Experimental studies of deflagration flame quenching by crimped ribbon flame arrestors were performed in a circular ducting with propane-air flammable mixture. The corresponding flameproof velocities were determined systemically. The results showed that the channel length, the expansion ratio and the aperture size must be taken into consideration to predict the performance of the crimped ribbon flame arrestors. To explore the relationship between flameproof velocity and arrestor structure, numerical simulations were carried out. The simulated results showed that with the reduction of the hydraulic diameter of the aperture size, the flameproof velocity is increased, which implies the basic angle must be considered when crimped ribbon flame arrestors are used to quench deflagration flame. In addition, the influence of the expansion ratio is of great significance on the efficiency of flame arrestors. The flameproof velocity can be reduced to be a value related to the expansion ratio. Two empirical formulas were derived to exhibit the relation between the flameproof velocity and the characteristics of the flame arrestor, which can be used to predict the performance of crimped ribbon arrestors. (C) 2016 Elsevier Ltd. All rights reserved.