JB/T7950- —1999 This standard is a revision of JB/T7950—95 "Quick Cutting Nozzle". This standard replaces JB/T7950-95 from the date of implementation. This standard is proposed and managed by the National Technical Committee for Welding Standardization. The drafting unit of this standard: Harbin Welding Research Institute. The main drafters of this standard: Lv Zhenjie, Wang Run, Liu Hongge. 603 ]Scope Machinery Industry Standard of the People's Republic of China Quick Cutting Nozzle Nozzle for high-speed flame cuttingJB/T 7950--1999 Replaces JB/T7950—95 This standard specifies the model marking method, technical requirements, inspection method and marking of various specifications and varieties of quick cutting nozzles. This standard applies to fast cutting nozzles for flame cutting machines and manual cutting torches, and can be used in conjunction with the cutting torches specified in JB/T7947 and JB/T6970. 2 Referenced standards The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and the parties using this standard should explore the possibility of using the latest version of the following references. GB/T2828-1987 Batch inspection counting sampling procedures and sampling tables (applicable to continuous batch inspection) JB/T6970-1993 Injection and suction cutting torch JB/T7947-1999 Isobaric welding torch, cutting torch 3 Specifications and models 3.1 Specifications The specifications of fast cutting nozzles are determined by the throat diameter of the cutting nozzle cutting the oxygen channel. The specifications and corresponding throat diameters are shown in Table 1. Table 1 Cutting nozzle specification and corresponding throat diameter Cutting nozzle specification Throat diameter d 3.2 Model 3.2.1 Fast cutting nozzles are manufactured by electroforming and machining, respectively represented by GK and GKJ6 3.2.2 The cutting oxygen pressure of fast cutting nozzles is divided into 0.7MPa and 0.5MPa. 0.7MPa is not marked, and 0.5MPa is marked by code A. 3.2.3 Fast cutting nozzles are divided into 4 varieties according to gas and tail cone angle, and their codes are as follows: 1 -30° tail cone acetylene cutting nozzle; 2--45° tail cone acetylene cutting nozzle -30° tail cone liquefied petroleum gas cutting nozzle 4-45° tail cone liquefied petroleum gas cutting nozzle. 3.2.4 Model designation Guohao Machinery Industry Bureau approved 604 on 1999-06-24 2000-01-01 buy bottle JB/T7950—1999 Cutting oxygen pressure code Specification code Variety code Manufacturing method code Example 1: GK2-5 indicates that the No. 5 acetylene fast cutting nozzle is manufactured by electroforming, the cutting oxygen pressure is equal to 0.7MPa, the tail cone angle is 45°, and the cutting oxygen channel diameter d is equal to 1.5mm. Example 2: GKJ3-4A indicates that the No. 4 liquefied petroleum gas fast cutting nozzle is manufactured by machining, the cutting oxygen pressure is equal to 0.5MPa, the tail cone angle is 30°, and the cutting oxygen channel throat diameter d is equal to 1.25mm. See Table 2 for various specifications of fast cutting nozzle models. Various specifications and varieties of fast cutting nozzle models Table 2: Processing method Electroforming Processing method Cutting oxygen pressure Electric gas Liquefied petroleum gas Liquefied petroleum gas Liquefied petroleum gas Tail cone GK1-1;GK1-2;GK1-3;GK1-4: GK1-5; GK1-6;GK1-7 GK2-1;GK2-2;GK2-3;GK2-4# GK2-5;GK2-6,GK2-7 GK3-1;GK3-2;GK3-3:GK3-4: GK3-5;GK3-6;GK3-7 GK4-1;GK4-2;GK4-3;GK4-4 GK4-5;GK4-6:G K4-7 | | tt | 1A;GK3-2A;GK3-3A:GK3-4A GK3-5A;GK3-6A; GK3-7A ||tt || t||GKJ2-1;GKJ2-2,GKJ2-3+GKJ2-41GKJ2-5+GKJ2-6 ;GKJ2-7 GKJ3-1+GKJ3-2+GKJ3-3+GKJ3-4,GKJ3-5GKJ3-6;GKJ3-7 GKJ4-1+GKJ4-2,GKJ4-3+GKJ4-4,GKJ4-5;GKJ4-6;GKJ4-7 GK J1-1A GKJ1-2A+GKJ1-3AGKJ1-4A,GKJ1-5A;GKJ1-6A:GKJ1-7A GKJ2-1A;GKJ2-2AGKJ2-3A+GKJ2-4A:GKJ2-5A GKJ2-6A,GKJ2-7A GKJ3-1A;GKJ3-2A;GKJ3-3A;GKJ3-4AGKJ3-5A;GKJ3-6A;GKJ3-7A GKJ4-1A,GKJ4-2A+GKJ4-3A:GKJ4-4AGKJ4-5A:GKJ4-6A;GKJ4-7A 4 Technical requirements JB/T 7950—1999 4.1 When the preheating flame is adjusted to the neutral flame, the flame shape should be symmetrical and the combustion should be stable. 4.2 Under the normal flame background, the cutting oxygen flow should be located in the center of the flame when visually observed, and should be straight, clear and powerful. Under the specified operating pressure, the visible cutting oxygen flow length should comply with the requirements of Table 3. Table 3 Visible cutting oxygen flow length Auxiliary nozzle specification number Visible cutting oxygen flow length ≥100 The cutting performance of the fast cutting nozzle shall comply with the provisions of Table 4. 3 ≥120 Table 4 Fast cutting nozzle cutting performance Specification number Throat diameter Cutting thickness 5~10 10~20 60~100 100~150 150~180 10~20 20~40 40~60 60~~100 Cutting speed mm/min 75 0~600 600~450 450~380 380-320 320~250 250~160bZxz.net 160~130 560~450 450-340 340-250 250210 210~180 Gas pressure The relevant interchangeable matching dimensions of No. 1 to 7 quick cutting nozzles shall comply with the requirements of Figures 1 and 2. 614 90(or 85) Figure 130° tail cone cutting nozzle matching dimensions ≥150 Liquid petroleum gas Incision width JB/T7950-1999 R5(or 80) Figure 245° tail cone cutting nozzle matching dimensions 4.5The coating thickness on the cutting oxygen channel profile of the GK type cutting nozzle shall not be less than 0.15mm. 5 Inspection method 5.1. Inspection of cutting oxygen flow According to the gas pressure specified in Table 4, adjust to a neutral flame after ignition. After stable combustion for 1 minute, open all the cutting oxygen regulating valves, observe and measure the visible cutting oxygen flow length, and inspect the cutting nozzles one by one according to the provisions of Table 3. 5.2 Inspection of cutting performance 5.2.1 Determination of cutting speed According to the provisions of Table 4, select a rolled steel plate of appropriate thickness with a length of 300mm and a carbon content not higher than 0.45%; the oxygen purity is not less than 99.5%, and use a linear cutting machine to perform vertical linear cutting on the surface of the steel plate. The measured cutting speed should comply with the provisions of Table 4. The sampling method for cutting inspection should comply with the provisions of GB/T2828. 5.2.2 Determination of incision width Use the workpiece thickness of 5.2.1 and the measured cutting speed (qualified product) to cut an incision of 80m in length, but do not cut it off. After the workpiece cools down, use a caliper or plug gauge to measure the incision width. The value should comply with the provisions of Table 4. The sampling method of cutting nozzles is the same as that of 5.2.1. 5.3 Inspection of cutting oxygen channel outlets 5.3.1 Determination of nickel plating The thickness of the nickel plating at the outlet is measured with a tool microscope. If the thickness measurement value is less than 0.15mm, it is a defective product. The sampling method is the same as that of 5.2.1. 5.3.2 Determination of outlet shape Cutting nozzles with non-cylindrical or chamfered deformation at the outlet are considered defective products. 6 Marking Each cutting nozzle should be marked with the model, manufacturer name or trademark. The position of each mark should be obvious and the handwriting should be clear. 607 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.