Coating Science Popularization: common problems and solutions of spray gun

In the process of using the spray gun, there are some problems sometimes Now, the phenomenon of the spray gun is analyzed in detail, and the causes are analyzed according to the phenomenon to find solutions Phenomenon: the center of gravity of the spray amplitude is inclined to one side Cause: the central hole or the atomizing hole of the air cap is blocked Countermeasures: 1 Clean the atomizing cap 2 Replace the atomizing cap Cause: 1 The fan control hole on one side of the air cap is blocked 2 The air cap is damaged Countermeasures: 1 Clean the atomizing cap 2 Replace the atomizing cap: the center of spraying amplitude is too thick The reasons are: 1 The viscosity of spraying coating is too high; 2 The spraying pressure is too low; 3 The diameter of nozzle and thimble are increased and reduced due to wear; countermeasures: 1 Reduce the viscosity of coating; 2 Increase the spraying pressure; 3 Replace the nozzle set Phenomenon: causes of spray amplitude splitting: 1 Too low viscosity of coating; 2 Too high spraying pressure; 3 Too large inner diameter of fan control hole; 4 Insufficient coating; 5 Blocking of atomizing air channel; countermeasures: 1 Increasing viscosity of coating; 2 Reducing spraying pressure; 3 Replacing nozzle set 4 Add enough paint 5 Clean the air channel of the spray gun Cause: 1 The nozzle is not tightened or installed 2 The sealing kit of the gun needle is loose 3 The connecting nut of the spray gun is loose (lower spray gun) 4 The paint in the pot is not enough 5 The nozzle package is damaged Countermeasures: 1 Tighten the nozzle or clean and install the nozzle set 2 Tighten the thimble seal set 3 Tighten the connecting nut 4 Supplement the coating 5 Replace the nozzle set Phenomenon: the spray amplitude is heavy or heavy Cause: 1 There are sundries blocking the air outlet of the nozzle, thimble or air cap 2 The air cap or nozzle is damaged Countermeasures: 1 Clean the nozzle set; 2 Replace the nozzle set; cause: 1 The air supplement hole of the gun pot cover is blocked or the air cap and suction pipe are seriously blocked; 2 There is no paint in the pot; 3 The travel of the thimble is too small Countermeasures: 1 Clean the air supplement hole, air cap and suction pipe on the pot cover; 2 Supplement paint; 3 Rotate the paint flow adjusting knob to increase the stroke of the needle valve; causes: 1 The sealing screw cap of the thimble is too tight; 2 There are foreign matters inside the nozzle port 3 The nozzle and thimble are not matched or damaged 4 The thimble return spring is broken or not installed Countermeasures: 1 Loosen the thimble seal nut 2 Clean the nozzle 3 Replace the nozzle set 4 Replace the thimble return spring or install the upper thimble return spring Phenomenon: the spray amplitude cannot be adjusted Causes: 1 The fan control holes on both sides of the air cap are blocked; 2 The spray amplitude regulator is damaged or installed incorrectly; 3 The air channel of the spray gun fan control hole is blocked; countermeasures: 1 Clean the air cap; 2 Replace the spray amplitude regulator or install the spray amplitude regulator correctly; 3 Clean the air channel Phenomenon: the air pressure cannot be regulated normally or the compressed air will be ejected directly from the muzzle when just connected Causes: 1 The air conditioner is damaged or the air valve is damaged 2 The return spring of the air valve is broken or not installed Countermeasures: 1 Replace the air conditioner or the air valve 2 Replace the return spring of the air valve or install the return spring of the air valve Leakage of paint on the thimble seal Causes: 1 The thimble seal ring is worn out; 2 The thimble seal ring gasket is not installed; 3 The thimble seal ring spring is damaged or not installed; 4 The thimble seal nut is loose; 5 The contact between the thimble and the seal ring is worn; 6 The thimble does not match the spray gun; countermeasures: 1 Replace the thimble seal ring; 2 Install the thimble seal ring gasket 3 Replace or install the thimble seal ring spring 4 Tighten the thimble seal nut 5 Replace the nozzle set 6 Replace the nozzle set matching the spray gun