Standard No.:	GB/T 45338-2025
English Name:	General principle for hot isostatic pressing densification
Chinese Name:	热等静压致密化处理通则
Professional Classification:	GB    National Standard
Source Content Issued by:	SAMR; SAC
Issued on:	2025-02-28
Implemented on:	2025-9-1
Status:	valid
Target Language:	English
File Format:	PDF
Word Count:	7000 words
Translation Price(USD):	210.0
Delivery:	via email in 1~3 business day

GB/T 45338-2025 General principle for hot isostatic pressing densification English, Anglais, Englisch, Inglés, えいご This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered. ICS 77.160 CCS H 70 National Standards of the People's Republic of China GB/T 45338-2025 General principle for hot isostatic pressing densification 热等静压致密化处理通则 (English Translation) Issue date: 2025⁃02⁃28 Implementation date: 2025⁃09⁃01 Issued by the State Administration for Market Regulation the Standardization Administration of the People's Republic of China Contents Foreword 1 Scope 2 Normative references 3 Terms and definitions 4 Environment 5 Equipment and instruments 6 Reagents or materials 7 Process 8 Quality control 9 File control 10 Safety protection General principle for hot isostatic pressing densification 1 Scope This document specifies the requirements for personnel, environment, equipment and instruments, process materials, process, quality control, document control, safety protection, etc. of densification treatment by hot isostatic pressing. This document is applicable for hot isostatic pressing densification treatment of parts prepared by casting, additive manufacturing, injection molding, injection molding and other processes with defects such as pores, looseness, shrinkage cavities, micro-cracks, and segregation. 2 Normative references The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB/T 394.1 Ethanol for industrial use GB/T 4842 Argon GB/T 6026 Acetone for industrial use GB/T 9452-2023 Test method for qualified work zone of heat treatment furnace GB 15735 Requirements for the safety and health in production process of metal heat treatment GB/T 30429 Industrial thermocouple assemblies 3 Terms and definitions There are no terms and definitions that need to be defined in this document. 4 Environment 4.1 The conditions of hot isostatic pressing plant shall comply with the requirements of GB 15735. 4.2 The hot isostatic pressing control and monitoring machine room should be isolated from the factory building. 5 Equipment and instruments 5.1 Equipment 5.1.1 The components, skeletons, heating elements and heat insulation parts of hot isostatic pressing equipment should be made of molybdenum (molybdenum wire or molybdenum strip), steel, nickel-based alloy or alumina, or graphite or graphite composite materials can be used as heating materials as needed. 5.1.2 Hot isostatic pressing equipment shall be equipped with temperature measurement and monitoring instruments, and each heating zone shall have an independent temperature control loop. The temperature uniformity and measurement period of hot isostatic pressing equipment shall not be lower than those in Chapter 5 of GB/T 9452-2023 IV Provisions for furnaces. 5.1.3 The maximum temperature and maximum working pressure of hot isostatic pressing equipment should meet the process requirements. 5.1.4 The heating speed and pressurization speed of hot isostatic pressing equipment should be adjustable. 5.2 Instruments 5.2.1 The accuracy of temperature measurement and temperature control instruments shall not be greater than ±1.1℃ or ±0.2% of the reading (whichever is the maximum value). 5.2.2 The allowable difference of indication accuracy of measuring and controlling pressure instruments is ±2% of the output range. 5.2.3 The accuracy of furnace temperature uniformity measurement is not greater than ±1.1°C or ±0.2% of the reading (whichever is the maximum). 5.2.4 The lower limit of the measurement range of the dew point meter is not greater than -70℃, the upper limit is not less than -30℃, and the accuracy is not greater than ±4℃. 5.3 Equipment qualification 5.3.1 Type/Qualification of high-pressure vessel 5.3.1.1 High-pressure vessels should have inert gas pressurization and internal heating cold wall functions. 5.3.1.2 Argon should be used as inert gas, which should comply with the provisions of GB/T 4842. When gases other than argon are used, it is determined by negotiation between the supplier and the demand parties. 5.3.2 Uniformity of temperature 5.3.2.1 When using conventional operating parameters for hot isostatic pressing of parts, the temperature uniformity measurement and inspection period of each hot isostatic pressing equipment shall not exceed 12 months. 5.3.2.2 For temperature uniformity measurement of new equipment and equipment after overhaul, the measurement period should be 3 months, and the measurement period can be adjusted to 6 months after the number of consecutive qualifications reaches 3 times; When the temperature uniformity measurement of normal use equipment is unqualified, the measurement period should be adjusted to 3 months. 5.3.2.3 Temperature uniformity measurement shall be repeated when: a) Modification, displacement or repair of equipment that may change the heating characteristics; b) During hot isostatic pressing, the recorded or indicated temperature exceeds the temperature tolerance requirement of ±15℃; c) The use temperature has been changed; d) The temperature-controlled thermocouple changes its position. 5.3.2.4 At least two thermocouples shall be placed in each heating zone of the high-pressure vessel of the hot isostatic pressing equipment, which shall be placed in the effective working area to determine the temperature uniformity. One thermocouple shall be connected to the recording instrument, and the other thermocouple shall be connected to the temperature control instrument (the temperature indicated by the thermocouple shall be recorded when necessary), and at least one of them shall have an alarm function and be connected to the alarm protection device. For hot isostatic pressing equipment with special requirements for furnace temperature control, more than two thermocouples should be placed in each heating area. 5.3.3 Measurement and control of temperature 5.3.3.1 A temperature measuring device (thermocouple) should be placed in the high-pressure vessel, and the temperature during the whole cycle should be recorded.