas cylinder Horizontal vessel Autoclave Fig. 2.1 Vessel symbols. Courtesy MS Visio...
14 The KKS power plant classification system
The KKS Kraftwerk Kennzeichensystem is a completely generic designation system that identifies every system, component, and location within a plant, using a string of letters and numbers. It is used for power and process plant across many industry sectors. The KKS designations are commonly used on equipment spares inventories, Process and Instrumentation Diagrams PIDs , and plant labelling. From the pressure equipment viewpoint, the most important function is that related to process...