GB 11701-1989 Basic provisions for marine gangways

This standard specifies the technical requirements and test methods for gangways. This standard applies to single-section or multi-section gangways on merchant ships (except passenger ships). GB 11701-1989 Basic provisions for marine gangways GB11701-1989 standard download decompression password: www.bzxz.net

UDC 629.12.046
National Standard of the People's Republic of China
GB 1170189
Basic rules for marine ladders
The general rules for marine accommodation ladders
Issued on October 14, 1989
Implemented on May 1, 1990
State Administration of Technical Supervision
National Standard of the People's Republic of China
Basic rules for marine ladders
The general rates for marine accommodation laddersThis standard is equivalent to the international standard ISO5488-79 "Shipbuilding ladders". 1 Subject content and scope of application
This standard specifies the technical requirements and test methods for ladders. This standard applies to single-section ladders or multi-section ladders for merchant ships (except passenger ships). 2 Types
GB 11701-89
2:1 Rotating platform ladder
The structure of a single-section ladder or a multi-section ladder is hinged to the upper rotating platform, and can change the direction and inclination angle between the ship and the bottom of the ladder. The ladder can be hung from the lower suspension point by wire ropes or chains, or supported by rollers fixed to the bottom of the ladder (see Figures 1 and 2). 2.2 Fixed semi-platform ladder
The structure of the ladder is hinged to the upper fixed platform, and can change the inclination angle between the ship and the bottom of the ladder. The ladder is hung from the lower suspension point(s) by wire ropes or chains (see Figures 1 and 2). This ladder can also be a single-section or multi-section ladder structure. 8 Terms and codes
3.1 Nominal length L
The nominal length of a single-section ladder is the distance from the center of the top pin to the center of the support pin of the platform under the string ladder (see Figure 1). 3.1.1
Intermediate hanging
Nominal length: L
Design length: L
Figure 1 Single-section ladder
Approved by the State Administration of Technical Supervision 198g-10~14 and implemented on 1990-05-01
GB 11701-B8
8.1.2 The nominal length of a multi-section ladder is the sum of the distances from the center of the top pin of each section to the center of the lower half pin of the ladder (see Figure 2).
Middle hanging section
Nominal length: f, = Ls + I.,
Design length: Each section ladder L
Figure 2 Multi-section ladder
3.2 Design length L
The maximum distance between the supporting ends of each section ladder (see Figures 1 and 2) 3.3 Design width 6
The effective width of the step (see Figure 3). 3.4 Handrail height convex
Refers to the vertical height of the handrail. When the ladder is laid flat, it is the distance from the step plane to the highest point of the handrail (see Figure 3). The sections shown in the figure are each an example.
Figure 3 Minimum width 6 and handrail height
Structural dimensions
4.1 Arrangement of nominal length L,
Increase by 0,6m within 3.6~7.2 m:
Increase by 1.2m within 7.2~21.6m,
Increase by 1.8m within 21.6~30.6m.
Design width
The width of all staircases is 600 mm.
4.3 Step spacing
GB 11T01—89
Step spacing refers to the distance between the protruding parts of the step along the diagonal line, which is 300 mm. 4.4 Handrail height a
The handrail height should not be less than 1000 mm, and the middle handrail should be set at half the handrail height (see Figure 3). Construction
5.1 Design
5.1.1 Minimum angle of use
Both types of ladders can be fully used in the horizontal position. 5.1.2 Maximum angle of use
While keeping the steps horizontal, the ladder can be safely used from horizontal to 55°. 5.1.3 Design load
When the ladder is in the half position, (supported by the center of the two end pins), each step bears a load of 735N. 5.1.4 Design of steps
Each step is designed to withstand a load of 735N at the midpoint. 5.1.5 Design load of ladders and intermediate platforms
The platform should be designed to withstand a load of 4000N/m. The upper and intermediate platform frames and their suspension structures should also bear the weight of the ladder they support, plus the load specified in 5.1.3. 5.1.6 Design load of handrails
Each handrail and support should be designed to withstand a lateral load of 500N/m without permanent deformation. 5.1.7 Support points
All support points (axles, columns, etc.) and suspension points (earrings, brackets, etc.) should be able to support the weight of the ladder plus the load specified in 5.1.3.
5.1.8 Safety factor
When designing a ladder, the allowable stress should take into account the external load specified in 5.1.3, and the safety factor should be 2. For steel materials, it refers to the service point, and for aluminum materials, it refers to the proof stress (Prow of stress) of 0.2%. The ladder frame and steps of the ladder should be made of steel or aluminum alloy as specified in the table below. It can also be made of the same material approved by the user. NamebZxz.net
Ladder, ladder frame, etc.
Magnetic structural steel
Rust-proof calcium
Q235-A
L.F2, LF 5LF11
Standard number
GB 700—88
GR 3190--
GB 3194—82
6 Test
6.1 Procedure
GB11701-89
When each step ladder is placed in a horizontal position, the instrument is only supported at the center of the two end pins of the design length L (see Figure 4). A load equivalent to 735N should be added to each step of the ladder. In order to verify the longitudinal strength and measure the maximum deformation size. For multi-section ladders, each section ladder can be tested in the same way.
Maximum deformation
Total length between two cross braces L
Figure 4 Test method for each ladder
6.2 Measurement and inspection
6.2.1 When the load is applied, the maximum deformation of each ladder section should not exceed the specified value. The steel ladder is L2/100; the aluminum ladder is Lz/75. 6.2.2 After the test, the ladder should be carefully inspected to ensure that there is no sign of damage and no permanent deformation. Additional remarks:
This standard was proposed by China State Shipbuilding Corporation. This standard was officially established by Shanghai Shipbuilding.
This standard was drafted by Dalian Shipbuilding. The main drafter of this standard was Jia Changzhen.
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