API STD 625-2010 pdf free download

API STD 625-2010 pdf free download.Tank Systems for Refrigerated Liquefied Gas Storage.
8.1 Introduction Tank system construction in accordance with this standard consists of various sub activities such as design, procurement, fabrication, construction, and testing for all subsystems such as the foundation, tanks, piping, insulation, electrical, instrumentation systems, etc. A quality management system shall be utilized to ensure that the work performed meets quality requirements. Comments: 1) Quality management systems consist of quality control (QC) and quality assurance (QA) activities. 2) QC is a system of routine activities developed to measure and control the quality of the work as it is being performed. The QC system is designed to provide routine and consistent checks to ensure correctness and completeness and identify corrective responses. 3) QA consists of a series of systematic planned activities implemented in a quality system so that quality requirements are met. QA includes procedures for the implementation of QC. 4) Documents such as ISO 9001 and API Specification Q1 provide guidance for establishing QA and QC plans. 8.2 NDE, Testing, and Tolerances 8.2.1 Nondestructive examination (NDE) activities during tank system construction shall be performed to ensure that the quality requirements of the work are met. 8.2.2 Testing, such as hydrostatic and pneumatic tests, loop checks of the electrical work, and foundation level measurement, is mandated by construction standards to ensure construction integrity. 8.2.3 Tolerances are imposed by API 620 or ACI 376 as applicable such that design considerations are not violated.
9.1 System Design The insulation system shall be designed to: a) not fail under the specified or calculated static and dynamic loads; b) maintain product boil-off at or below the specified limit at the specified climatic conditions; c) maintain components (such as those of an outer tank) at or above their minimum design temperature; d) minimize condensation and icing; e) prevent soil freezing (in combination with the tank foundation heating system for foundations on grade); f) prevent ingress of moisture (in combination with other tank components); g) be purged (loose fill and blanket insulation) during commissioning and decommissioning. 9.2 General Requirements 9.2.1 Tests of materials are required to ensure that their properties (thermal conductivity, strength, density, etc.) are adequate. See 9.8 for specifications. 9.2.2 A detailed testing, installation and inspection plan shall be submitted by the Tank System Contractor to the Purchaser. 9.2.3 Insulation shall be protected, particularly from moisture, during shipment, storage, installation, tank hydrotest and while in service. 9.2.4 For liquid oxygen tanks, insulation shall be noncombustible. 9.3 Load Bearing Bottom and Thermal Corner Protection (TCP) Insulation 9.3.1 System Design The insulation shall be designed for static and dynamic compressive and shear loads. These loads include weight, earthquake, and tank movement due to commissioning and decommissioning and filling and emptying. 9.3.2 Materials Permitted materials for bottom and TCP insulation include brittle materials (cellular glass), materials subject to creep but with closed cells (polyvinyl chloride, etc.) and, for ring beams, high load bearing materials. For concrete ring beams, refer to ACI 376. 9.3.3 Detailed Design 9.3.3.1 Structural design of insulation shall be based on allowable stress or limit state design. For limit state design, follow EN 14620–4 Annex C.
9.3.3.3 For brittle materials with open surface cells, an interleaving material shall be applied to develop the compressive strength of the material. System tests shall have established the effectiveness of the material used and the bearing capacity shall be reduced by that effectiveness. Interleaving materials other than asphalt Type III or IV shall be tested or shall have been previously tested to include the following. a) Blocks shall be selected from the same production run. b) Halves of a minimum of ten blocks shall be used for the control tests and the other halves for the interleaving material. c) Control tests shall be per ASTM C240 to duplicate the tests basis of the material manufacturer. d) Tests with the interleaving material shall be per ASTM C240 except for sample preparation. e) Each compressive strength grade shall be tested separately. 9.3.3.4 For materials subject to creep, the permissible load shall be established in accordance with EN 14620-4, Section 6.3.2.2.2. 9.3.3.5 The thermal design of the ring beam and any underlying insulation shall prevent temperatures from going below the minimum design temperature of the bottom or liner under the ring beam. 9.3.4 Installation 9.3.4.1 Insulation joints shall be staggered with minimum gaps. 9.3.4.2 Insulation shall be installed over a leveling layer of concrete or sand and topped with a layer of concrete, sand, or other material. 9.3.4.2.1 Sand, if used, shall be clean, free flowing, non-plastic, free of organic matter, have a maximum chloride content of 500 ppm, and no greater than 5 % shall pass a number 200 sieve. 9.3.4.2.2 Sand, if used, shall also have a maximum installed moisture content of 5 % by weight (measured immediately prior to covering with insulation or bottom plate).