GB/T 3836.13-2021Explosive atmospheres - Part 13: Equipment repair, overhaul, reclamation and modification (English PDF)

4.2 User Rules

4.2.1 Explosion-proof certificate and engineering drawings

Equipment users should understand any relevant regulations related to regular inspections and verifications to ensure electrical equipment installed in explosive environments Is appropriate. The user should consider whether there are sufficient facilities and capabilities to undertake the user's repair or overhaul of such equipment, or whether it should be Contracted to professional repair and overhaul service providers. In addition, users should provide sufficient information to third-party service facilities and installers to perform Fulfill occupational health and safety obligations.

The user is responsible for obtaining the explosion-proof certificate of the equipment and other related documents (see 4.3.2.4) as part of the original factory equipment purchase agreement. part.

4.2.2 Records and work instructions

All relevant documents (see 4.3.2.4.1) obtained as part of the original purchase contract and records of any previous repairs, overhauls or modifications The recording should be kept in the verification file and provided to the repair unit.

Note: Generally, files and records are kept in the user's certificate file during the service life of the equipment.

In any possible situation, it is to maintain the user's benefit to inform the repair unit of the faults and characteristics of the repaired product and specific use information.

Benefits, for example, a motor is powered by a frequency converter.

Special requirements specified in the user manual and supplements to different standards, such as repair orders for improved protection levels, special environmental conditions, etc. You should pay attention.

The repairer should be informed to comply with any statutory requirements of the equipment explosion-proof certificate.

4.2.3 Repair equipment and reinstall

The repaired equipment should be reinstalled in accordance with GB/T 3836.15.

Note: GB/T 3836.15 requires that the cable or wiring system be checked before re-testing to ensure that they are intact and conform to the corresponding explosion-proof type of equipment Require.

4.2.4 Repair unit

Specific requirements in relevant national or regional regulations may apply to repair or overhaul operations.

Note: The user may need to confirm that the relevant repair unit can prove compliance with the relevant provisions of this document and any regulatory requirements.

4.3 Details of the repair organization

4.3.1 Legal requirements

The repair unit (which may be the manufacturer, user or third party) should understand any specific requirements in the relevant national or regional regulations. Can manage repair and maintenance operations.

4.3.2 Repair and overhaul

4.3.2.1 General

The repair organization shall operate an effective quality management system, which shall include the following detailed requirements.

Note: GB/T 19001 and GB/T 3836.21 provide additional guidance.

a) Each repair unit should designate a qualified person (person in charge) in the management organization (see Appendix A) to assume management responsibilities and management work, Ensure that the equipment meets the verification status agreed with the user after repair/overhaul. The appointed person shall have the corresponding explosion-proof standards and this Operational knowledge of the file.

b) A quality process plan should be developed, including appropriate inspection, diagnosis, testing and inspection procedures to ensure that repairs and overhauls meet the requirements of this document The functional and compliance requirements of other relevant standards, or Ex equipment explosion-proof qualification certificate and engineering drawings, so as to be able to confirm to users Applicability of reinstallation in hazardous locations is recognized.

c) The repair unit shall formulate procedures or work instructions for the inspection and repair of explosion-proof equipment.

d) The repair organization shall identify and record the scope of test and measurement capabilities and their use restrictions in the repair and overhaul of explosion-proof equipment.

e) The repair organization shall maintain the measurement equipment calibration system in accordance with national standards.

f) The repair unit should keep records, which should be clear and easy to read, and provide traceability of the measurement results to the calibration instrument for the specific measurement of the record. The records should be searchable within the specified storage period.

g) When carrying out dimensional and electrical measurements, the repair unit should record the values of "measurement before adjustment" and "measurement after calibration and adjustment" in the report. For future reference.

h) The repair organization shall develop an internal audit plan to illustrate the effectiveness of the repair organization in meeting the requirements of this document.

i) If a certain process may affect the integrity of an explosion-proof type, and the resulting integrity cannot be verified after repair, then This particular process is measured and monitored to prove compliance with the required parameters.

j) If testing is required, it should be carried out in accordance with the provisions of this document or other relevant standards, and sampling is not allowed.

k) When unqualified equipment is found, the repair organization should assess the risk to determine any remedial measures required. The repair organization should keep a record The record identifies the user and the full details of the remedial measures taken.

l) The repair unit should have sufficient repair and overhaul facilities, corresponding necessary equipment, trained personnel with required qualifications and authorization Personnel (see Appendix A) and the management organization that conducts work for specific types of explosion protection.

m) The repair organization should evaluate the condition of the equipment to be repaired, and agree with the user on the expected verification status and the required verification status after the equipment is repaired. Scope of repair work.

n) Any overhaul or repair should require the repair unit to confirm all explosion-proof requirements related to the explosion-proof type, so as to be able to verify compliance Compliance with engineering drawings or other relevant standards, including any specific conditions of use. This should include the Reasonably consider the omission of any tests included.

o) The assessment should be archived, and the relevant provisions of the appropriate explosion-proof type standard (this document) should be stated and included in the work report submitted to the user.

In the report. Such assessments should be carried out by the person in charge and supported by appropriate operators. The person in charge should only prove that he is capable The explosion-proof type of the force is evaluated.

p) Maintenance activities can only be carried out outside the repair organization where the quality management system allows the work to be completed in other locations, that is, through the generation of attachments. Add procedures and records to record inspections or repairs.

4.3.2.2 Qualification

The personnel directly involved in equipment repair or overhaul shall be qualified personnel or personnel under the supervision of qualified personnel. Is the qualification right? The same specific types of work.

Training and qualification assessment shall comply with the regulations in Appendix A.

4.3.2.3 Repair of components

When components of explosion-proof equipment are taken away from the site for maintenance, such as the rotor of the motor or The relevant explosion-proof type standard requires certain tests to be carried out. The repairer should record the details of the Form to notify users.

4.3.2.4 File

d) The maintenance records of the repaired parts, including.

1) Part identification;

4.3.2.4.1 General

The repair organization shall try to obtain all necessary information and data required for equipment repair or overhaul from the user or manufacturer. This should include Examine relevant explosion-proof type standards, engineering drawings, and information related to previous repairs, overhauls or modifications.

The repair organization shall keep and refer to copies of any relevant explosion-proof type standards that the repaired/overhauled equipment complies with.

The data required for repair or overhaul of engineering drawings and related drawings depends on the type of equipment being repaired and the type of explosion-proof. These data can Including but not limited to the following details.

a) Technical conditions;

b) drawings;

c) Related explosion-proof type;

d) Operating conditions (such as environment, power supply (whether inverter is used), grease, working system, etc.);

e) Disassembly and assembly instructions;

f) If specified, the equipment explosion-proof certificate and engineering drawings with special conditions of use are attached;

g) signs (including explosion-proof signs);

h) Suggested methods of equipment installation, operation, maintenance, repair or overhaul;

i) Spare parts catalog;

j) A summary of previous product repair history, including the information listed in 4.2.2. The above information can be adjusted.

Note: GB/T 3836.1 requires manufacturers to prepare instructions, including instructions on repairs.

4.3.2.4.2 Work records for users

After the repair work is completed, a work report should be submitted to the user to be included in the user's verification file. The work report should contain at least the following content.

a) Failure inspection status;

b) Description of repair and overhaul;

c) Replace and repair parts catalog;

d) The results of all inspections and tests (if necessary, the details are very useful to the unit that repairs in the future);

e) Inconsistent comparison with the results of the criteria that should be met;

f) A copy of the user contract or order; and

g) The repair qualification mark in Appendix B.

The storage time of repair/overhaul work records should be negotiated with the user, and the stored data should be managed to ensure easy retrieval.

For repairs that do not provide the equipment explosion-proof qualification certificate and engineering drawings described in 4.3.2.4.1, the repair report should include the following.

a) For the specific explosion-proof type that does not conform to the original manufacturer of the equipment, the repair is in accordance with the manufacturer's instruction manual or the appropriate explosion-proof standard A description of the requirements;

b) The repairer does not have sufficient evidence to prove that it is in full compliance with the equipment explosion-proof certificate and engineering drawings;

c) In the process of repair or overhaul, any special conditions of use are reviewed, and any relevant conditions of use are determined and considered. statement.

4.3.2.4.3 Records of the repair organization

The records kept by the repair organization are.

a) Copies of the old and new versions of the relevant technical standards.

b) The evaluation of the quality standard of the repair unit includes.

1) The quality assessment plan of the repair unit;

2) Test instrument calibration;

3) Personnel qualifications and training records;

4) Procurement control procedures;

5) User appeal handling;

6) Internal and (if necessary) external audit documents;

7) Management review;

8) Process control procedures;

9) Manufacturer's drawing details.

c) Work records include.

1) Steps to obtain an explosion-proof certificate and engineering drawings;

2) The mechanical inspection records that meet the relevant standards, including the traceability of the instrument used and the pass/fail criteria;

3) Identification of defects;

4) Electrical test records before and after repair, including the traceability of the instrument used and the pass/fail criteria;

5) Explosion-proof certificate of replacement component;

6) Repair procedures for the repaired parts;

7) Evaluation record of the decision taken by the person in charge;

8) Mechanical inspection records during and after assembly;

9) Work records of the repair unit;

10) Records of replacement parts manufactured by the repair unit.

2) The name of the repair unit;

3) Specific reasons for repair;

4) The various options considered (such as welding, metal spraying);

5) Technical parameters, such as bond strength;

6) Reasons for choosing the repair process;

7) Consumables used and storage methods;

8) Basic materials;

9) The repair process considered in the manufacturer's product instruction manual;

10) The procedures used;

11) The identity and qualifications of the operators;

12) The inspection procedures used, such as ultrasound, color penetration, X-ray;

13) Maintenance and calibration of the automatic system;

14) Details of the size that is different from the explosion-proof certificate or the original part;

15) Repair drawings including removal and replacement of materials;

16) Date of restoration.

These records should be kept for at least 10 years or as agreed by the user.

4.3.2.5 Spare parts

4.3.2.5.1 General

Generally, new parts should be purchased from the manufacturer, and the repair unit should ensure that the spare parts used are compatible with the explosion-proof equipment being repaired. And equipment Sex-related spare parts shall be specified by the manufacturer, equipment standards or relevant explosion-proof certificates and engineering drawings.

If the parts cannot be supplied by the original manufacturer, the repair shop can manufacture or purchase replacement parts through subcontractors, provided that.

a) The complete specification of the component is available;

b) The quality plan of the repair unit allows.

Records of replacement parts should be kept and provided to users.

4.3.2.5.2 Fasteners

If replacement fasteners are used, they should be the same type, material, diameter, pitch, length, and tensile strength specified by the original equipment. Tight If the tensile strength of the firmware is uncertain, the equipment manufacturer should be consulted.

Unless specified in the original explosion-proof certificate documents and engineering drawings or the explosion-proof type standard on which the equipment is manufactured, bolt heads, screw heads and No flat washers or lock washers should be placed under the nuts.

If the shield is installed initially, it should be kept firmly connected.

4.3.2.5.3 Sealing parts

Seals required by equipment technical specifications and explosion-proof certificates or engineering drawings should only be replaced with special spare parts specified in the spare parts list.

The devices installed on the equipment that show the intervention of the third party (such as protective seals) are different from the requirements of the explosion-proof certificate and engineering drawings. Does not fall within the scope of this article.

4.3.2.6 Marks after equipment repair

Existing labels should be checked to ensure that they are safe and easy to read.

The equipment shall be provided with signs identifying the repair or overhaul and the repair unit. The mark after repair of the equipment shall comply with the provisions of Appendix B.

The logo can be added to a single sign board. In the following cases, it is necessary to modify or remove the original sign or add a sign.

a) If, after repair, overhaul or modification, the equipment still complies with the restrictions specified in this document, the explosion-proof standards and engineering It is not advisable to remove the label, and the repair symbol "R" should be written in the square (see Appendix B).

b) If after repair, overhaul or modification, the equipment still complies with the restrictions specified in this document and the explosion-proof standards adopted during manufacturing, But it does not necessarily conform to the engineering drawing, usually the label should not be removed, and the repair symbol "R" should be written in the inverted triangle (see Appendix B).

c) After the equipment has been repaired, overhauled, altered or modified, if there is a change and no longer meets the explosion-proof standard or engineering drawing, the label should be removed The "Ex" mark and the issuer's mark on the board, unless a supplementary certificate is obtained.

d) If you do not know the manufacturing standards of the previously certified equipment, the requirements of this document and the current version of the relevant explosion-proof standards should be applied.

The assessment should be carried out by a person who has the ability to assess explosion-proof equipment to verify whether the repair unit meets the relevant safety level, or No release the equipment. The person performing the assessment must not be connected to the repair unit and should be part of the accreditation body, which is qualified Check and test explosion-proof equipment.

e) For the old class II and class III equipment, if there is no engineering drawing, or the nameplate is missing or unavailable, the user can refer to GB/T 3836.16 Carry out suitability assessment. A qualified person then creates the replacement label. The repair organization shall not conduct applicability assessment.

4.3.3 Repair

4.3.3.1 General

When the repair process includes repair, in addition to the implementation of the repair provisions of 4.3.2, the following also applies.

Repairs that do not affect the explosion-proof type are not the subject of discussion in 4.3.3. Good engineering practices should be used to repair such parts to make them suitable use.

If the repair procedure will affect the size or other overall aspects of the explosion-proof type that are different from the relevant engineering drawings provided, it is a modification.

If there is any uncertainty about the impact of the expected repair procedure on the explosion-proof type, the manufacturer or certificate issuer's advice should be sought.

It is also necessary to conduct tests to verify that the repair procedure is acceptable.

4.3.3.2 Exceptions

The following parts are considered not to be repaired, so they are not within the scope of this document. Examples of parts that cannot be repaired include.

a) Parts made of glass, plastic or other materials with unstable dimensions;

b) fasteners; and

c) The manufacturer states that parts that cannot be repaired, such as encapsulated components.

4.3.3.3 Requirements

4.3.3.3.1 General

The repair work should be carried out by trained and familiar with the process using the best process operating procedures (see Appendix A). Repair technical Operators, such as welding or metal spraying, should conduct preliminary and regular practical skill tests in accordance with the provisions of A.5. The restoration shall be documented in accordance with 4.3.2.4.3.

If the repair is not carried out by the user, a copy of the record shall be provided to the user.

If any proprietary process is used, the initiator's instructions for such processes should be followed.

4.3.3.3.2 Responsibility

If the repair unit signs a contract to subcontract equipment repairs to other units, the repair unit shall bear the responsibility for such repairs.

4.3.3.4 Repair process

4.3.3.4.1 General

The following points can be used in the repair process of explosion-proof equipment.

It should be admitted that not all methods are suitable for all types of explosion protection. Therefore, the corresponding clauses of this document give a detailed description.

The amount of metal removal should be minimized, and the damaged part that requires repair is just removed, and the thickness of the coating is in line with the technology used The minimum value specified.

Remove not more than 2% of the metal thickness or 0.5mm of the metal thickness (whichever is greater) for metal spraying, and not more than 20% of the metal thickness for welding, should not cause obvious damage to the strength of the part. The removal of larger thickness materials should be done with the manufacturer After proper negotiation, or if the manufacturer does not already exist, it will be calculated. The repair organization shall ensure that after the equipment is repaired After completion, the equipment will reach a fully usable state and meet the requirements of corresponding explosion-proof standards. The repair organization shall record the above compliance and keep it in Work file.

4.3.3.4.2 Metal spraying method

When the degree of wear or damage of the repaired part before spraying, plus the machining necessary for the repair of the part, the total impact on the strength is not excessive When the safety limit is exceeded, this technique should be used. The metal layer sprayed to increase rigidity should not be included when calculating the strength. Of course, spray on metal Machining before coating operation may cause stress rise, which will further weaken the mechanical strength of the component.

When the line speed exceeds 90m/s, the metal spraying method is not recommended.

4.3.3.4.3 Electroplating method

As long as the repaired parts still have sufficient mechanical strength, this process can be used. The chromium plating and nickel plating procedures are respectively described in GB/T 11379 and It is stipulated in GB/T 12332.

4.3.3.4.4 Setting method

When the degree of wear or damage of the repaired part before spraying, plus the machining necessary for the repair of the part, the total impact on the strength is not excessive When the safety limit is exceeded, this technique should be used. When calculating the strength, it is not appropriate to add the rigidity of the casing into account.

4.3.3.4.5 Brazing and welding methods

Unless the brazing process used can ensure proper penetration and welding of the solder and the mother body, and after aging treatment, it can prevent deformation and eliminate stress.

And there is no pores, so this process method can be used. It should be considered that brazing and welding will increase the temperature of the component and cause the possible extension of fatigue cracks. This document and GB/T 5185 approve the following welding techniques.

a) MMA. manual metal arc welding;

b) MIG. MIG welding;

c) TIG. Tungsten inert gas shielded welding;

d) Sub-Arc. Metal inert gas shielded welding under the flux layer;

e) Welding wire welding; and

f) Any other welding technique described in GB/T 5185 that uses flux or inert gas to shield the welding metal. Other repair techniques The technique can only be used after consulting the manufacturer or explosion-proof inspection agency.

4.3.3.4.6 Metal pressing method

For castings with considerable thickness, nickel alloy can be used to fill the gaps and then compact the technology for cold repair.

4.3.3.4.7 Screw holes of fasteners

All restored threaded holes shall meet the requirements of relevant explosion-proof standards. Depending on the type of explosion-proof, it can be repaired by one of the following methods Damaged threads, these threads failed the GO-NOGO test.

Note: ISO and other standards have further information on thread forms.

a) Increase the drilling size and re-tapping;

b) Enlarge the drilling size, re-tapping, and install special threaded inserts that have passed the corresponding tensile test specified by the manufacturer;

c) Increase the drilling size, block the screw holes, re-drill and tap;

d) Enlarge the drilling size and tap, insert a solid threaded plug, and re-machine (as required);

e) Block the screw hole, re-drill and tap it in another position; or

f) Plug welding, re-drill and tap.

Repair threaded holes for fasteners should meet one of the following requirements.

a) Use special threaded inserts to repair the threaded holes, and carry out the test in accordance with the test method of the threaded insert manufacturer;

b) For other repaired threads that meet the torque test, the torque is equal to the bolt torque and should not exceed 80% of the bolt tensile strength, and the thread The minimum engagement is 1.5 times the nominal diameter of the bolt; or

c) The enclosure should be subjected to an overpressure test. The plug should be firmly fixed to avoid accidental disassembly.

4.3.3.4.8 Re-machining method

Re-machining of worn or damaged surfaces can only be carried out under the following conditions (if applicable). According to the equivalent equipment data, the strength of the components The degree should not exceed the safety limit.

a) As long as the integrity of the enclosure is maintained; and

b) Reach the required surface roughness.

4.3.4 Changes and modifications

4.3.4.1 Changes

The main role of the repair organization is to maintain or restore the equipment to its original certified state. The repair organization cannot assume the role of the manufacturer And assemble new equipment.

When the repair process includes changes, in addition to the repair provisions of 4.3.2, the following provisions also apply.

a) The equipment should not be modified, except as permitted by the explosion-proof certificate and engineering drawings; and

b) If the repair unit does not have engineering drawings, the suggested changes shall be confirmed by the manufacturer in written form as permitted by the explosion-proof certificate.

Row. Chapters 5 to 15 give detailed instructions on the changes to different explosion-proof types.

4.3.4.2 Modification

The user should be notified in writing. If a modification is proposed and the equipment does not meet the engineering drawing or equipment certification standards, the user should provide Written instructions on how to proceed. If modified, without additional assessment, the equipment will no longer be suitable for use in explosive environments. If proceed If the modification is made, but no additional assessment has been made, the label should be removed or changed to clearly indicate that the equipment does not comply with the explosion-proof certificate. In addition, to the user The report should clearly state the design characteristics of the transformation, and the unassessed equipment is no longer suitable for use in explosion-hazardous locations. The report should not be compliant prove.

If the label is removed, it should be negotiated with the user and strive to maintain the traceability of the product, see 4.3.2.6.

4.3.5 Temporary repair

Temporary repairs can only be carried out when the explosion protection safety is guaranteed or other appropriate measures are taken before the equipment is fully restored to keep the equipment in Continue to operate in the short term. Therefore, certain temporary repair procedures may not be permitted. It is advisable to make any temporary The repair meets the complete repair standard.

According to good engineering practice, temporary repairs should only be completed on site and negotiated with the user, manufacturer or repair unit.

Temporary repairs should be fully recorded and added to the verification file and equipment repair records. Good engineering practices should be followed and used with equipment Household consultation.

4.3.6 Motor

4.3.6.1 General

The repair organization should follow the general industrial requirements in GB/T 21205, which include ensuring that IEC 60034 (all parts) covers The procedures required for satisfactory overhaul and repair of motors of all types and sizes are suitable for motors to be installed in non-hazardous locations. This document The requirements in is a supplement to the requirements of GB/T 21205 for explosion-proof equipment installed in hazardous locations.