GB/T 34587-2017Technical requirements for steel refrigerated container repair (English PDF)

3.1 Steel refrigerated container

A refrigerated container equipped with a refrigeration compressor unit. The main frame and outer panels of this container are made of steel.

3.2 Original components

The original structural components of the steel refrigerated container.

5.1 Pre-repair inspection of refrigeration units

5.1.1 Basic requirements

5.1.1.1 Before inspecting electrical wiring or unplugging the refrigerator's cable, the power supply switch of the refrigeration unit shall be disconnected. While the refrigeration unit is powered on, the condenser fan and evaporator fan shall not be touched.

5.1.1.2 When testing the insulation resistance of electrical equipment with a megohmmeter, the power supply switch of the refrigeration unit shall be disconnected first; the electronic equipment such as the microcomputer controller and electronic temperature recorder shall be removed.

5.1.1.3 When performing a pre-trip inspection (PTI) of the refrigeration unit, the pre-operation inspection shall be performed first, followed by the operational inspection.

5.1.1.4 When an automatic PTI inspection detects a fault, after identifying and repairing

2) Temperature recorder equipped with a "31-day quartz clock". After the quartz clock power is turned on, the recording pen can continuously record for more than 31 days on the recording paper in real time;

3) Temperature recorder whose recording paper rotation is controlled by a clock signal output from a microcomputer controller. After inputting a 31-day time signal to the microcomputer controller into a computer (inputting once or several times as required by the instruction manual), the temperature recorder reads the data from the microcomputer controller; the recording pen can continuously record for 31 days on the recording paper;

h) Requirements for cleaning, moisture protection, fixing, preventing arbitrary disassembly of the electronic circuit board are given in 5.3.4 i) ~ o).

6.1 Basic requirements

6.1.1 When performing electric welding on the container, the power supply switch of the refrigeration unit shall be disconnected first; electronic equipment such as the microcomputer controller and electronic temperature recorder shall be removed.

6.1.2 Repair work on the refrigerated container (such as sandblasting, painting, foaming, etc.) shall be carried out, in accordance with relevant environmental protection provisions; waste polyurethane foam containing CFCs shall be disposed of.

6.2 Container inspection

6.2.1 Container deformation inspection

6.2.1.1 Corner fitting positioning shall comply with the requirements of GB/T 1413.

6.2.1.2 Repair shall be carried out if any of the following deformations occur in the external components of the container.

a) The external components of the container deform outwards beyond the allowable external limit of the container deformation (measured from the plane containing the corresponding corner fitting), see Appendix B;

b) Except for the corner posts and the outer bottom plate, other external components of the container deform in any direction (including outwards) exceeding 35 mm (measured from the plane before deformation of the deformed surface).

6.2.1.3 Repair is required for any of the following deformations of the internal

6.3 Container repair

6.3.1 After repair, the external dimensions and tolerances of the container shall conform to Appendix A.

6.3.2 After repair, the internal dimensions of the container shall be restored to the original design dimensions. Internal dimensions shall be measured from the inner surface of the internal partitions, walls, top air ducts, bottom air ducts.

6.3.3 After repair, the dimensions and installation positions of all components shall be restored to the original design dimensions and installation positions.

6.3.4 The following provisions shall be observed during container repair; tests shall be conducted as specified by the quality supervision personnel when necessary.

a) The container strength shall meet the requirements of GB/T 7392;

b) The water tightness, air tightness, heat leakage, refrigeration performance of the refrigerator shall meet the requirements of GB/T 7392.

6.3.5 When repairing the container, materials of the same type as the original components or materials with performance indicators no lower than the original components shall be used.

6.3.6 During container welding, the butt joint gap shall not exceed 2 mm. The weld height and width shall be consistent with the original weld. The weld surface shall be uniform and dense, with a smooth transition to the original component, free from defects such as cracks, weld beads, pinholes, arc craters, undercut, with sufficient fusion depth. Spatter on both sides of the weld shall be removed.

6.3.7 High-strength insulating tape shall be used to separate metals of different materials (such as aluminum and iron), to prevent electrochemical corrosion.

6.3.8 When welding on steel plates with foam, sealant, adhesive, or paint coatings, safety precautions shall be taken.

6.3.9 Labels on refrigerated containers shall comply with the requirements of GB/T 1836, with correct positioning, clear lettering, firm and flat adhesion, free from wrinkles, bubbles, skewing, cracks, inversion.

6.3.10 Before painting the steel refrigerated container, remove impurities adhering to the painting surface, such as dirt, welding slag, spatter, moisture, oil stains, rust spots.

Clean the painting surface and consider sandblasting to improve surface roughness.

6.3.11 Sandblasting of the steel refrigerated container shall meet the following requirements.

a) The cleanliness of the sandblasted metal surface shall reach Sa2.5 level;

b) The surface roughness of the sandblasted surface shall be within the range of 25 µm ~ 50 µm;

c) The total metal thickness remaining after sandblasting shall be greater than or equal to 90% of the original metal thickness;

d) After sandblasting, remove all abrasive and residual dirt; perform a light leakage inspection, to determine if there are any holes or damage caused by sandblasting.

Remove surface dust using compressed air blowing or vacuuming; keep the surface clean;

e) Paint shall be applied to the sandblasted metal surface within 1 hour;

f) The sandblasting operation of the container shall comply with relevant environmental protection and labor protection provisions.

6.3.12 The paint coating of steel refrigerated containers shall meet the following requirements.

a) The new paint shall be chemically compatible with the original residual paint on the container components (some containers have markings of the original topcoat model on the inside right side near the door) and with the new primer, intermediate coat, topcoat. Choose compatible paints from the same manufacturer with guaranteed quality whenever possible;

b) The paint film thickness shall meet the minimum dry film thickness recommended by the paint manufacturer (primer, intermediate coat, topcoat);

c) For stainless steel and corrosion-resistant aluminum plates in the container components, determine whether painting is required based on the original component requirements;

d) All metal surfaces in contact with the insulation foam shall be coated with an adhesive 15 µm ~ 25 µm thick as required by 6.3.22.3.3;

e) For metal surfaces such as beams and columns made of weather-resistant high-strength steel (CORTEN), apply an anti-corrosion epoxy zinc-rich primer (or thermally sprayed zinc) and allow it to dry slightly, before applying an epoxy intermediate primer and topcoat;

f) Surfaces of exterior door panels, outer side panels, exterior top panels, beams (excluding the lower part of the lower side beam), columns made of stainless steel (MGSS) can be directly sprayed with epoxy intermediate primer and topcoat;

g) The bottom components of the container made of stainless steel (MGSS) […]