Wear performance of bionic strip-shaped mud pump pistons

The service life of mud pump pistons may be extended by imitating the body surface morphology of earthworms. To achieve this solution, bionic strip structures of various sizes are processed on the working surface of a BW-160 mud pump piston. The service lives of standard and bionic pistons are compared under experimental conditions. Results show that the bionic strip structure clearly improves the service life of mud pump pistons. The influence of the width of a bionic piston strip is greater than that of strip spacing. The bionic strip should not be too small or large because size could have negligible or deleterious effects on service life, respectively. The optimal structure parameters of a bionic strip piston when the optimal contact area between the piston and the cylinder liner is 73.5% are a strip width of 3 mm, strip spacing of 3 mm, and strip number of 3. These parameters improve piston service life by 81.5%. Finite element analysis simulations of wear demonstrate that the bionic strip can change the stress state on the working surface of the piston, increase lubricant storage space, improve the wear resistance of the piston, reduce extrusion injuries on the root, and prolong piston service life.