1 Scope
This document specifies the classification and marking of copper and copper alloy seamless tubes for air conditioning and refrigeration system valves (hereinafter referred to as "tubes"), technical requirements, test methods, inspection rules, marking, packaging, transport, storage, accompanying documentation and order form content.
This document applies to seamless copper and copper alloy tubes for air conditioning and refrigeration system valves (e.g. four-way reversing valves, stop valves, solenoid valves, check valves, etc.).
2 Normative references
The contents of the following documents constitute the essential provisions of this document through the normative references in the text. Among them, note the date of the cited documents, only the date of the corresponding version applicable to this document; do not note the date of the cited documents, the latest version (including all the revision of the list) applicable to this document.
GB/T 242 Test methods for flaring of metal tubes
GB/T 2828.1 Sampling procedures for counting and inspection ﹑ Part 1: Lot-by-lot inspection sampling plan for retrieval by Acceptance Quality Limit (AQL) GB/T 5121 (all parts) Methods of chemical analysis for copper and copper alloys
GB/T 5231 Grades and chemical composition of processed copper and copper alloys
3 Terminology and definitions
There are no terms and definitions that need to be defined in this document.
4 Classification and labelling
4.1 Product classification
The grade, code, state, type and specification of the tube should be in accordance with the provisions of Table 1.
4.2 Product marking
Product marking is indicated by the product name, the number of this document, the grade (or code), the state and the order of the specification.
5 Technical requirements
5.1 Chemical composition
The chemical composition of the pipe should be consistent with the provisions of the corresponding grades in GB/T 5231, of which lead (Pb) ≤ 0.03%, cadmium (Cd) ≤ 0.01%. 5.2 Dimensions and their allowable deviations
5.2.1: Outline dimensions and their permissible deviations
The dimensions of the tubes and their permissible deviations shall conform to the provisions of Table 2 and Table 3.
5.2.2 Length and its permissible deviation
The allowable deviation of the length of a straight pipe of fixed or double length shall be in accordance with the provisions of Table 4. The length of the pipe shall be fixed or doubled within the indeterminate range, and the length of the pipe shall be doubled by adding a saw cut of 5 mm to the unit length.
5.2.3 Slope of cut
The end of the pipe should be sawn flat (the section of the inspection port may be retained). The slope of the cut shall be in accordance with Table 5, provided that the length of the cut does not exceed its permissible deviation.
5.2.4 Roundness
The roundness of straight pipes in the drawn (H58) and lightly drawn (H55) condition shall conform to the provisions of Table 6.
5.2.5 Straightness
The straightness of straight pipes in the drawn (H58) and lightly drawn (H55) condition shall be in accordance with the provisions of Table 7.
5.3 Mechanical properties
The room temperature mechanical properties of the pipe shall be in accordance with the provisions of Table 8.
5.4 Process performance
Soft annealed (O60) state and lightly drawn (H55) state of the pipe can be flaring test, using 60 ° punch cone, flaring rate of not less than 30%, after flaring specimens should not produce cracks or fissures visible to the naked eye.
5.5 Grain size
The average grain size of the pipe shall conform to the provisions of Table 9.
5.6 Residual stress
Brass tubes should be treated to eliminate residual stresses. The H65 grade pipe should be subjected to a residual stress test after the residual stress has been removed. There should be no cracks visible to the naked eye in the pipe after the residual stress test.
5.7 Eddy Current Flaw Detection
Tubes shall be subjected to eddy current inspection and straight tubes that do not give an alarm signal on the eddy current inspection equipment signalling device shall be considered as conforming to this document. Coils shall be marked with a dark mark not less than 300 mm long at the location of the defect and the number of defects allowed shall be determined by agreement between the supplier and the customer. Standard manual defects shall be through holes, the diameter of which shall be in accordance with Table 4 of 6.4 of GB/T 5248-2016.
5.8 Surface quality
5.8.1 The surface of the pipe shall be smooth, clean and free from defects affecting its use. 5.8.2 The internal surface roughness of the pipe shall be no greater than Ra0.4.
6 Test methods
6.1 Chemical composition
The chemical composition of the pipe shall be analyzed according to GB/T 5121 (all parts) or YS/T 482 or YS/T 483, and the arbitration shall be carried out according to GB/T 5121 (all parts).
6.2 Dimensions and their permissible deviations
The dimensions of the pipe and its permissible deviations should be measured in accordance with GB/T 26303.1; where the straightness of H65 pipe length less than 400 mm is checked using a stopper.
6.3 Mechanical properties
The tensile test of the pipe shall be carried out in accordance with GB/T 34505-2017, and the tensile specimen of the pipe with outer diameter not more than 30 mm shall be carried out in accordance with GB/T 34505-2017 for full section specimen; the pipe with outer diameter more than 30 mm shall be carried out in accordance with GB/T 34505-2017 for Sl specimen.
6.4 Process performance
The process performance of the pipe is carried out according to the provisions of GB/T 242.
6.5 Grain size
The grain size inspection of the pipe is carried out in accordance with the provisions of YS/T 347.
6.6 Residual stress
The residual stress test of the pipe is carried out in accordance with the provisions of GB/T10567.2.
6.7 Eddy current flaw detection
The eddy current flaw detection method for pipes is carried out in accordance with the provisions of GB/T 5248-2016.
6.8 Surface quality
6.8.1 The surface quality of the pipe is inspected visually.
6.8.2 The internal surface roughness of the pipe is recommended to be inspected using a surface roughness meter, or a surface roughness standard block can be used for comparison.
7 Inspection rules
7.1 Inspection and acceptance
7.1.1 The pipe shall be inspected by the supplier or a third party to ensure that the product quality is in accordance with the provisions of this document and the order form.
7.1.2 The demand side may inspect the products received from the Sinc according to the provisions of this document. If the inspection results do not conform to the provisions of this document and the order form, they shall be put forward to the supplier in writing and solved by consultation between the supplier and the demand side. Objections concerning surface quality and dimensional deviation shall be raised within one month from the date of receipt of the product. Disagreements concerning other properties shall be raised within 3 months from the date of receipt of the product. If arbitration is required, the supply and demand sides shall jointly take samples or negotiate on the demand side.
7.2 Group batches
Pipes shall be submitted in batches for acceptance, each batch shall consist of pipes of the same grade, condition and specification. The weight of the pipe shall be not more than 5 000 kg per batch.
7.3 Inspection
7.3.1 The inspection of the product shall be divided into factory inspection and type inspection, and the inspection items shall conform to the provisions of Table 10.
7.3.2 Any of the following cases, the type test shall be carried out:
a) new products or old products transferred to the plant's prototype identification
b) products of raw materials, processes have a large change, may affect the performance of the product
c) after the product is discontinued, resume production;
d) factory test results and the last type test have a large difference
e) two consecutive years without type testing
f) when the demand side requirements (specified in the order form);
g) when the national quality supervision agencies to carry out the type test requirements.
7.4 Sampling and sample preparation
Sampling of pipes shall be in accordance with the provisions of Table 1l. The sampling method shall be carried out in accordance with the provisions of YS/T 668, and the sample preparation of process performance shall be carried out in accordance with the provisions of YS/T 815.
7.5 Determination of test results
The value of the test result is modified according to the provisions of GB/T 8170, and the modified value comparison method is used to determine. Test results are determined according to the provisions of Table 12.
8 signs, packaging, transport, storage and accompanying documents
8.1 Marking
8.1.1 Product markings
8.2 Packaging, transport and storage
8.2.1 The packaging, transport and storage of the pipe shall be in accordance with the provisions of GB/T 8888.
8.2.2 Special requirements for packaging shall be determined by mutual agreement between supply and demand.
8.3 Accompanying documents
Each batch of products shall be accompanied by documentation which shall include, in addition to information on the supplier, product information, the document number, the date of delivery or the date of packaging, the following.
9 Order form content
The demander may, according to its own needs, order the products listed in this document in the order form, listing the following content:
a) Product name;
b) Brand number;
c) Status
d) type;
e) Specification
f) Net weight or number of rods (plates)
g) Grain size (if required by the customer)
h) Number of this document;
i) Other.
1 Scope
2 Normative references
3 Terminology and definitions
4 Classification and labelling
5 Technical requirements
6 Test methods
7 Inspection rules
8 signs, packaging, transport, storage and accompanying documents
9 Order form content
