JB/T 7295-1994 Technical requirements for chrome-plated steel cylinder liners for internal combustion engines
Some standard content:
Mechanical Industry Standard of the People's Republic of China
JB/T7295-94
Steel chrome-plated cylinder liners for internal combustion engines
Technical conditions
Published on July 18, 1994
Ministry of Machinery Industry of the People's Republic of China
Implementation on July 1, 1995
Mechanical Industry Standard of the People's Republic of China
Steel chrome-plated cylinder liners for internal combustion engines
Technical conditions
1 Subject content and scope of application
JB/T 729594
This standard specifies the terminology, technical requirements, inspection rules, inspection methods, marking, packaging, transportation and storage of chrome-plated cylinder liners for internal combustion engines.
This standard applies to steel chrome-plated cylinder liners for reciprocating internal combustion engines with a cylinder diameter less than or equal to 130mm (hereinafter referred to as cylinder liners). 2 Reference standards
GB1031
GB1184
GB1800
GB1958
GB2828
GB4340
GB4955
GB4956
GB5270
GB6388
GB6462
GB9790
ZBJ92011
3 Terminology
Packaging, storage and transportation pictorial symbols
Metal tensile test methods
Surface roughness parameters and values of hot-rolled thin steel plates and strips of high-quality carbon structural steel
Shape and position tolerances Provisions for tolerances not indicated Tolerances and fits General introduction to standard tolerances and basic deviations Differential shape and position tolerance inspection regulations
Batch inspection counting sampling procedures and sampling tables (applicable to continuous batch inspection) Metal Vickers hardness test method
Metal coating thickness determination Anodic dissolution Coulomb method Non-magnetic coating thickness measurement on magnetic metal substrate Magnetic method Adhesion strength test method of metal coating (electrodeposition layer and chemical deposition layer) on metal substrate Transport packaging delivery and receipt mark
Metal and oxide coating cross-sectional thickness Microscope measurement method Metal coating and other related coating Vickers and Knoop microhardness test Internal combustion engine cylinder liner platform grinding reticulation technical conditions and test methods: 3.1 Steel chrome-plated cylinder liner
The main body is low-carbon carbon steel, the inner surface is chrome-plated with metal coating, and the outer four surfaces are not directly in contact with the engine cooling water. 3.2 The main parts of the typical structure of the cylinder are shown in Figure 1. Approved by the Ministry of Machinery Industry on July 18, 1994
Implemented on July 1, 1995
4 Technical requirements
JB/T7295-94
1-Support upper end face; 2-Support shoulder outer circle, 3-Support shoulder lower end face, 4-External surface: 5-Inner drawing surface chrome plating layer: 6-Guide part: 7-Lower end face, 8-Lower surface inner round chamfer 4.1 Cylinder liner shall be manufactured according to product drawings and technical documents approved by the prescribed procedures. 4.2 Mechanical propertieswwW.bzxz.Net
4.2.1 The tensile strength of the cylinder liner body shall be greater than or equal to 345MPa, 4.2.2 Hardness
4.2.2.1 The hardness of the cylinder liner body is 130~250HVag. 4.2.2.2 The inner circle surface is hard chrome plated, and the hardness of the chrome covering layer shall be greater than or equal to 800HV1%. 4.3 The thickness of the chromium coating is 0.04~0.10mm. 4.4 The adhesion strength of the chromium coating and the base metal. After the test in 5.3.4, there shall be no peeling or residual phenomenon on the inner surface of the cylinder liner.
4.5 Dimensional accuracy
4.5.1 The tolerances of the inner diameter and outer diameter of the cylinder liner shall comply with the IT7 grade specified in GB1800. 4.5.2 When the cylinder liner is grouped according to the inner (outer) diameter size, it shall be grouped within the diameter size tolerance range specified in the product drawing, and the product shall be classified into groups according to the minimum (maximum) size. The size grouping interval shall be less than or equal to 0.02mm. The maximum (minimum) size of the inner (outer) diameter of the cylinder liner can exceed the upper (lower) limit size of the group. In extreme cases, the excess value shall be less than or equal to twice the cylindrical tolerance specified in Article 4.6.
The grouping code is represented by A, B, C..***. (a, b, c), and the order is from the smallest (largest) size group to the largest (smallest) size group. 4.5.3 The difference in wall thickness between the inner and outer circles of the cylinder liner: The wall thickness difference of the cylinder liner with a cylinder diameter less than 100mm is 0.04mm: The wall thickness difference of the cylinder liner with a cylinder diameter greater than or equal to 100mm is 0.06mm. 4.5.4 The thickness tolerance of the support shoulder is 0.05mm, or as specified in the product drawing. 4.5.5 The inner ring hole of the upper end face is outside the stroke range of the piston ring, and a bell mouth caused by the machined surface is allowed. The increment of the bell mouth should be less than 0.03mm.
4.6 Shape and position tolerance
4.6.1 The cylindrical tolerance of the inner surface of the cylinder sleeve shall meet the 8th grade specified in GB1184 after being pressed into the standard cylinder hole, or the roundness tolerance of the inner surface of the cylinder sleeve measured in the free state is 0.06mm. The parallelism tolerance of the inner surface line to the center line is 0.015mm.
JB/T7295-94
4.6.2 The cylindrical tolerance of the outer surface of the cylinder sleeve shall be less than or equal to the 8th grade specified in GB1184 after being pressed into the standard cylinder hole, or the parallelism tolerance of the outer surface line to the center line is 0.06mm when measured in the free state. The parallelism tolerance of the outer surface line to the center line is 0.015mm. 4.6.3 The end face runout tolerance of the lower end face of the support shoulder to the axis of the outer surface is 0.03mm. 4.7 Surface roughness
4.7.1 The outer surface roughness R is 1.25μm. 4.7.2 The surface roughness R of the upper and lower end faces of the bearing shoulder is 3.2μm. 4.7.3 The average value of the surface roughness R of the inner chrome cover layer is 0.50~1.20μm, and the allowable range is 0.40~1.30um. 4.8 The surface structure of the inner chrome cover layer 4.8.1 The surface structure of the chrome layer can be a platform grinding mesh or a dotted platform mesh structure. 4.8.2 The angle of the grinding mesh in the direction of the center line of the cylinder liner is 130°~150°4.8.3
The surface wheel deflection S is equal to -0.8~-3.0. 4.8.4 Within the piston ring stroke range, the contour support length ratio, value should meet the requirements of Figure 2. o
p value example
4.8.5 Within the piston ring travel range, the groove depth of the mesh is within the sampling length of 4mm, and there are at least 5 grooves greater than or equal to 4um.
4.8.6 The mesh in both directions should be uniform and clear, without sharp corners, burrs, metal folds and inclusions. 4.9 Appearance quality
4.9.1 The chromium covering layer on the inner surface of the cylinder liner is not allowed to have defects such as delamination, peeling, burning, rust and chromium tumors. 4.9.2 The surfaces of the cylinder liner are not allowed to have cracks, rust and silicon bumps that affect the performance. 4.10: Warranty period
The warranty period of the cylinder liner shall not be less than the warranty period of the main engine. During the warranty period, if the user is damaged due to manufacturing quality under normal use conditions, the manufacturer shall replace it for the user free of charge. 5 Inspection rules and inspection methods
5.1 Cylinder liner products must be inspected and qualified by the quality inspection department of the manufacturer according to the product drawings and relevant technical documents before they can leave the factory. 5.2 Inspection items
a. Mechanical properties:
b. Hardness of chromium coating:
Thickness of chromium coating;
Dimensional tolerance:
Shape and position tolerance;
Surface roughness:
Appearance quality;
JB/T 729594
h. Special requirements specified in product drawings and technical documents. 5.3 Inspection method
5.3.1 Inspection of mechanical properties of cylinder liner body. Random inspection shall be conducted on raw materials before entering the factory and storage, or on semi-finished products before plating. 5.3.1.1 Tensile test. Before entering the factory and storage, the plate shall be inspected according to the method specified in GB710; the seamless steel pipe shall be inspected according to the provisions of GB228; the semi-finished cylinder liner before chrome plating shall be cut on the cylinder liner body for testing. The tensile test shall be conducted according to the provisions of GB228. And its tensile strength shall be calculated.
5.3.1.2 Hardness inspection shall be conducted according to the provisions of GB4340. 5.3.2 Hardness inspection of chromium layer shall be conducted according to the provisions of GB9790. 5.3.3 Inspection of chromium layer thickness shall be conducted according to the microscope measurement method of GB6462, the coulomb method of GB4955, and the magnetic method of GB4956. One of them can be selected according to the working conditions and the workpiece conditions. 5.3.4. The bonding strength test between the chromium coating and the body is tested by the bending test method or grinding test method specified in GB5270. The bending test method is to clamp the test piece on a bending test machine or bench vise with a bending radius of 10mm, as shown in Figure 3. After bending 90° forward and backward, the test piece is restored to its original state, and the bending part is observed with a 45x magnifying glass to check whether the coating has any residual phenomenon. The grinding test method is to fix the test piece on the grinder, grind slowly while adding grinding oil, and the feed depth is less than 5um each time. The grinding wheel cutting direction is from the base metal to the coating, and check whether the inlay has peeling or blistering. Wu
5.3.5 Dimensional inspection
5.3.5.1 Measurement of the inner diameter: After the cylinder sleeve is assembled, measure any two mutually perpendicular diameters of the three inner sections of the upper, middle and lower sections. The upper and lower bearing surfaces are the two extreme positions of the piston ring stroke, but if the lower extreme position is less than 30mm from the lower increase surface, it should be measured at 30mm. When the cylinder liner is measured in a free state, the maximum and minimum values at the three measuring positions should be measured. The average value of each cross-sectional diameter should be calculated respectively.
5.3.5.2 Measurement of the outer diameter: After the cylinder liner is recirculated, measure the diameters of any two of the upper, middle and lower cross-sections in the outer drawing that are multiplied by each other. The upper and lower load surfaces are 30mm away from the upper and lower end surfaces respectively (or as specified in the product drawing). When the cylinder liner is measured in a free state, the maximum and minimum values at the three measuring positions should be measured. The average value of each cross-sectional diameter should be calculated respectively. 5.3.5.3 The wall thickness difference between the inner and outer circular surfaces: Measure the radial wall thickness on the circular solid at the upper and lower extreme positions of the piston ring stroke and take the maximum difference.
5.3.5.4 Bearing shoulder thickness measurement. Measure four points evenly on the circle. Take the maximum value. 5.3.6 Shape and position tolerance
JB/T7295-94
5.3.6.1 Cylindricity of the inner surface, the measurement position is the same as 5.3.5.1, according to the method specified in 1-1 of Appendix 1 (4) Cylindricity error detection of GB1958. When the detection equipment and conditions cannot meet the requirements, cylindricity can be replaced by measuring roundness and parallelism of the cable line to the center line. Roundness can be measured by measuring the maximum and minimum values of the inner diameter of the radial section, and the calculation is calculated by taking half of the difference. The parallelism of the element line to the center line allows the measurement of the maximum and minimum values of the inner diameter size of the same axial section of the inner circle surface. Take half of the difference for calculation. 5.3.6.2 The inverted cylinder of the outer surface, the measurement location is the same as 5.3.5.2, according to the method specified in 1-1 of Appendix 1 (4) of GB1958 Cylindrical error detection. When the detection equipment and conditions cannot meet the requirements, the cylinder is allowed to be replaced by measuring the roundness and the parallelism of the cable line to the center line. The maximum and minimum values of the inner diameter size of the radial section are allowed to be measured, and half of the difference is taken for calculation. The parallelism of the element line to the center line allows the measurement of the maximum and minimum values of the inner diameter size of the same axial section of the outer surface, and half of the difference is taken for calculation. 5.3.6.3 The measurement of the end face circular runout of the lower end face of the support shoulder to the axis of the outer ring surface is in accordance with the method specified in 4-7 of Appendix 1 (13) of GB1958 Runout detection.
5.3.7 Surface roughness
5.3.7.1 The surface roughness shall be measured according to GB1031. Five points of the inner surface shall be measured within the piston ring travel range and the average value shall be taken.
5.3.7.2 The surface quality of the chrome coating on the inner surface and the morphological structure of the oil storage wheel shall be evaluated according to the method specified in ZBJ92011. 5.3.7.3 The uniformity and cleanliness of the grinding mesh and the point platform shall be directly observed with a microscope or checked by the laminating method. The evaluation shall be carried out according to the three groups of graphs in Figure 4.
5.3.8 The appearance quality inspection shall be carried out by visual inspection. 5.3.9 The inspection of special requirements specified in the product drawings and technical documents shall be agreed upon by the supply and demand parties. 5.3.10 Reference figure of surface contour curve
During the production process, the use of sampling method to control the quality of surface wheel seat curve is one of the important means to control product quality. Figure 5 is a group of wheel contour curves for reference during evaluation.
5.4 When the ordering unit samples the product quality, it shall be carried out in accordance with the provisions of GB2828. The sampling method and evaluation method shall be agreed upon by the supply and demand parties. 6 Marking, packaging, transportation and storage
6.1 Each cylinder sleeve shall be marked with:
a. Manufacturer name or trademark;
b. Group code.
The marking shall be permanent, and the marking position, size and method shall be in accordance with the provisions of the product drawing or technical documents, and the cylinder sleeve shall not be damaged. 6.2 When the cylinder sleeve leaves the factory, it shall be accompanied by a product certificate signed by the inspector of the quality inspection department of the manufacturer. 6.3 The packaging method and means of cylinder liners shall be determined by the manufacturer in accordance with the regulations of the transportation department or through consultation with the ordering unit, and shall ensure that the product will not be damaged under normal transportation conditions.
6.4 The markings on the outer surface of the packaging box shall comply with GB6388 and GB191 and other relevant regulations. Generally, the following shall be indicated:
Manufacturer name and address;
Product name, model,
Factory date (year, month);
Volume (length × width × height), mm;
Weight, kg:
Quantity:
“Be careful to scatter”, “moisture-proof” and “pressure-proof” and other signs. g
6.5 The packaging boxes of cylinder liners shall be placed in a ventilated and dry warehouse. The anti-rust method of cylinder liners shall be determined by the manufacturer. Under normal storage conditions, they will not rust within 12 months from the date of shipment. Or it shall be determined by negotiation between the supply and demand parties. 5
JB/T7295--94
Figure 4a High-quality oil tanker structure
JB/T7295-94
Figure 4b Qualified oil tanker gallery structure
JB/T729S94
Figure 4c Unqualified oil tanker seat structure 100×2 The surface quality of the chrome coating on the inner surface and the morphological structure of the oil storage wheel profile shall be evaluated according to the method specified in ZBJ92011. 5.3.7.3 The uniformity and cleanliness of the grinding mesh and the point platform shall be directly observed with a microscope or checked by the lamination method. Evaluate according to the three groups of graphs in Figure 4.
5.3.8 Visual inspection shall be used for appearance quality inspection. 5.3.9 Inspection of special requirements specified in product drawings and technical documents shall be agreed upon by the supply and demand parties. 5.3.10 Reference diagram of surface profile curve
In the production process, the use of random inspection method to control the quality of the surface wheel seat curve is one of the important means to control product quality. Figure 5 is a group of wheel profile curves for reference during evaluation.
5.4 When the ordering unit samples the product quality, it shall be carried out in accordance with the provisions of GB2828. The sampling method and evaluation method shall be agreed upon by the supply and demand parties. 6 Marking, packaging, transportation and storage
6.1 Each cylinder sleeve shall be marked with,
a. the name or trademark of the manufacturer;
b. the grouping code.
The marking shall be permanent, and the marking position, size and method shall be in accordance with the provisions of the product drawings or technical documents, and the cylinder sleeve shall not be damaged. 6.2 When the cylinder sleeve leaves the factory, it shall be accompanied by a product certificate signed by the inspector of the quality inspection department of the manufacturer. 6.3 The packaging method and method of the cylinder sleeve shall be determined by the manufacturer in accordance with the provisions of the transportation department or in consultation with the ordering unit, and shall ensure that the product will not be damaged under normal transportation conditions.
6.4 The marking on the outer surface of the packaging box shall comply with GB6388 and GB191 and other relevant regulations. Generally, the following should be indicated:
Manufacturer name and address;
Product name, model,
Factory date (year, month);
Volume (length × width × height), mm;
Weight, kg:
Quantity:
“Caution”, “Moisture-proof” and “Pressure-proof” signs. g
6.5 The packaging boxes of cylinder liners should be placed in a ventilated and dry warehouse. The anti-rust method of cylinder liners is determined by the manufacturer. Under normal storage conditions, they will not rust within 12 months from the date of shipment. Or it can be agreed upon by the supply and demand parties. 5
JB/T7295--94
Figure 4a High-quality oil tanker structure
JB/T7295-94
Figure 4b Qualified oil tanker gallery structure
JB/T729S94
Figure 4c Unqualified oil tanker seat structure 100×2 The surface quality of the chrome coating on the inner surface and the morphological structure of the oil storage wheel profile shall be evaluated according to the method specified in ZBJ92011. 5.3.7.3 The uniformity and cleanliness of the grinding mesh and the point platform shall be directly observed with a microscope or checked by the lamination method. Evaluate according to the three groups of graphs in Figure 4.
5.3.8 Visual inspection shall be used for appearance quality inspection. 5.3.9 Inspection of special requirements specified in product drawings and technical documents shall be agreed upon by the supply and demand parties. 5.3.10 Reference diagram of surface profile curve
In the production process, the use of random inspection method to control the quality of the surface wheel seat curve is one of the important means to control product quality. Figure 5 is a group of wheel profile curves for reference during evaluation.
5.4 When the ordering unit samples the product quality, it shall be carried out in accordance with the provisions of GB2828. The sampling method and evaluation method shall be agreed upon by the supply and demand parties. 6 Marking, packaging, transportation and storage
6.1 Each cylinder sleeve shall be marked with,
a. the name or trademark of the manufacturer;
b. the grouping code.
The marking shall be permanent, and the marking position, size and method shall be in accordance with the provisions of the product drawings or technical documents, and the cylinder sleeve shall not be damaged. 6.2 When the cylinder sleeve leaves the factory, it shall be accompanied by a product certificate signed by the inspector of the quality inspection department of the manufacturer. 6.3 The packaging method and method of the cylinder sleeve shall be determined by the manufacturer in accordance with the provisions of the transportation department or in consultation with the ordering unit, and shall ensure that the product will not be damaged under normal transportation conditions.
6.4 The marking on the outer surface of the packaging box shall comply with GB6388 and GB191 and other relevant regulations. Generally, the following should be indicated:
Manufacturer name and address;
Product name, model,
Factory date (year, month);
Volume (length × width × height), mm;
Weight, kg:
Quantity:
“Caution”, “Moisture-proof” and “Pressure-proof” signs. g
6.5 The packaging boxes of cylinder liners should be placed in a ventilated and dry warehouse. The anti-rust method of cylinder liners is determined by the manufacturer. Under normal storage conditions, they will not rust within 12 months from the date of shipment. Or it can be agreed upon by the supply and demand parties. 5
JB/T7295--94
Figure 4a High-quality oil tanker structure
JB/T7295-94
Figure 4b Qualified oil tanker gallery structure
JB/T729S94
Figure 4c Unqualified oil tanker seat structure 100×
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.