1.0 purpose

In order to ensure the stability of the welding material quality of the company, the testing normative documents are put forward.

2.0 scope

Applicable to the inspection standards of welding materials in the process of acceptance, storage and use.

3.0 operation requirements

3. 1 acceptance

The acceptance content of welding materials shall be determined according to the manufacturing regulations, types and actual needs of welding products.

3. 1. 1 packaging inspection

Check whether the welding material package meets the requirements of relevant standards, whether it is in good condition, and whether it is damaged or damp. 3. 1.2 Inspection of quality certification documents

For welding materials with quality certificate, check whether the information provided by the quality certificate is complete and meets the specified requirements.

3. 1.3 covered electrode quality inspection +0.3. 1 sampling

When each batch of covered electrode enters the factory for inspection, representative samples shall be taken from at least 3 parts on average according to the required quantity. 3. 1.3.2 test method

Check the appearance of samples by visual inspection or 5 times magnifying glass, and select 10 pieces for size measurement. 3. 1.3.3 Welding quality requirements.

A) Coated covered electrode Coating: The coating should be evenly and tightly wrapped around the welding core, and the covered electrode surface of the coating should be smooth, free of defects such as rust, scale, cracks, bubbles, impurities and peeling.

B) covered electrode exposed core of the coating: the coating should have sufficient strength, the coating at the arc initiation end should be chamfered, and the end face of the welding core should be exposed to ensure easy arc initiation. Covered electrode bare core shall meet the following requirements:

The length of (1) low-hydrogen coated covered electrode along the exposed core length should not be greater than 2/3 of the core diameter or 1.6mm (whichever is smaller).

② For other types of covered electrode, the length of the cored wire exposed along the length direction should not be greater than 2/3 or 2.4 mm of the diameter of the flux-cored wire (whichever is smaller).

The exposed core of coated covered electrode with different diameters along the circumference should not exceed half of the circumference. C) covered electrode eccentricity:

(1) covered electrode with diameter ≤ 2.5mm and eccentricity ≤7%.

(2) covered electrode with a diameter of 3.2mm and 4.0mm, eccentricity should not be greater than 5% (3) covered electrode with a diameter of ≥5.0mm or more, eccentricity should not be greater than 4% eccentricity calculation:

Covered electrode eccentricity

=

Where t 1- the maximum thickness of covered electrode coating+the diameter of flux-cored wire;

T2 —— Minimum thickness of coating on the same section+core diameter.

D) The diameter and length of covered electrode shall meet the provisions of the corresponding covered electrode standards GB/T5 1 17, GB/T5 1 18, GB/T983 and GB/T984 respectively.

E) Packaging in covered electrode: covered electrode will pack every 2.5kg, 5kg or 10kg lot number or corresponding lot number. This package should be sealed, which can ensure that the covered covered electrode will not deteriorate and be damaged when stored in a dry warehouse for at least one year;

The following contents shall be marked on the outside of each package and box: standard number, covered electrode model and covered electrode brand, manufacturer's name and trademark, specification and net weight or quantity, batch number and inspection number;

For each batch of covered electrode, the manufacturer shall issue a quality certificate according to the actual inspection results for the supplier's inquiry; The manufacturer shall provide a copy of the inspection when requested by the user.

F) Marking: at least one covered electrode model or trademark is printed on the coating near the clamping end of covered electrode. The font should be printed conspicuously, and there should be a strong contrast between the font color and the coating, so that it can be clearly distinguished before and after the normal welding operation.

3. 1.3.4 composition and performance test

A) The performance indexes of covered electrode type or model used for the first time must be tested and inspected, and the test methods and inspection results should comply with the provisions of relevant standards.

B) The mechanical properties, X-ray flaw detection, corrosion resistance, diffused hydrogen content and water content of T-joints and deposited metals in covered electrode do not need to be tested, analyzed and inspected in every batch when they enter the factory in covered electrode.

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C) When changing suppliers or adopting new covered electrode types or models for new technology, the above performance indicators must be tested and inspected, and the test methods and test results must conform to the provisions of relevant standards.

3. 1.4 welding wire quality inspection

The chemical composition of steel wire for fusion welding and gas shielded welding shall comply with the provisions of relevant standards. The surface quality of steel wire should be visually inspected, and the surface of steel wire should be smooth, without visible cracks, folds, scars, scales, corrosion and other harmful defects. There should be no cracks, pits, corrosion and coating peeling on the copper-plated steel wire. The diameter of steel wire for fusion welding and its allowable deviation shall conform to the following table 1:

Table 1 Diameter and allowable deviation of fusion welding steel wire and gas shielded welding steel wire

Steel wire bundles (discs) shall be neat, and shall not be scattered or "∞" shaped. 3. 1.5 flux inspection

Flux is usually used for submerged arc welding of carbon steel. Flux should meet the requirements of relevant standards. 3. 1.5. 1 sampling

Flux used in various tests should be dispersed and extracted. If the flux is dispersed, each batch of flux should have no less than 6 sampling points. If the flux is packed in packaging bags, a certain amount of flux should be extracted from each 10 bag for each batch of flux. The total flux taken out from each batch of flux shall not be less than 10kg. Mix the extracted fluxes, stir them carefully and evenly, and then take out 5kg flux as the trial welding flux for welding the mechanical properties test board by quartering method, and take another 5kg flux as the test flux for testing other projects.

3. 1.5.2 test method a) flux particle size test method

Take out no less than 100g of flux from the test flux by quartering method as particle size test. The equilibrium sensitivity of the sample used is less than 65438±0mg.

When testing ordinary particle size flow, the flow passing through the screen and the flow not passing through the 8-mesh screen are respectively weighed; When inspecting the fine-grained flux, the flux passing through the 60-mesh screen and the flux failing to pass through the 14-mesh screen are respectively weighed. These fluxes have become flux with particle size exceeding the standard.

Calculate the percentage content of flux with particle size exceeding the standard according to the following formula:

Flux with particle size exceeding the standard (%) =

Where m is the weight (g) of flux with particle size exceeding the standard;

—Total weight of flux (g).

× 100%

If the first granularity test is unqualified, the above process should be repeated twice. Only when the two tests are qualified, the particle size of this batch of flux is considered qualified.

Flux that has undergone repeated particle size inspection should be re-screened, and then inspected according to the above method. B) Detection method of flux moisture content

Take out a large amount of flux of 100g from the inspection flux by quartering method for water content inspection. The sensitivity of the weighing balance used shall not exceed 1mg.

Put the flux into a furnace with the temperature of 150℃+ 10℃ and dry it for 2 hours. After being taken out of the furnace, it is immediately put into a dryer and cooled to room temperature. Calculate the moisture content of flux according to the following formula:

Water content of flux (%)=× 100%

formula

—Flux weight before drying (g);

M- weight of flux after drying (g).

If the water content test fails for the first time, the test shall be repeated according to the method of b). C) Inspection method of flux mechanical inclusions

When mechanical inclusions are inspected, the flux of not less than 1000g shall be taken out from the inspected flux by the quartering method. The sensitivity of the weighing balance used shall not exceed 1mg. Select mechanical inclusions by visual inspection and weigh them. Calculate the percentage content of mechanical inclusions according to the following formula.