GB/T 36702.1-2018 English PDFUS$439.00 · In stock
Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email. GB/T 36702.1-2018: Irrigation equipment -- Safety devices for chemigation -- Part 1: Small plastics valves for chemigation Status: Valid
Basic dataStandard ID: GB/T 36702.1-2018 (GB/T36702.1-2018)Description (Translated English): Irrigation equipment -- Safety devices for chemigation -- Part 1: Small plastics valves for chemigation Sector / Industry: National Standard (Recommended) Classification of Chinese Standard: B91 Classification of International Standard: 65.060.35 Word Count Estimation: 22,262 Date of Issue: 2018-09-17 Date of Implementation: 2019-04-01 Issuing agency(ies): State Administration for Market Regulation, China National Standardization Administration GB/T 36702.1-2018: Irrigation equipment -- Safety devices for chemigation -- Part 1: Small plastics valves for chemigation---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order. Irrigation equipment - Safety devices for chemigation - Part 1. Small plastics valves for chemigation ICS 65.060.35 B91 National Standards of People's Republic of China Irrigation equipment chemical irrigation safety device Part 1. Small plastic valves for chemical irrigation Part 1.Smalplasticsvalvesforchemigation (ISO 13693-1.2013, IDT) Published on.2018-09-17 Implementation of.2019-04-01 State market supervision and administration China National Standardization Administration issued ForewordGB/T 36702 "Safety Device for Irrigation Equipment Chemical Irrigation" consists of the following parts. --- Part 1. Small plastic valves for chemical irrigation; --- Part 2. Chemical irrigation valve assemblies from DN75(3) to DN350(14). This part is the first part of GB/T 36702. This part is drafted in accordance with the rules given in GB/T 1.1-2009. This section uses the translation method equivalent to ISO 13693-1.2013 "Safety devices for irrigation of chemical equipment - Part 1. Chemical Small plastic valve for irrigation. The documents of our country that have a consistent correspondence with the international documents referenced in this part are as follows. ---GB/T 7306-2000 55° sealed pipe thread (eqvISO 7-1.1994) --- GB/T 18691.1-2011 Agricultural irrigation equipment - Part 1 . General requirements (ISO 9635-1.2006, MOD) This section has made the following editorial changes. --- Added a figure for unit conversion in Appendix A. This part was proposed by the China Machinery Industry Federation. This part is under the jurisdiction of the National Agricultural Machinery Standardization Technical Committee (SAC/TC201). This section was drafted by. China Academy of Agricultural Mechanization Sciences, Jiangsu University Fluid Machinery Engineering Technology Research Center, Zhejiang Rongyagong Trade Co., Ltd. The main drafters of this section. Zhang Xiansheng, Wang Yang, Ning Chao, Zhao Liwei, Lu Huaxiong. Irrigation equipment chemical irrigation safety device Part 1. Small plastic valves for chemical irrigation1 ScopeThis part of GB/T 36702 specifies the general requirements and test methods for small plastic valves for chemical irrigation (hereinafter referred to as "devices"). The device is used in irrigation tubing systems that may contain certain fertilizers or chemicals of common types and concentrations in agriculture. This section applies to controllable safety devices with a reduced pressure zone (RPZ) (also known as backflow preventers). The device is used to prevent drinking when drinking upstream When the water distribution system pressure is lower than the downstream system pressure, the irrigation water flows back into the upstream drinking water distribution system due to back suction or back pressure. This section applies to the nominal size not greater than DN50, the nominal pressure is PN10, and can be corrected or adjusted in the following cases. Working device. ---The pressure is below 1MPa; --- The amount of pressure change is not more than 1MPa; --- Long-term work in a temperature not greater than 45 ° C, the temperature at 65 ° C for 1 h.2 Normative referencesThe following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article. Pieces. For undated references, the latest edition (including all amendments) applies to this document. ISO 7-1 - Threaded pipe threads - Part 1. Dimensions, tolerances and markings (Pipethreadswherepressure-tight Jointsaremadeonthethreads-Part 1. Dimensions, tolerancesanddesignation) Agricultural irrigation equipment - Irrigation valves - Part 1. General requirements (Agriculturalirrigationequipment- Irrigationvalves-Part 1.Generalrequirements)3 Terms and definitionsThe following terms and definitions as defined in ISO 9635-1 apply to this document. 3.1 Controllable safety device with reduced pressure zone controlablesafetydevicewithareducedpressurezone;controlable safetydevicewithRPZ A two-action check valve (3.7) is fitted with a hydraulically controlled mechanical independent pressure relief valve between the two check valves. 3.2 Reflux backflow A flow that is opposite to the normal flow direction. 3.3 Back sucking back-siphonage Reflux due to system pressure reduction to below atmospheric pressure (3.2). 3.4 Back pressure backpressure The pressure in the downstream of the piping system that is higher than the supply pressure, which can cause the water to flow in the opposite direction of the normal water flow. 3.5 Nominal pressure nominalpressure PN Chemical Irrigation (3.6) The maximum static water pressure required to operate close to the upstream with a small plastic valve. 3.6 Chemical irrigation Various chemicals are applied through the irrigation system. 3.7 Check valve checkvalve The water flow can be automatically opened in a specific direction, and the valve that prevents the water from flowing in the opposite direction can be automatically closed.4 classificationThe nominal size and connection dimensions of the valve are to comply with the requirements of Table 1. Table 1 Thread and flange connection dimensions of the unit Nominal size DN Mm 8 10 15 20 25 32 40 50 Nominal diameter of threaded connection (ISO 7-1) In 1/4 3/8 1/2 3/4 1 11⁄ 11⁄ 2 Nominal diameter of flange connection Mm - - - - - - 40 505 logoThe device shall identify the following. a) model number; b) nominal size (DN) (see Table 1); c) nominal pressure (PN); d) connection type; e) plastic material type (universal); f) Perform the numbering of this section.6 materialsIn the technical and sales specifications of the device, the manufacturer shall state the type of material used to manufacture the device. The device should be corrosion resistant. The material from which the device is made should be capable of being applied to chemicals that are routinely applied to irrigation systems. If the device is likely to come into contact with drinking water, the device and the materials used to make it should comply with national standards for drinking water.7 Design requirements7.1 General requirements The design features of the device (see Figure 1) should meet the following requirements. a) 3 pressure zones (upstream zone, intermediate zone and downstream zone), under static and flow conditions, the upstream zone pressure P1 is greater than the intermediate zone pressure Pi, the intermediate zone pressure Pi is greater than the downstream zone pressure P2; b) P1-Pi >14kPa; c) when P1-Pi≤14kPa, the intermediate pressure zone is open to the atmosphere; d) when P1≤14kPa, the intermediate pressure zone is not connected to the atmosphere; e) minimum set pressure relief flow (reflow rate); f) In each pressure zone, the unconnected and sealed state of the safety device (sealing, discharge valve) can be confirmed. Description. 1---upstream pressure (P1) zone; 2---intermediate pressure (Pi) zone; 3---downstream pressure (P2) zone; 4---upstream check valve; 5---downstream check valve; 6---pressure relief valve; 7---pressure tapping hole; 8---Funnel. a Upstream. b Downstream. Figure 1 Design schematic The internal components of the unit should be accessible for inspection, repair and replacement. It should also be able to be inspected, repaired and more after the unit is installed. change. Internal components should be replaceable without removing the device, and will not be confused (it is impossible to install components such as seals, diaphragms, springs, etc. phenomenon). It is not enough to just use the logo. The spring seat should be fixed and not adjustable. The operation of the internal components of the unit should only be controlled by the water pressure of the water supply network. Additional control devices (electric, pneumatic, etc.) may not adversely affect the backflow protection function. The unit shall be installed horizontally, except when the manufacturer declares that it can be installed vertically. The test should be carried out at the specified location. 7.2 Pressure relief valve When the differential pressure between the upstream and downstream of the check valve is less than 14 kPa, the pressure relief valve should be opened to ensure safety (passing the intermediate pressure zone to the atmosphere). The internal vertical distance h (in the non-connected position), the distance between the highest point of the pressure relief valve base and the lowest point of the upstream check valve base (See Figure 2) The following requirements should be met. ---DN≤15, h≥5mm; ---15 \u003cDN≤50时,h≥10mm。 Description. a Upstream. b Downstream. Figure 2 Pressure relief valve Water should not be allowed to remain in the intermediate pressure zone at all installation locations declared by the manufacturer. The cross section of the relief valve through hole should meet. when the DN >15, the cross section of the hole should be greater than or equal to 45mm2, or the cross of the hole when DN≤15 The section should be greater than or equal to 12.5 mm2; the dimensions not used to calculate the cross-sectional area should be less than 4 mm. The device with the funnel shall be drained at the full relief flow rate specified in Table 6. The pressure relief funnel should meet the following requirements. --- Directly incorporated into the device; ---Installed by the factory; --- Provided with the device. The structure of the pressure relief hole of the device shall be capable of being connected by gluing, welding or interlocking means, neither standard threaded pipe nor use Standard piping or fittings are connected. 7.3 Pressure tapping hole Three pressure taps shall be provided on the device for periodic verification of the effectiveness of the device function. The pressure tap holes shall be set at. ---Upstream of the first check valve; ---Intermediate pressure zone; --- Downstream of the second check valve. The size of the pressure tap should be as specified in Figure 3 and Table 2. The minimum cross-sectional area of the inner diameter of the pressure tap hole shall be 12.5 mm 2 . The minimum size of the pressure tap should be no less than 4mm. Table 2 Thread size of the pressure tap Nominal size DN Mm Thread mark G (according to ISO 7-1) Thread depth a Mm DN≤10 G1/8 or G1/4 ≥6.5 10 \u003cDN≤50 G1/4 ≥6.5 Description. G --- thread size; a --- thread depth. Figure 3 pressure tap hole size Each pressure tap should be equipped with a 1/4 cock, the size should meet the following requirements. --- DN ≤ 10 device, DN6 (G1/8 connection) internal threaded joint;8 Characteristics and tests8.1 General test conditions Install the unit as specified in the manufacturer's technical documentation and perform a performance test. If there are no special regulations, all tests should be carried out with clean water at an ambient temperature not exceeding 40 °C. If there are no special regulations, the measurement accuracy should meet the following requirements. ---Flow. ± 2% of the specified value; --- Pressure. ± 2% of the specified value; ---Water temperature. ±5 °C of the specified value; ---Time. 0~10% of the measured value. The accuracy of all other measuring instruments shall be ±2% of the measured value. 8.2 Test result report Record the measured value. The test results can be given in the form of a graph of pressure, flow or time. See Appendix A. 8.3 Test procedure All tests are carried out on the same device, except for the long-term withstand voltage test (8.7), and the long-term withstand voltage test can be used for another without internal components. On the device. The tests were carried out in the order of Table 3. Table 3 Test sequence Serial number test 1 valve body short-time pressure resistance 8.4.2 2 Closed check valve closing pressure and tightness 8.5.2 Table 3 (continued) Serial number test 3 Sealing of downstream check valves 8.5.1 4 Sealing of upstream check valve at low pressure 8.5.3 5 Relationship between pressure loss and flow rate 8.6.1 6 Pressure difference between upstream and intermediate pressure zones 8.6.2 7 Intermediate pressure zone and atmospheric conductivity when the upstream pressure drops 8.6.3 8 Pressure relief valve opening and closing pressure 8.6.4 9 Sealing of pressure relief valve when upstream pressure fluctuates 8.6.5 10 Pressure in the intermediate pressure zone under recirculation conditions 8.6.6 11 short-term durability test 8.4.3 12 Sealing of downstream check valves 8.5.1 13 closing pressure and sealing of downstream check valves 8.5.2 14 Sealing of upstream check valve at low pressure 8.5.3 15 Intermediate pressure zone and atmospheric conductivity when the upstream pressure drops 8.6.3 16 Sealing of upstream check valve under vacuum 8.5.4 8.4 Mechanical properties 8.4.1 General requirements Ensure that the test equipment can be tested as required. Note. The examples in the figure are for reference only. 8.4.2 Short-time pressure resistance of the valve body The hydrostatic pressure was continuously applied to 2.5 MPa at an inlet of the apparatus at an increment of 0.1 MPa per 5 s. Maintain this pressure for 5 min. Record the observations. The valve body or internal components of the device should not exhibit visible permanent deformation or rupture. 8.4.3 Short-term durability test 8.4.3.1 High temperature resistance The assembled device was placed in an environment at a temperature of 65 ° C and a relative humidity of (50 ± 5)% for 72 h. 8.4.3.2 Thermal shock After testing according to 8.4.3.1, immerse the device in water at 65 ° C for 60 min, so that all parts of the water should be touched when the device is working normally. The pieces are exposed to water. After 60 min, the device was immersed in a 15 ° C pool for 10 min. After the test is completed, the device is disassembled and inspected. Rubber and plastic parts should not have visible permanent deformation. 8.4.3.3 Cyclic pressure test After testing according to 8.4.3.1 and 8.4.3.2, the device was installed in the test device as shown in Figure 4, and was carried out in water at a temperature of 45 °C. (5000 ± 50) cycle tests, each cycle in the following order. ---Open the valve 5, and then open the valve 1; keep the flow within ± 5% of the value specified in Table 4, for (6 ± 2) s; ---Close the valve 5, then close the valve 1; ---Open the valve 3, maintain the pressure of 0.3MPa, lasting (6 ± 2) s; --- Close the valve 3, open the valve 4, and then let the device relieve pressure (open the pressure relief valve) for (6 ± 2) s; ---Close the valve 4; ---Open the valve 5, and then open the valve 1; keep the flow within ± 5% of the value specified in Table 4, for (6 ± 2) s; ---Close the valve 5, then close the valve 1; ---Open the valve 2, keep the pressure at 1MPa, lasting (6 ± 2) s; --- Close the valve 2, open the valve 4, and then open the pressure relief valve to allow the device to relieve pressure for (6 ± 2) s; ---Close valve 4. Description. A --- supply flow. the maximum pressure at zero flow is 0.3MPa; B --- supply pressure. 1MPa ± 0.05MPa; C --- supply pressure. 0.3MPa ± 0.03MPa; ---Regulating valve; --- Switching valve with time control; --- Safety device under test. Figure 4 cyclic pressure test device The 5000 cycles are divided into 4 phases according to the following requirements, each phase of 1250 cycles. a) 1250 cycles Allow the device to stand at room temperature for 14 h before proceeding to the next stage. b) 1250 cycles The device was held at 1 MPa static pressure and room temperature for 14 h before entering the next stage. c) 1250 cycles Before entering the final stage, a pressure of 0.3 MPa is applied upstream of the device and a pressure of 1 MPa is applied downstream, at room temperature. Lasts 14 hours. d) 1250 cycles At the end of the test, the unit shall meet the requirements of 8.5 and 8.6 without replacing any components. Table 4 Cycle Pressure Test---Flow Nominal size DN Mm 8 10 15 20 25 32 40 50 Flow rate m3/h 0.4 0.6 1.3 2.2 3.5 5.8 9 14 8.5 Seal test 8.5.1 Sealing of downstream check valves The test consists of the following steps. a) using the test device shown in Figure 4, using normal temperature water, pressurizing the downstream of the device at a pressure of 0.1 MPa every 5 s. Until the water pressure reaches 1.6MPa, and keep the upstream pressure zone and the atmosphere; b) holding pressure for 2 min; c) Separate the unit from the supply pressure source by closing valve 2 and valve 5 for 10 min. After the test, the downstream check valve should be free of leakage, permanent deformation or functional degradation. 8.5.2 Closing pressure and tightness of downstream check valves The test is to measure the height difference Δh of the water surface in the two vials shown in Figure 5. The test consists of the following steps. a) Determine the inner diameter of the vial is (10 ± 0.2) mm; b) adding water to the device so that the height h of the water column in the C pipe can satisfy two measurements; c) isolating the device for 5 min ± 30 s; d) record Δh1, see Figure 5a); e) slow drainage downstream; f) isolating the device for 5 min ± 30 s; g) Record Δh2, see Figure 5b). a) b) Figure 5 Closing the pressure test device The closing pressure of the check valve should be greater than 7 kPa and the height equal to 70 cm; Δh1 and Δh2 should be higher than 70 cm. Test results can draw music Line representation (example, see Figure A.1). 8.5.3 Sealing of upstream check valves at low pressure The test consists of the following steps. a) water is injected into the device so that the height of the water column in the horizontal tube shown in Figure 6 [inner diameter is (10 ± 0.2) mm] is (200 ± 50) mm; b) isolating the device for 5 min ± 30 s; c) raise the height of the water column in the leveling pipe to (1000 ± 50) mm; d) isolating the device for 5 min ± 30 s; e) raise the height of the water column in the leveling pipe to (2000 ± 50) mm; f) Isolation of the device lasts 5 min ± 30 s. The water level in the vial should be constant at each test step to verify the tightness of the upstream check valve at low pressure. At any test procedure, care should be taken that there is no reduction in the water level in the tube. Description. ---Isolation valve; ---Regulator valve. Figure 6 Sealing test device at low pressure 8.5.4 Sealing of upstream check valve under vacuum The test consists of the following steps. a) remove the downstream check valve; b) Mount the unit on the test bench (see Figure 7); c) adjusting the pressure relief flow so that the pressure in the intermediate zone reaches 14 kPa; d) Apply a vacuum pressure of 0.025 MPa quickly upstream of the unit and maintain a vacuum for 5 min. No water should be collected in the sump to verify the tightness of the upstream check valve under vacuum. Description. 1 --- vacuum instrument; 2 --- vacuum instrument; 3 --- vacuum pump; 4 ---vacuum container; 5 --- water collector; 6 --- water source; 9 --- the distance between the end of the valve and the vacuum gauge 2; ---Isolation valve; ---Regulator valve. Figure 7 Sealing test equipment under vacuum 8.6 Hydraulic characteristics 8.6.1 Relationship between pressure loss and flow 8.6.1.1 Test e......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of GB/T 36702.1-2018_English be delivered?Answer: Upon your order, we will start to translate GB/T 36702.1-2018_English as soon as possible, and keep you informed of the progress. The lead time is typically 1 ~ 3 working days. The lengthier the document the longer the lead time.Question 2: Can I share the purchased PDF of GB/T 36702.1-2018_English with my colleagues?Answer: Yes. The purchased PDF of GB/T 36702.1-2018_English will be deemed to be sold to your employer/organization who actually pays for it, including your colleagues and your employer's intranet.Question 3: Does the price include tax/VAT?Answer: Yes. 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