Industry Projects
Mechanical Projects Road Transport
Internship Program-Project Program-Product Dev, Program
UNIT I
Four Exmples from Text Book will be given trainingOn software listed For the program Four problem will be given for self training with software to Trainee
The company STC "APM" performed a strength calculation of the frame and body of the NEFAZ 9509-30 dump semitrailer in order to subsequently increase its carrying capacity and reduce metal intensity.
The body of the semi-trailer is a metal welded structure with a folding tailgate with a top hitch. In transport condition, the entire length of the body rests on the spars of the load-bearing welded frame. The dump truck is unloaded backwards, through the folding side. Tipping is carried out using a telescopic hydraulic cylinder. The tipping angle is 45 degrees. The chassis is a three-axle air suspension. The suspension was not modeled.
Geometric dimensions of the curb semi-trailer: length 9961 mm, width 2250 mm, height 3450 mm. Curb semi-trailer weight: 9800 kg. Weight of the simulated part of the semi-trailer (only body and frame): 6420 kg.
The calculation was carried out by order of OJSC Neftekamsk Automobile Plant in the APM WinMachine software product.
UNIT IV
Four Exmples from Text Book will be given trainingOn software listed For the program Four problem will be given for self training with software to Trainee
Analysis of the results of the static calculation shows that at the specified loads, the equivalent stresses arising in the structural elements of the semi-trailer when using the specified sections do not exceed the design resistance of the materials used (with the exception of local zones associated with the presence of stress concentrators in the model), i.e. the required strength is provided.
The available margin of safety made it possible to optimize the design of the semi-trailer, thereby reducing the weight. The metal intensity decreased by 781 kg, which is 12% of the original model of the semi-trailer. At the same time, reinforcing elements were also introduced into the model, locally increasing the strength characteristics of the structure.
The work carried out showed the applicability of the APM WinMachine software package for solving complex problems of strength analysis of road transport.
UNIT II
Four Exmples from Text Book will be given trainingOn software listed For the program Four problem will be given for self training with software to Trainee
To make calculations, the customer provided the following data:
model of the frame and body of the semi-trailer-dump truck;information on the loads acting on the semi-trailer;materials used.
UNIT III
Four Exmples from Text Book will be given trainingOn software listed For the program Four problem will be given for self training with software to Trainee
Modeling and Calculation
The elements of the semi-trailer were modeled using plate finite elements.
The semi-trailer rests on the ground through a three-axle suspension. The suspension was modeled by rigid ties connecting the axles of the wheels and the places where the suspension was attached to the frame.
The connection of the semi-trailer with the tractor is carried out through the fifth wheel of the tractor.
Effective loads:
- Dead weight of the structure;
- Cargo weight;
Loads from movement with acceleration:
- Acceleration acceleration;
- Acceleration of braking;
- Acceleration of turning;- Driving on rough roads;
- Torsion of the frame with the body;
- Mode of lifting the body with a load.
To assess the strength of the structure, the calculation was made for various combinations of load cases.
Static analysis was carried out in the module for calculating the stress-strain state, stability, natural and forced oscillations of parts and structures using the finite element method - APM Structure3D, which is part of the APM WinMachine computer-aided analysis and design system for industrial and civil construction.
As a result of the calculations, maps of the stressed and deformed state of the frame and body structure at the appropriate combinations of loads were obtained.
According to the results of the calculations, the structure of the frame and body was optimized. Recommendations are given for strengthening the weakest elements of the semi-trailer and reducing the thickness of underloaded elements.
