Standard No.:	SH/T 3021-2013
English Name:	Code for the design of seal and purge of instrument and piping for petrochemical industry
Chinese Name:	石油化工仪表及管道隔离和吹洗设计规范
Chinese Classification:	P72    Petrochemical and chemical industry engineering
Professional Classification:	SH    Professional Standard - Petrochemical
Issued by:	MIIT
Issued on:	2013-10-17
Implemented on:	2014-3-1
Status:	valid
Superseding:	SH 3021-2001 Code for the design of seal and purge of instrument and piping for petrochemical industry
Language:	English
File Format:	PDF
Word Count:	5000 words
Price(USD):	120.0
Delivery:	via email in 1 business day

1 Scope This specification specifies the minimum requirements for the design of sealing and purging of instrument measurement and tubing for automatic control engineering in petrochemical industry. This specification is applicable to the engineering design of the sealing and purging of instrument measurement and tubing for petroleum refining, petrochemical industry or the construction, expansion and renovation of plants for making fuels and chemical products by taking coal as the raw materials. This specification is not applicable to positive pressure ventilation system adopted for corrosion protection or in areas subject to explosion hazards. 2 Normative references The following referenced documents are indispensable for the application of this specification. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB 150.3-2011 Pressure vessels - Part 3: Design 3 Terms and definitions For the purpose of this specification, the following terms and definitions apply. 3.1 diaphragm sealing sealing method in which diaphragm is used to prevent the direct contact between the measured medium and the sensor element of the instrument 3.2 liquid sealing sealing method that prevents the direct contact between the measured medium and the sensor element of the instrument by filling the sealing vessel with sealing liquid

Foreword i 1 Scope 2 Normative references 3 Terms and definitions 4 Instrument sealing 4.1 Scope of service 4.2 Diaphragm sealing 4.3 Liquid sealing 5 Instrument purging 5.1 Scope of service 5.2 Characteristics of purging fluid 5.3 Design of purging gas system 5.4 Design of the flushing liquid system 6 Design of the purging set 6.1 Purge set composition 6.2 Design of purging set Annex A (Informative) Corrosion resistance for diaphragm material in corrosive media at different temperature and concentration Annex B (Informative) Property and application of sealing liquid Annex C (Informative) Typical drawing of purging set connection Annex D (Informative) Hook-up drawing for purging set tubing Bibliography Explanation of wording in this specification