ZONGSHEN ZS250GY-3(EFI), Руководство по обслуживанию

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LISH
[3] Rivet joint and welding
Rivet joint is a process which can join two parts or more together with rivets.It is widely used in
maintenance,such as rivet joint of clutch disc and so on. Classified by its function,rivet joint can be
divided into fixed rivet joint,active rivet joint and seal rivet joint.
Welding is a process which can bring into close union of two metal parts with welding tool and solder.
It is also widely used in maintenance,such as repairing the crack of frame and other metal parts.
[4] Drilling and Reaming
Drilling is a process which drills holes on parts or materials with drill bit.The drilling tools mainly
include beam drill
、
bench drill
、
electric hand drill
、
rotary hand drill
、
drill bit and clamp.
[2] Rubbing
Rubbing is to rub out a thin layer from the surface of parts by grinder and crocus.This is a fine finish
for the surface of parts,which can provide a precise size ,exact geometrical shape and the lowest degree of
roughness.It includes flat rubbing,internal rubbing and external rubbing.The rubbing tool for flat rubbing
is a plane plate,while internal rubbing tool is a pestle.During maintenance,rubbing methods are usually
used for rubbing the flat of crankcase and internal hole of connecting rod.
[2] Carbon Deposit Removing
To remove the carbon deposit on component,we can use mechanical method or chemical method.
Mechanical method is that scrape deposit with bamboo-scraper or spade and clean them with gasoline.
Immerse the component,brush the carbon deposit off and clean them with hot water,which is called
chemical method.
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Parts Inspection
Inspect the parts after cleaning.The purpose for inspection is to check whether the parts need to be repaired or
replaced.There are three methods,i.e.direct inspection,instrument inspection and troubleshooting.
[1] Direct Inspection
Direct inspection is to check and judge the condition of parts by individual sensation instead of instrument.It is a
simple and feasible method,which is widely used for maintenance.
[2] Instrument Inspection
Instrument inspection is to measure the size and geometry shape of parts by gauge and apparatus;then compare
the measured value with limiting value to figure out the condition of parts.This method can get an accurate
judgement,but it needs careful inspection for the precision of instrument and reasonable selection of parts.
[3] Troubleshooting
To find the latent fault of parts
，
we can apply troubleshooting.Usually we adopt the method of oil
immersion and knock during maintenance.The process of this method is as following.First,immerse the
parts into coal oil or diesel oil for several minutes.Second,take out and wipe the parts.Third,spread talcum
powder on the surface of parts. Finally, knock the non-working surface of parts gently with a small hammer
. In this way,the knock can produce vibration and oil that has remained in crack will splash for vibration.
The splashed oil will dye the talcum powder yellow,so we can easily find a yellow mark in crack place.
Cleaning methods for non-metal parts differ in different materials.The best detergent for rubber parts is alcohol.Do not
use coal oil or gasoline to clean rubber parts,because they can cause inflation and deformity of rubber parts.Gasoline is
suitable for clutch disc and brake pads friction disc,while aqueous alkali is forbidden.
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Repair methods and skills
After disassembly,cleaning and inspection,the following is the principal stage.Mastering the basic skill
well is the key to ensure a good quality of maintenance.The skills for maintenance are as following:
[1] Chiseling,filing and scraping
Chiseling is to process metal parts by hammer and chisel. The functions are cutting and parting.
Filing is to rasp off the surface of parts by a file.It includes rasp and delicate filing.Teeth of a file directly
decide the roughness degree when filing metal parts.The operation of file is different because of different
shape surface of parts.
Scraping is a process which scrapes off a thin layer from the surface of parts. It is a delicate work, so we
should scrape the parts bit by bit with great care.Usually,scraping off 0.005
～
0.01mm each time.Before
scraping,we need to spread red lead on the surface of parts.Then,match the parts with standard one.The
unmatched parts are the aim of scraping.After several match and scraping,the contact surface of parts is
bigger.So it reaches the requirement and achieves the purpose.