CB/T 702-1992 Technical requirements for cast iron cylinder liners for marine diesel engines

This standard specifies the technical requirements, test methods, inspection rules, transportation, marking, packaging and storage of cast iron cylinder liners for marine diesel engines. This standard applies to marine diesel engines with a cylinder diameter of not less than 200mm. CB/T 702-1992 Technical requirements for cast iron cylinder liners for marine diesel engines CB/T702-1992 Standard download decompression password: www.bzxz.net

People's Republic of China Ship Industry Standard
CB/T 702-92
Technical Specifications for Cast Iron Cylinder Liners for Marine Diesel Engines Issued on March 7, 1992
China State Shipbuilding Corporation
Implementation on October 1, 1992
People's Republic of China Ship Industry Standard
Technical Specifications for Cast Iron Cylinder Liners for Marine Diesel Engines 1 Subject Content and Scope of Application
CB/T 702-92
Classification Number: U44
Replaces CB702-68
This standard specifies the technical requirements, test methods, inspection rules and marking, packaging, transportation and storage of cast iron cylinder liners for marine diesel engines (hereinafter referred to as cylinder liners).
This standard applies to marine diesel engines with a cylinder diameter of not less than 200mm. 2 Technical requirements
2.1 The cylinder liner shall comply with the provisions of this standard and be manufactured according to the drawings and technical documents approved by the prescribed procedures. 2.2 The names of the various parts of the cylinder liner are shown in Figure 1.
2.3 The chemical composition, mechanical properties and metallographic structure of the cylinder liner material shall comply with the requirements of relevant standards and drawings. 2.4 Surface treatment of cylinder liner
2.4.1 The following surface treatments can be selected for cylinder liner: a.
Chrome plating on the inner surface (chrome plating on loose holes and chrome plating on oil storage points); nitriding;
Phosphating:
General mesh and platform grinding mesh;
Vibration cutting;
Squeezing and infiltration of silicon carbide;
Other surface strengthening treatments.
2.4.2 The thickness of the chrome plating layer on the inner surface is 0.03~0.05mm, and the thickness of the chrome plating layer on the oil storage point is 0.15%~0.2%D. The diameter of the oil-containing point is 1.0~1.5mm; the depth of the oil-containing point is 3/2, and the spacing of the oil-containing points is 3mm, and they are arranged crosswise. 2.4.3 The nitriding layer on the inner surface of the nitrided cylinder liner cannot peel off, the depth of the nitriding layer is 0.02~0.04mm, and the hardness is HV550~750.
2.4.4 Phosphating treatment of the inner surface requires that the phosphate film has a medium particle size and its thickness should be 0.03~0.04mm. 2.5 The cylinder liner should be subjected to aging annealing treatment to eliminate residual stress. 2.6 Cylinder liner manufacturing accuracy and shape and position tolerance 2.6.1 The inner diameter and tolerance of the cylinder liner should comply with the requirements of IT7 level. 2 When the inner diameter of the cylinder liner is at the bottom dead center of the piston, the inner surface below the ring is allowed to have a bell mouth, but it should comply with the requirements of 2.6.2
of the cylinder liner product drawing.
2.6.3 The cylindricity of the inner surface of the cylinder liner, the coaxiality of the inner surface to the upper and lower belts, and the runout of the lower end of the support shoulder to the center circle of the inner surface should reach level 8 accuracy.
Approved by China State Shipbuilding Corporation on March 7, 1992, implemented on October 1, 1992
CB/T702-92
Four-stroke cylinder liner
Two-stroke cylinder liner
1-upper end face, 2-inner surface; 3-inner angle of upper end face; 4-boss; 5-upper end face of supporting shoulder; 6-supporting shoulder; 7-lower end face of supporting shoulder; 8-recess; 9-upper belt; 10-outer chamfer of lower end face; 11-inner chamfer of lower end face; 12-lower end face; 13-cut; 14-lower edge; 15—lower belt; 16—water sealing groove; 17—water jacket wall; 18—air inlet or exhaust port
2.7 Cylinder liner surface roughness
Inner surface of cylinder liner:
Surface roughness R of chrome plating is 0.20μm;
Surface roughness R of nitriding is 0.40μm;
Surface roughness R of phosphating is 0.80μm; Surface roughness R of general mesh and platform honing mesh is 0.8μm; Surface roughness R of vibration cutting is 0.80μm; Surface roughness R of extruded silicon carbide is 0.80um. For other cylinder liners after surface strengthening treatment, the roughness shall be in accordance with the product drawings or technical documents. 2.7.2 Cylinder liner outer surface
Surface roughness R of the upper and lower end faces of the bearing shoulder, the upper and lower belts of the cylinder liner and the outer circumference of the water sealing groove. 0.80um The surface roughness R of the upper and lower end faces is 1.6μm. 2
CB/T 702---92
2.7.3 The surface roughness R of the machined surface of the gas port (exhaust port, scavenging port) is 12.5um. 2.8 Appearance quality of cylinder sleeve
2.8.1 Cylinder sleeves are not allowed to have casting defects such as cracks, slag inclusions and looseness. The fine-machined surface is not allowed to have defects such as bruises and corrosion. 2.8.2 Under the condition that it does not affect the performance, separate holes are allowed to exist on the inner and outer surfaces of the cylinder sleeve, but their position, size and number shall comply with the requirements of the drawings and technical documents.
3 Test method
Hydraulic test of cylinder sleeve density: a hydraulic test of 0.7MPa is carried out over the entire length for 5 minutes, and there should be no leakage or infiltration. 4 Inspection rules
The cylinder liner leaving the factory should have the inspection certificate of the inspection department of the manufacturer and the ship inspection certificate. Inspection items:
Appearance quality;
Mechanical properties;
Metallurgical structure;
Hardness;
Surface roughness;
Geometric dimensions,
Shape and position tolerances;
Hydraulic test;
Other items specified in product drawings and technical documents. 4.3 Sampling for mechanical property tests and metallographic microstructures shall be in accordance with the drawings and technical documents. 4.4 Hardness test shall be carried out at 3 points evenly distributed on the upper end face of the cylinder liner, near the inner surface hole, and the average value shall be taken. The hardness difference of the same cylinder liner shall not be greater than HB30.
4.5 Visual inspection shall be adopted for the inspection of appearance quality. 4.6 The inner diameter of the cylinder liner shall be measured at the upper, middle and lower cross sections. The upper and lower measuring sections should be at the two extreme positions of the first ring stroke of the piston. bzxz.net
5 Marking, packaging, transportation and storage
After the cylinder liner is inspected and qualified, the manufacturer's name or trademark, ship inspection stamp, factory date and furnace number shall be stamped in appropriate positions. 5.1
The cylinder liner must be cleaned and oil-sealed before packaging, and wrapped with strong moisture-proof materials, and the certificate and inspection record shall be placed. 5.31
When packaging, it should be fixed with a strong wooden box and moisture-proof measures should be taken. 5.4 The packaging box should be marked with:
Manufacturer name and address;
Product name and model:
Gross weight and quantity;
Receiving unit and address;
"Handle with care", "Moisture-proof", "Pressure-proof" and other signs; factory date.
Additional Notes:
CB/T 702—92
This standard was proposed by the 603 Institute of China State Shipbuilding Corporation. This standard is under the jurisdiction of the National Marine Machinery Standards Technical Committee, Marine Diesel Sub-Technical Committee. This standard was drafted by the 711 Institute. The main drafter of this standard is Bai Taoyang.
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