A 26 cc two-stroke petrol engine changes that arithmetic. The engine drives a high-pressure piston pump that holds working pressure between 15 and 25 bar no matter how long you have been walking, with a spray output of 3-8 litres per minute and a range of 15-25 metres. Pressure is what decides where a droplet lands: at 20 bar a fan or hollow-cone nozzle breaks the liquid into a fine, even mist that reaches the top of a mature canopy from the ground, so the operator sprays from the row instead of climbing a ladder with a hand lance.
The pump is where cheap units fail first. The 767 uses a brass (copper) pump body with a chromed stainless piston: copper fungicides, wettable powders and abrasive suspensions attack aluminium, and a scored piston loses pressure long before the engine wears out. The 20-25 litre PE tank has a wide filling filter, so you can pour from a bucket without leaves and grit going through the pump. Each carton holds the machine, a 1.2 m hose, two shoulder straps, a spray lance, an extension lance, a three-nozzle fan head, an adjustable spray gun and a parts kit with gaskets, tools and a spare nozzle - the items that are usually quoted separately.
It suits orchards, vineyards, greenhouses, rice and vegetable fields, livestock sheds and public sanitation work. Three habits keep it running: mix fuel at 25:1 with two-stroke oil, flush the pump with clean water after every corrosive chemical, and never let the pump run dry. Zhengzhou Weiwei Machinery has built farm machinery since 1980 in Xingyang, Henan, to CE and ISO9001 standards. Tell us your crop, row spacing and the spray volume you need per hectare, and we will confirm tank size and nozzle set, quote, and ship - or visit our homepage to see the full range and send an inquiry.A hand pump loses pressure every few metres, droplets grow and the spray runs off the leaf. A 26 cc knapsack power sprayer holds 15-25 bar all day, puts out 3-8 litres a minute and reaches 15-25 m, so one operator covers a row without a ladder. Here is what to check before you buy, and what should be in the carton.
