During the use of pneumatic hoists, the steel cylinder may deform, and the design accuracy and surface roughness of the steel cylinder affect the friction resistance and gas leakage of the pneumatic hoist. 

Therefore, it is necessary to conduct a detailed design of the wall thickness, length, processing accuracy, and surface roughness of the steel cylinder from the overall design of the gas hoist.

In addition, considering the small wall thickness of the steel cylinder and the high requirements for accuracy and surface roughness of the steel cylinder, it is easy to deform and difficult to machine parts. 

Therefore, the processing technology of the steel cylinder has been explored and optimized to improve the processing accuracy of the thin-walled steel cylinder. 

From the perspective of driven seals, lower frictional resistance and smaller gas leakage are contradictory. 

In order to reduce the friction between the steel cylinder and the piston, on the one hand, it is necessary to minimize the contact positive pressure between the steel cylinder and the piston as much as possible, and on the other hand, the sealing components in contact with the steel cylinder need to use materials with smaller friction coefficients. 

The paper solves the relationship between the surface roughness of the steel cylinder, sealing contact pressure, and gas leakage through finite element simulation, and deduces the optimal piston groove size using Matlab. 

Based on orthogonal experiments, a PTFE wear-resistant ring combined with an O-ring Glay ring sealing structure is used for sealing, which not only reduces the friction coefficient between the steel cylinder and the sealing component but also improves its sealing performance, At the same time, it also improves the positioning accuracy of the pneumatic hoist.

As a safer lifting device, the brake of the pneumatic hoist needs to be able to work quickly, safely, and reliably, with the cam and spring being key components of the brake. 

On the basis of a detailed analysis of the force acting on the brake, the eccentricity of the cam and the brake spring were designed and optimized, and the braking process of the brake was simulated using the finite element simulation software ABAQUS. 

The stiffness or spring force of the spring was calculated using the internal force of the straight rod. 

Then, the designed and calculated spring stiffness was compared with the finite element simulation results, and the simulation results were consistent with the calculation results.

Through experimental research on key performance indicators of the pneumatic hoist, such as load capacity, stroke, gas leakage, friction resistance, braking performance, and steel cylinder stress-strain, 

the goals of small deformation of the steel cylinder, low friction and high sealing between the steel cylinder and the piston, and reliable braking of the brake were achieved, verifying the rationality of the overall design of the pneumatic hoist.