This standard specifies the definition, marking, technical requirements, test methods, inspection rules and packaging requirements of warp knitted mesh made of polyethylene monofilaments with a diameter of 0.18mm to 0.22mm. This standard is applicable to diamond mesh, unshaped or shaped polyethylene warp knitted mesh. SC/T 5021-2002 Polyethylene mesh warp knitting SC/T5021-2002 standard download decompression password: www.bzxz.net

ICS.65.150
Aquatic Industry Standard of the People's Republic of China
SC/T 5021—2002
Polyethylene netting
Warp knitting type
Polyethylene netting-Raschel type2002-11-05 Issued
2002-12-20 Implementation
Issued by the Ministry of Agriculture of the People's Republic of China
This standard is proposed by the Fisheries Bureau of the Ministry of Agriculture.
This standard is under the jurisdiction of the Fishing Gear Material Sub-Technical Committee of the National Technical Committee for Aquatic Standardization, SC/T5021—2002
The drafting units of this standard are: Lehai Fisheries Research Institute of the Chinese Academy of Fishery Sciences, Quality Supervision and Inspection and Testing Center of Rope and Net Products of the Ministry of Agriculture. Guangdong Zhanjiang Economic and Technological Development Zone Aquatic Net Factory. The main drafters of this standard are: Guo Yiping, Tang Zhenming, Ma Haixing, Mao Liniu, Mi Lianfang, Wu Shuigang, Chen Liqiu. 1 Scope
Polyethylene mesh
Warp knitting
SC/T 5021-2002
This standard specifies the definition, marking technical requirements, test methods, inspection rules and packaging requirements for warp knitted mesh made of polyethylene monofilaments with a diameter of 0.18mm~.22mm. This standard applies to diamond mesh, unshaped or shaped polyethylene warp knitted mesh. 2 Normative references
The clauses in the following documents become the clauses recommended by this standard through non-standard references. For any dated referenced document, all subsequent amendments (excluding errata) or revisions are not applicable to this standard. However, parties to an agreement based on this standard are encouraged to study whether the latest versions of these documents can be used. For any undated document, the latest version shall apply to this standard: GR/T4925—1985 Test method for breaking strength and breaking elongation of composite fiber fishing net 6 Method for measuring mesh size of fishing net
G3/E6964—1986
3 Definitions
The following terms and definitions apply to this standard. 3.1
Raschel netting
A net composed of two adjacent nets, each forming a loop along the longitudinal direction of the net and alternately connected with each other, also known as a set knitted net. The mesh of the net is usually a knitted chain structure with loops and wefts. 3.2
Joop
The most basic component unit of knitted fabrics, in the shape of a space curve, consisting of two loops, a needle loop and a sinker loop (or extension line). 3.3
rows
rows in a knitted fabric before the loops are connected transversely 3.4
stitchdensity
number of threads in a knitted fabric within a specified length. 3.5
design
a post-processing method to make the mesh reach a predetermined rigid size under the action of external stretching or heating. 3.6
longitudinal direction of a warp knitted mesh, N-dirertion of raschel netting, the square of the longest axis of the mesh.
closedmesh
a mesh in which four yarns in adjacent meshes are entangled and cannot be stretched. 3.8
Fluat
A line that is crossed should be connected to the longitudinal row of the loop. 1
SC/T 5021- 2002
Nominal ply
The sum of three times the number of loop yarns in the warp shrinkage mesh and the number of weft yarns. 4 Marking
The marking is composed of the mesh material, single filament diameter, nominal number of strands, mesh size and other elements and the number of this standard. Example:
The single filament true diameter is 0.20 TI, the nominal number of strands is 5, and the mesh size is 20 InII. The marking of the ethylene warp knitted mesh is: PE 0. 20X 5-20 SC/T 5021
5 Technical requirements
The nominal number of strands, mesh size range and weaving density of polyethylene warp knitted mesh shall comply with the provisions of Table 1. Table 1 Nominal number of strands, mesh size range and weaving density of mesh Nominal number of strands
Net size range/um
70~:28
10--30
12--40
15--60
5.2 The net size deviation of polyethylene warp knitted mesh shall comply with the provisions of Table 2. Table 2 Mesh size allowable deviation
Mesh size/mm
i1--·20
Unshaped/(%》
Weaving length/(row/10mm)
After shaping/()
53The strength performance of polyethylene warp knitted mesh shall be in accordance with the following provisions according to the diameter of polyethylene monofilament used for unshaped or shaped mesh and netting.
5.3. 1 The monofilament diameter is 0.20 1. The longitudinal breaking strength of the unshaped polyethylene warp knitted mesh shall be greater than or equal to the requirements of Table 3, and the coefficient of variation shall be less than or equal to the requirements of Table 3.
Number of nominal strands
Table 3 Coefficient of variation of longitudinal breaking strength of unshaped polyethylene warp knitted mesh
SC/T5021—2002
Breaking strength/N
5.3.2 The diameter of the single wire is 0.20mm, and the breaking strength of the mesh of the shaped polyethylene warp knitted mesh shall be greater than or equal to the requirements of Table 4, and the coefficient of variation shall be less than or equal to the requirements of Table 4.
Table 4 Mesh breaking strength requirements of shaped polyethylene warp knitted mesh Nominal number of strands||tt || Large coefficient of variation)
Breaking strength/N
5.3.3 Measure the diameter of polyethylene monofilament in the mesh. The strength index value of the mesh of this specification is obtained by multiplying the index value of the corresponding nominal number of strands in Table 3 or Table 4 by the coefficient shown in Table 5. The effective digit is 3. The coefficient of variation is required to remain unchanged: Table 5 Breaking strength coefficient of polyethylene monofilament warp knitted mesh of various diameters. True diameter of monofilament/mml
The mesh should be knocked with polyethylene mesh wire whose total number of strands is slightly larger than the nominal number of strands of the warp knitted mesh. 5.4
Repair by weaving a single dead knot mesh,
5.5 The appearance resistance of the polyethylene warp knitted mesh should be less than or equal to the requirements of Table 6. SC/T 5021—2002
Repair length at each location
Note 1: The repair length at each location is the cumulative length of the mesh when it is closed. Table 6 Appearance requirements
Measurement unit
Note 2: The repair rate is the ratio of the number of mesh repairs to the total number of days of the mesh. The percentage values ​​of joint and missing strands listed in the table only refer to the mesh with a nominal number of strands. For meshes with 7 strands, 9 strands, 10 strands, 12 strands, and 15 strands, the allowable error white fraction should be multiplied by the value listed in the table (number of strands/5). For example, the number of joint months for a 7-strand mesh is ≤0.05×7/5. The rest is analogous. 6 Test method
6.1 The atmospheric conditions in the mesh strength test room are a temperature of 20C±2, a relative humidity of 60%~70%, and the sample conditioning time is more than 6h.
6.2 The measurement method of mesh weaving density, observe the mesh with a fabric density microscope, read the number of coils within the scale line at a length of 20mm, and calculate its average value.
6.3 The measurement method of mesh size is in accordance with GB/T69641986: the nominal number of strands with a pre-tension of 2 times is the number of roots, and the rated deadweight of a single wire with a length of 250m.
6.4 The test method of mesh H breaking strength and mesh longitudinal breaking strength is in accordance with GB/T4925--1985. 6-5 The method of measuring the diameter of the single wire used in the mesh is to measure the diameter at its point with a micrometer, and then rotate it about the axis for about 90 degrees and measure it for times, and read the measured values ​​one by one respectively, calculate the average value and take two decimal places. 7 Inspection rules
7.1 Batch
100 pieces of mesh of the same specification are a batch, and less than 100 pieces are also a batch. 7.2 Inspection classification
Inspection is divided into factory inspection and type inspection
7.3 Inspection items
Products are inspected in batches, and the inspection items for factory inspection are Articles 5.2.5.3 and 5.5 of this standard. The inspection items for type inspection are all filled in Chapter 5 of this standard. Factory inspection should be carried out when the product is delivered. When the product is transferred to another factory for production, when there are major changes in raw materials and process formulas, when there is a big difference between the factory inspection and the last type inspection, type inspection should be carried out if there are provisions in the contract and the quality supervision agency requires it.
7.4 Sampling
Five meshes are randomly selected from each batch of products, and the number of samples after appearance inspection meets the requirements of Table 7. Inspection itemswww.bzxz.net
Mesh size
Weaving density
Table 7 Number of samples for inspection of two batches of products
Mesh breaking strength (mesh after shaping)
Mesh breaking strength (mesh without shaping)
Single wire diameter
7.5 Determination and measurement
Sincerity of sample number
SC/15021—2002
Products are inspected in batches. If one of the physical and mechanical properties is unqualified or two of the appearance indicators are unqualified, the batch of products shall be judged as unqualified.
8 Marking, packaging, transportation, storage
8.1 Marking
The mesh shall be accompanied by a product certificate. Indicate the name and detailed address of the manufacturer, trademark, product name, specification, production period or batch number, quality and inspection mark.
8.2 Packaging
One or several meshes of the same specification can be packed into one piece, and it is advisable to have an outer packaging of appropriate materials. The specifications, quantity and net weight shall be marked on the outside of each package.
8.3 Transportation
During transportation and loading and unloading, do not drag or hook to avoid damaging the packaging. 8.4 Storage
The mesh should be stored in a clean and dry warehouse away from heat sources.
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.