I. Engine cylinder sealing performance testing

There are seven factors that affect the sealing performance of cylinders, mainly including cylinder wear, piston ring damage, piston wear, valve seat damage, valve guide wear, cylinder gasket damage, and valve clearance issues.

What are the commonly used diagnostic methods? Mainly, they include measuring cylinder pressure, crankcase air flow, cylinder leakage and leakage rate, vacuum degree of intake pipe, vibration measurement of abnormal noise caused by excessive wear of the cylinder piston group, and determination of the content of worn metal particles in the crankcase.

For the measurement of cylinder compression pressure, it mainly refers to the pressure at the end of compression in a four-stroke engine. Due to factors such as the pressure of the cylinder, the viscosity of the engine oil, and the coordination of the cylinder and piston groups, as well as the correctness of the valve train adjustment and the sealing performance of the cylinder gasket, when measuring the pressure of the engine cylinder, the sealing condition of the cylinder and piston groups can be diagnosed. If the sealing performance of the piston rings, valves, and cylinder gaskets is good, then the valve clearance must be appropriate.

Ii. Muffler Firmness Test

The muffler is composed of an outer cylinder and an internal honeycomb component. Due to being in a special environment such as high temperature and vibration, the two parts are combined together by mechanical interlocking technology. It is well known that the quality of this process depends on the precision of the design. If it is not firmly combined, it may become loose or fall off during car use due to factors such as high temperature and vibration. However, it can be assured that the relevant quality first department has already put forward quite strict requirements for this technical aspect.

In the actual testing method industry, universal material testing machines are used as testing tools. Pressure-resistant plate fixtures are employed to subject the two components of the muffler to relevant shear forces up and down. The repeatability error of the measured results should be less than 5%.

Iii. Interior Inspection

The interior includes seat bonding materials, interior box decoration materials and adhesives for bonding. The main tests for its safety are: 1. Gas harmfulness 2. Flame retardancy.