English English
Plastic extruder Gearbox

Plastic extruder Gearbox

Plastic extruder Gearbox, extruder gearbox manufacturers, extruder gearbox for sale, extruder gearbox repair,sterling extruder gearbox, twin screw extruder gearbox

ZLYJ series hard surface gearbox is a high-precision hard-toothed belt thrust seat transmission component designed for plastic screw extruder. The product design adopts the technical specifications specified in JB/T8853-2001. It features high-strength alloy steel for gear and shaft parts. The gear is processed by carburizing, quenching and grinding. Gear accuracy is GB10095-88.6. Tooth surface hardness HRC54-62. An over-sized thrust bearing is arranged at the front end of the hollow output shaft to withstand the working axial force of the screw. The main standard parts such as bearings and oil seals are made of domestic high-quality products, and can also be equipped with imported products according to user needs. The whole machine has the characteristics of small volume, high carrying capacity, stable transmission, low noise and high efficiency. Product performance has reached the international advanced level.

 Plastic extruder Gearbox 

Performance characteristics:

The combination of the box and the thrust bearing counteracts the axial force, and the inferential bearing is arranged at the oil chamber of the gearbox to improve the operational reliability.

Small adjustments can be used to adjust the center distance

High transmission power, can withstand high torque and axial force

The special Gearbox for extruder is a transmission component with high load capacity hard tooth surface with thrust seat designed with reference to foreign similar products for plastic screw extruder. The product design adopts the technical specifications stipulated by ZBJ19009-88. Its characteristics are that the gears and shaft parts are made of high-strength alloy steel, processed by carburizing, quenching and grinding. Gear accuracy is GB10095-88, level 6. Tooth surface hardness HRC54~62. A large-sized thrust bearing is arranged at the front end of the hollow input shaft to withstand the axial thrust of the screw. The whole machine has the advantages of small volume, high carrying capacity, stable transmission, low noise and high efficiency.

Extruder special Gearbox features:

——Modular design, wide transmission range and fine and reasonable distribution;

——The shape design is suitable for all-round universal installation configuration;

——The gear is ground by high-precision gear grinding machine with balanced transmission, low noise and 98% efficiency between stages;

 Plastic extruder Gearbox

Plastic extruder Gearbox

Extrusion machine dedicated Gearbox applicable conditions:

1. The speed of the high speed shaft of the Gearbox is not more than 1500r/min.

2, the working environment temperature is 0-35C. When the temperature range is beyond the provisions, the heating or cooling device can be separately prepared according to user requirements.

Plastic extruder GearboxGearbox for Plastic extruder

  1. Introduction

ZLYJ Plastic extruder Gearbox are a kind of high-precision rigid gear assembly specially designed for the single-screw plastic/rubber extruder. Taking the JB/T 8853-2001 Cylindrical Plastic extruder Gearbox as a reference for design, the products applies the high-strength low-carbon alloy steel for gears and gear shaft, with tooth flank carbureted, quenched and ground, to meet the gear precision at Level 6 (GB/T 10095) and hardness of tooth flank HRC54~62. A huge thrust bearing is mounted on the front of the output shaft to bear the thrust from the screw.

  1. Use Scope
  • The input rotation of prime mover shall be ≤ 1500 rpm.
  • The peripheral speed of gear drive shall be ≤ 20m/s.
  • The working ambient temperature shall be within -40℃~45℃. Preheat the lubricating oil to above 0℃ or choose the low temperature lubricating oil when the ambient temperature is below 0℃.

Note:

  • Rotation is available both forwards and backwards. However, the high-speed shaft of some types of Plastic extruder Gearbox has a single-way oil pump directing as defaulted to the output shaft which rotates clockwise.

III. Plastic extruder Gearbox Types

Product nameplates: When delivered, all Plastic extruder Gearbox are attached with nameplates to specify the type, capability, production date, ex-factory number and other features for the purpose of maintenance, which shall not be removed at random.

  1. Installation and Connection of Plastic extruder Gearbox
  • Make sure the installing foundation of Plastic extruder Gearbox is level, secure and stable. Carefully lay out the installation in special working environment. When all anchor bolts are evenly tightened, ensure that the screw inserted into the output shaft turns freely and regularly.
  • Error compensation connection shall prevail in respect of the connection of Plastic extruder Gearbox to prime mover. Ensure the concentricity of the connecting part of the axial midline of Plastic extruder Gearbox’s input shaft. Check the axial deviance and angular displacement, the deviation of which two shall be within the allowed value of the coupling applied.
  • Check the additional radial durability of the shaft of Plastic extruder Gearbox according to the product sample on condition that the belt wheel, gear and chain wheel are used to input and output the driving force of Plastic extruder Gearbox. At the middle part of the input shaft, the additional radial force shall be no more than(N), in which the input moment of Plastic extruder Gearbox (N.M).
  • After installation, fill into the Plastic extruder Gearbox the lubricating oil until reaching the center line of oil pointer when evenly distributing.
  • Connect to and turn on the water cooling system to check whether the joints bleed or leak.
  • Turn on the power to temporarily run the Plastic extruder Gearbox without load. Check whether the lubricating pipeline bleeds or leaks, the parts and components loosen and any noise occurs. The Plastic extruder Gearbox may be handed over if everything is OK.

Plastic extruder Gearbox

Attention:

Cut off and prevent (by a warning tag, etc.) the re-connection of power supply to the motor before installing the couplings.

      ◇  Striking by hammer or other similar tools is not allowed when mounting the couplings and small gears onto the shaft end.

      ◇  Ensure the correct tension of belt when installing belt wheel.

              ◇ Do not install or uninstall the screw by force in respect of the output part.

Protective hood shall be provided to the outside rotating parts of the Plastic extruder Gearbox (such as the coupling, belt pulley, etc.).

Remove thoroughly the antirust, dirt or other stains on the end and flange surface of connecting shaft. Solvent is permitted for cleaning but it shall be prevented from flowing to the lip seal of sealing elements of shaft end.

  1. Operation of Plastic extruder Gearbox

Examinations before operation:

  • Before operation, check whether the Plastic extruder Gearbox has lubricating oil to the appropriate level inside it. Supplement the oil in case of shortage.
  • All connecting parts shall be secure. All protective devices shall be complete.
  • Check whether the ambient environment is below 0℃, if yes, preheat the lubricating oil to above 0℃.

Plastic extruder Gearbox

Operation of Plastic extruder Gearbox:

  • Run the Plastic extruder Gearbox for 5~10 minutes without load (if the Plastic extruder Gearbox is equipped with the gear pump of motor, start the pump first) to appropriately lubricate the bearings and gears. If the Plastic extruder Gearbox is used for the first time, after the idle running, add loads step by step at 20% of rated load each time for 1~2 hours until the full rated load. Put into service if everything is OK.
  • During the operation, monitor and write down from time to time the temperature rise of the Plastic extruder Gearbox. If the temperature rise of the Plastic extruder Gearbox exceeds 70℃ or the oil temperature exceeds 100℃, stop the Plastic extruder Gearbox to find out and solve the problems. Contact our after-sales service department if necessary. Replace the lubricating oil before starting the Plastic extruder Gearbox again.
  • The Plastic extruder Gearbox shall be stopped as follows: Shut down the feeding hopper and, after all the materials in the bucket has been transported out, turn off the power supply to the Plastic extruder Gearbox (if the Plastic extruder Gearbox is equipped with the gear pump of motor, shut down the pump first)
  • Run the Plastic extruder Gearbox every 2 to 3 weeks in the event of long idleness.
  • Conduct anti-rust measures to the inside and outside of Plastic extruder Gearbox in the event of idleness over 6 months:

Fill in lubricating oil up to full, coat the shaft end and unpainted surface with anti-rust wax materials and protect with lubricating grease the lip seal of sealing parts of axles against the penetration of antirust.

Attention:

◇ During the early stage of operation, the oil pump may incur loud noise resulted from the high viscosity of lubricating oil and the large suction resistance against the oil pump, which would gradually die away along with the temperature rise of the lubricating oil

◇ If the oil pump incurs loud noise during the normal operation of Plastic extruder Gearbox, clean the oil filter to get the oil pipeline through.

Monitor from time to time the oil leak of the Plastic extruder Gearbox during its operation, and, if any, stop the Plastic extruder Gearbox to solve the problem.

  1. Repair and Maintenance
  • Time interval of repair and maintenance

Time interval

Repair and maintenance

Normal operation

Check the temperature of Plastic extruder Gearbox:

no more than 90℃ when using mineral lubricating oil

          no more than 100℃ when using synthetic lubricating oil

Check whether there is abnormal noise of Plastic extruder Gearbox

Check whether there is leakage of  Plastic extruder Gearbox

After 500~800 hours operation

First lubricating oil replacement after initial operation

Check the oil level to determine the oil filling

Every 3000-hour operation, at least once half a year

Check the lubricating oil, and, in case of outdoor or damp environment, ensure that the water content in lubricating oil shall be no more than 500ppm

Replace the mineral lubricating oil (working hour less than 8h per day)

Clean the air plug

As per operating condition, at least once 3 month

Replace the mineral lubricating oil (long time continuous work)

Check whether there is any joint bolt loosing

Check the situations of contamination and lubricating and cooling devices

Clean the filter of lubricating oil and replace filter core if required

As per operating condition, at least once a year

Replace the synthetic lubricating oil

As per the environment and operating condition

Improve or replace the protective (rustproof) paint on surface

Clean the exterior surface and of Plastic extruder Gearbox

Check the accessory devices equipped

  • Time interval of lubricating oil replacement

Plastic extruder Gearbox

Regularly replace the lubricating oil of special type Plastic extruder Gearbox that works in severe environment.  The figure below shows the time interval of lubricating oil replacement in normal environment. CLP HC refers to PAO synthetic lubricating oil.

(1) Operation time (2) Continuous temperature in oil bath (average value of 70℃)

VII. Fault Analysis and Solutions

Faults

Causes

Solutions

 

Faults

Causes

Solutions

Abnormal and regular operational noise

A. Rolling /milling noise: bearing  damaged

B. Knocking noise:  uneven joggling

A. Check the lubricating oil and replace the bearing

B. Contact Guomao

Leakage of lubricating oil: Junction surface of Plastic extruder Gearbox

End cover surface of Plastic extruder Gearbox

Cover of sight hole of Plastic extruder Gearbox

Sealing point of drive shaft

Oil discharge plug

Air plug

Loosening of connecting parts of Plastic extruder Gearbox

Loosening of connecting fastener

Incorrect installation of sealing parts

Damage/abrasion of sealing parts

Loose connection

Too much oil level of lubricating oil

Incorrect installation

Check the connecting bolts and tighten the loose ones if required

Check the sealing part and replace it if required

Check oil level/ improve exhaustion

Contact Guoma

Abnormal and    non-regular  operational noise

Impurity of lubricating oil

Check the lubricating oil, stop operation and contact Guomao

Abnormal noise in  fixed parts of Plastic extruder Gearbox

Fastener of Plastic extruder Gearbox looses

Check the fasteners and use the those specified

Too high temperature of  operation

A. To much lubricating oil

B. Aging and  deterioration of lubricating oil

C. Plentiful impurity in lubricating oil

D. Damage of lubricating pump

E. Fault of  cooling system

A. Check oil level and make modification if required

B. Check the replacement time of lubricating oil

C. Check the lubricating oil

D. Check the  lubricating pump and replace it 

E. Check the  cooling system

Too high  temperature on the bearing

A. Insufficient lubricating oil

B. Aging and  deterioration of lubricating oil

C. Damage of lubricating pump

D. Damage of bearing

A. Check oil level and make modification if required

B. Check the replacement time of lubricating oil

C. Check the  lubricating pump and replace it

D  Check the bearing and replace it

Over-high temperature on sealing point of shaft end in running-in period

Insufficient cleaning of connection of shaft end during installation

Running-in of sealing parts and shaft end

Clean the shaft end

Consider it as normal

Contact  Guoma


When contacting Guomao, please provide the following information:

Complete data on nameplate

-

Types and scopes of faults

-

Time and phenomena of faults occurred

   -

Causes

Plastic extruder Gearbox

Plastic extruder Gearbox

VIII. Selection of Lubricating Oil

The viscosity of lubricating oil shall be determined in accordance with the peripheral velocity V, working environment or lubricating method of the high-speed gears:

When V≤2.5m/s or ambient temperature is within 35℃~50℃, choose the CKC320 medium-load industrial closed gear oil or CKD320 heavy-load industrial closed gear oil;

When V>2.5m/s or forced circulating lubrication is applied, choose the CKC220 medium-load industrial closed gear oil or CKD220 heavy-load industrial closed gear oil.

Lubricant

 Lubricating grease is not recommended for Plastic extruder Gearbox. Contact us if required.

See Annex-Lubricating Oil Comparison Table for domestic and foreign lubricating oil products

  1. Wear Parts

List of Wear Parts of Plastic extruder Gearbox 

Packing List of Plastic extruder Gearbox

Annex - Lubricating Oil Comparison Table (Mineral Lubricating Oil):

Category

ISO VG

AGMA

Supplier

Type of Lubricating Oil

Viscosity /40℃

Freezing Point ℃

 

Category

ISO VG

AGMA

Supplier

Type of Lubricating Oil

Viscosity /40℃

Freezing Point ℃

220

220

5EP

Aral

Degol BG220

220

-21

320

320

6EP

Aral

Degol BG320

320

-18

BP

Energol GR-XP220

210

-27

BP

Energol GR-XP320

305

-24

Castrol

Alpha SP220

220

-21

Castrol

Alpha SP320

320

-21

Castrol

Alphamax 220

220

-24

Castrol

Alphamax 320

320

-18

Chevron

Industrial Oil EP220

220

-12

Chevron

Industrial Oil EP320

320

-9

Dea

Falcon CLP220

220

-18

Dea

Falcon CLP320

320

-18

Esso

Spartan EP220

226

-30

Esso

Spartan EP320

332

-27

Exxon

Spartan EP220

226

-30

Exxon

Spartan EP320

332

-27

Fuchs

Renolin CLP220 Plus

223

-23

Fuchs

Renolin CLP320 Plus

323

-21

Gulf

Gulf EP Lubricant HD220

219

-19

Gulf

Gulf EP Lubricant HD320

300

-12

Klüber

Klüberoil GEM 1-220

220

-15

Klüber

Klüberoil GEM 1-320

320

-15

Kuwait

Q8 Goya 220

220

-21

Kuwait

Q8 Goya 320

320

-18

Mobil

Mobilgear 630

207

-18

Mobil

Mobilgear 632

304

-18

Mobil

Mobilgear XMP 220

220

-24

Mobil

Mobilgear XMP 320

320

-18

Molub-Alloy

MA-90/220

220

-18

Molub-Alloy

MA-90/320

320

-15

Optimol

Optigear BM220

233

-15

Optimol

Optigear BM320

338

-15

Petro Canada

Ultima EP220

223

-30

Petro Canada

Ultima EP320

320

-21

Shell

Omala Oil F220

220

-21

Shell

Omala Oil F320

320

-18

Texaco

Meropa 220

209

-21

Texaco

Meropa 320

304

-18

Total

Carter EP220

220

-12

Total

Carter EP320

320

-12

Tribol

Tribol 1100/220

222

-25

Tribol

Tribol 1100/320

317

-23

GB5903-95

Domestic

CKC220

198~242

≤-8

GB5903-95

Domestic

CKC320

288~352

≤-8

GB5903-95

Domestic

CKD220

198~242

≤-8

GB5903-95

Domestic

CKD320

288~352

≤-8

 Plastic extruder Gearbox

Annex - Lubricating Oil Comparison Table (PAO Synthetic Lubricating Oil):

Category

ISO VG

AGMA

Supplier

Type of Lubricating Oil

Viscosity cSt

Freezing Point ℃

 

Category

ISO VG

AGMA

Supplier

Type of Lubricating Oil

Viscosity cSt

Freezing Point ℃

40℃

100℃

40℃

100℃

220

220

5EP

Dea

Intor HCLP220

220

25.1

-36

320

320

6EP

Dea

Intor HCLP320

320

33.9

-33

Esso

Spartan Synthetic EP220

232

26.5

-39

Esso

Spartan Synthetic EP320

328

34.3

-36

Exxon

Spartan Synthetic EP220

232

26.5

-39

Exxon

Spartan Synthetic EP320

328

34.3

-36

Fuchs

Renolin Unisyn CLP220

221

25.8

-42

Fuchs

Renolin Unisyn CLP320

315

33.3

-39

Klüber

Klübesynth EG 4-220

220

26

-40

Klüber

Klübesynth EG 4-320

320

38

-40

Mobil

Mobilgear SHC XMP 220

220

28.3

-45

Mobil

Mobilgear SHC XMP 320

320

37.4

-39

Mobil

Mobilgear SHC 220

213

26

-51

Mobil

Mobilgear SHC 320

295

34

-48

Optimol

Optigear Synthic A220

210

23.5

-36

Optimol

Optigear Synthic A320

290

30

-36

Shell

Omala Oil HD220

220

25.5

-48

Shell

Omala Oil HD320

320

33.1

-42

Texaco

Pinnacle EP220

220

25.8

-48

Texaco

Pinnacle EP320

320

35.2

-39

Total

Carter EP/HT220

220

25

-39

Total

Carter EP/HT320

320

33

-36

Tribol

Tribol 1510/220

220

24.6

-42

Tribol

Tribol 1510/320

330

33.2

-39

Tribol

Tribol 1710/220

220

-

-33

Tribol

Tribol 1710/320

320

-

-30

Domestic

Great Wall

4405/220

221.3

-

-42

 

 

 

 

 

 

Domestic

Great Wall

4406/220

225.3

-

-42

Domestic

Great Wall

4406/320

330.5

-

-40

Plastic extruder Gearbox
Single screw extruder principle
The single screw is generally divided into three sections in the effective length. The effective length of the three sections is determined according to the diameter of the screw and the pitch of the screw. Generally, it is divided into one third.
The last thread of the material port is called the conveying section: the material is required to be plasticized here, but it must be preheated and compacted. In the past, the old extrusion theory believed that the material here was loose, and later proved that the material here is actually The solid plug, that is to say, the material here is a solid like a plug after being squeezed, so it is its function as long as the conveying task is completed.
The second section is called the compression section. At this time, the volume of the groove is gradually reduced from large to large, and the temperature is to reach the degree of plasticization of the material. Here, the compression is generated by the conveying section three, where it is compressed to one, which is called the compression ratio of the screw -- 3:1, some machines have also changed, and the finished plasticized material enters the third stage.
The third section is the metering section, where the material maintains the plasticizing temperature, just as accurately and quantitatively transports the melt material as the metering pump to supply the head, at which time the temperature cannot be lower than the plasticizing temperature, generally slightly higher.
Extruder energy saving editor
The energy saving of the extruder can be divided into two parts: one is the power part and the other is the heating part.
Power saving: Most of the inverters are used. The energy saving method is to save the residual energy of the motor. For example, the actual power of the motor is 50Hz, and you only need 30Hz in production to produce enough. The excess energy consumption is vain. Wasted, the inverter is to change the power output of the motor to achieve energy saving.
Energy saving in heating part: Most of the energy saving in heating is energy saving by electromagnetic heater, and the energy saving rate is about 30%~70% of the old resistor ring.
work process
The plastic material enters the extruder from the hopper, and is transported forward by the rotation of the screw. During the forward movement, the material is heated by the barrel, sheared by the screw and compressed to melt the material. Thus, a change between the three states of the glassy state, the high elastic state, and the viscous flow state is achieved.
In the case of pressurization, the material in a viscous flow state is passed through a die having a certain shape, and then becomes a continuum having a cross-section and a mouth-like appearance according to the die. It is then cooled and shaped to form a glassy state, thereby obtaining the part to be processed.
Composition editor
In the extruder, in general, the most basic and most versatile is a single screw extruder. It mainly includes: six parts: transmission, feeding device, barrel, screw, machine head and die.

Plastic extruder Gearbox
Transmission section
The transmission part is usually composed of an electric motor, a reduction gear box and bearings. During the extrusion process, the screw speed must be stable and cannot change with the change of the screw load, so as to maintain the uniform quality of the obtained product. However, in different occasions, the screw can be required to be shifted to achieve the requirement that one device can extrude different plastics or different products. Therefore, this part generally uses AC commutator motor, DC motor and other devices to achieve stepless speed change, the general screw speed is 10~100 rev / min.
The function of the transmission system is to drive the screw, which supplies the torque and speed required by the screw during the extrusion process, usually consisting of a motor, a Gearbox and a bearing. Under the premise that the structure is basically the same, the manufacturing cost of the Gearbox is roughly proportional to its external dimensions and weight. Because the shape and weight of the Gearbox are large, it means that there are many materials consumed during manufacturing, and the bearings used are also relatively large, which increases the manufacturing cost.

Feeding device
Most of the feedstocks are pelletized, but strips or powders can also be used. The charging equipment usually uses a conical hopper with a volume requirement of at least one hour. A shut-off device is provided at the bottom of the hopper to adjust and cut the flow, and a sight hole and a metering device are installed on the side of the hopper. Some hoppers may also have a pressure relief device or heating device that prevents the feedstock from absorbing moisture from the air, or some of the cartridges may also have their own agitator for automatic feeding or feeding.


Hopper
The hopper is generally made in a symmetrical form. A window is opened on the side of the hopper to observe the material level and the feeding condition. The bottom of the hopper has a opening and closing door to stop and adjust the feeding amount. Cover the top of the hopper to prevent dust, moisture and impurities from falling into it. When selecting the material of the hopper, it is best to use lightweight, corrosion-resistant and easy-to-machine materials, generally using aluminum and stainless steel plates. The volume of the hopper depends on the size of the extruder and the loading method. Generally, the extrusion amount of the extruder is from 1 to 1.5 hours.


Plastic extruder Gearbox
There are two types of feeding methods: manual feeding and automatic feeding. The automatic feeding mainly includes spring feeding, blast feeding, vacuum feeding, conveying belt conveying and the like. In general, small extruders are manually loaded and large extruders are automatically loaded.


Classification of feeding methods
1 Gravity feeding:
Principle - The material enters the barrel by its own weight, including manual feeding, spring feeding, and blasting.
Features - simple structure and low cost. However, it is easy to cause uneven feeding, which affects the quality of the parts. It is only suitable for small size extruders.
2 Forced feeding:
Principle - Install a device in the hopper that applies external pressure to the material, forcing the material into the barrel of the extruder.
Features - can overcome the "bridge" phenomenon, so that the feeding is even. The feed screw is driven by the extruder screw through the drive chain to adjust its speed to the screw speed. The overload protection device can be activated when the feed port is blocked, thereby avoiding damage to the feeding device.
Cartridge
Generally, it is a metal material barrel made of alloy steel or composite steel pipe lined with alloy steel. Its basic characteristics are high temperature and pressure resistance, strong wear and corrosion resistance. Generally, the length of the barrel is 15 to 30 times its diameter, and the length is such that the material is sufficiently heated and plasticized uniformly. The barrel should have sufficient thickness and rigidity. The interior should be smooth, but some of the barrels are engraved with various grooves to increase the friction with the plastic. Electric heaters, temperature control devices and cooling systems are provided on the outside of the barrel with resistors, inductors and other means of heating.

Gearbox for Plastic extruder

There are three forms of material in the barrel:
(1) integral barrel
Processing method - processed on the whole material.
Advantages - easy to ensure high manufacturing accuracy and assembly accuracy, can simplify the assembly work, the cylinder is heated evenly, and more applications.
Disadvantages - Due to the large barrel length and high processing requirements, the requirements for processing equipment are also very strict. The inner surface of the barrel is difficult to repair after wear.
(2) Combination material
Processing method - the barrel is processed in several stages, and then the sections are connected by flanges or other forms.
Advantages - simple processing, easy to change the aspect ratio, mostly used to change the aspect ratio of the screw.
Disadvantages - high processing precision requirements, due to many segments, it is difficult to ensure the coaxiality of each segment, the flange connection breaks the uniformity of barrel heating, increases heat loss, heating and cooling system settings and maintenance More difficult
(3) Bimetallic barrel
Processing method - Inlay or cast a layer of alloy steel material inside the base of ordinary carbon steel or cast steel. It not only meets the material requirements of the barrel, but also saves precious metal materials.

Plastic extruder Gearbox
1 Bushing cartridge: The cartridge is fitted with a replaceable alloy steel bushing. Saving precious metals, the bushings can be replaced, and the life of the barrel is increased. But its design, manufacturing and assembly are more complicated.
2 Casting barrel: A layer of approximately 2 mm thick alloy is centrifugally cast on the inner wall of the barrel, and then the required inner diameter of the barrel is obtained by grinding. The alloy layer is well bonded to the base of the barrel, and the bonding along the axial length of the barrel is relatively uniform, has no tendency to peel off, does not crack, has excellent sliding performance, and has high wear resistance. long life.
1) The longitudinal groove of the inner wall of the barrel feeding section is opened
In order to increase the solids transport rate, one method is to increase the coefficient of friction of the surface of the cylinder by solid transport theory. Another method is to increase the area of ​​the material at the feed port through the cross section perpendicular to the screw axis. The formation of a longitudinal groove in the inner wall of the barrel feeding section and the taper of the inner wall of the section of the feeding section near the feeding port are the specifics of the two methods.
2) Forced cooling feed section barrel
There is also a method to increase the amount of solids transported. It is to cool the feeding section barrel, the purpose is to keep the temperature of the material to be conveyed below the softening point or melting point, to avoid the appearance of the melt film to maintain the solid friction property of the material.
With the above method, the conveying efficiency is increased from 0.3 to 0.6, and the amount of extrusion is less sensitive to changes in head pressure.

Gearbox-for-Plastic-extruder

Gearbox for Plastic extruder
The screw is the heart of the extruder and is a key component of the extruder. The performance of the screw determines the productivity, plasticizing quality, dispersion of the filler, melt temperature, power consumption, etc. of the extruder. . It is the most important part of the extruder, which can directly affect the application range and production efficiency of the extruder. The rotation of the screw exerts an extreme pressure on the plastic. The plastic can move, pressurize and obtain some heat from the friction in the cylinder. The plastic is mixed and plasticized during the movement of the cylinder, and the viscous flow state The melt is shaped while being extruded to flow through the die to obtain the desired shape. Like the barrel, the screw is also made of a high strength, heat and corrosion resistant alloy.
Due to the variety of plastics, their properties are also different. Therefore, in actual operation, in order to adapt to different plastic processing needs, the types of screws required are different, and the structures are also different. In order to maximize the efficiency of the plastics to maximize transportation, extrusion, mixing and plasticization.

The picture shows several more common screws. The basic parameters indicating the characteristics of the screw include the following: diameter, aspect ratio, compression ratio, pitch, groove depth, helix angle, screw and barrel clearance, and the like. The most common screw diameter D is approximately 45 to 150 mm. As the screw diameter increases, the processing capacity of the extruder increases accordingly, and the productivity of the extruder is proportional to the square of the screw diameter D. The ratio of the effective length to the diameter of the working part of the screw (referred to as the aspect ratio, expressed as L/D) is usually 18~25. Large L/D can improve the material temperature distribution, facilitate the mixing and plasticization of plastics, and reduce leakage and backflow.

Gearbox for Plastic extruder

Gearbox for Plastic extruder Gearbox for Plastic extruder

Improve the production capacity of the extruder, the L/D large screw has strong adaptability and can be used for extrusion of various plastics; however, when the L/D is too large, the plastics will be degraded by the heating time and the screw When the self-weight increases, the free end flexes and sag, which easily causes the material to be scratched between the screw and the screw, and makes the manufacturing process difficult; the power consumption of the extruder is increased. A screw that is too short may cause poor plasticization of the kneading.
The half of the difference between the inner diameter of the barrel and the diameter of the screw is called the gap δ, which can affect the productivity of the extruder. As the δ increases, the productivity decreases. Usually, the control δ is preferably about 0.1 to 0.6 mm. δ is small, the material is subjected to a large shearing effect, which is beneficial to plasticization, but δ is too small, strong shearing action easily causes thermal mechanical degradation of the material, and at the same time, the screw is easily hung or rubbed against the wall of the cylinder, and When δ is too small, there is almost no leakage or backflow of the material, which affects the mixing of the melt to some extent.
The helix angle Φ is the angle between the thread and the cross section of the screw. As the Φ increases, the productivity of the extruder increases, but the shearing effect and the pressing force on the plastic are reduced. Usually, the helix angle is between 10° and 30 degrees. Between °, along the direction of the change of the length of the screw, often using an equidistant screw, taking the pitch equal to the diameter, the value of Φ is about 17 ° 41 '


The greater the compression ratio, the greater the compression ratio that the plastic receives. When the groove is shallow, it can produce a high shear rate for the plastic, which is beneficial to the heat transfer between the wall of the barrel and the material. The higher the material mixing and plasticizing efficiency, the lower the productivity; on the contrary, the groove is deep. The situation is just the opposite. Therefore, heat-sensitive materials (such as polyvinyl chloride) should be used with deep screw screws; for plastics with low melt viscosity and high thermal stability (such as polyamide), shallow screw screws should be used.

Gearbox for Plastic extruder
1. Segmentation of the screw
When the material moves forward along the screw, it undergoes changes in temperature, pressure, viscosity, etc. This change is different within the full length of the screw. According to the changing characteristics of the material, the screw can be divided into adding (sending) material segments and compressing. Segment and homogenization segment.
1. Three states of plastics and plastics
Plastics have two types of thermosetting and thermoplastic. After thermosetting plastics are molded and cured, they cannot be heated and melted. The thermoplastic molded article can be reheated and melted into other articles.
As the temperature changes, the thermoplastic produces a three-state change of glass state, high elastic state and viscous flow state. Repeated changes with temperature, the three states produce repeated changes.
a. Different characteristics of the polymer melt in the tri-state:
Glass state - plastic appears as a rigid solid; thermal motion energy is small, intermolecular force is large, deformation is mainly contributed by the deformation of the bond angle; after the external force is removed, the deformation is instantaneously restored, belonging to the general deformation.
Highly elastic state - plastic is a rubber-like substance; deformation is contributed by the orientation of the macromolecular stretch caused by the orientation of the segment, and the deformation value is large; after the external force is removed, the deformation can be recovered but time-dependent, which is a high elastic deformation.
Viscous flow state—plastics appear as highly viscous melts; thermal energy further intensifies the relative slip motion of chain molecules; deformation is irreversible and belongs to plastic deformation
b. Plastic processing and plastic tri-state:
Machinable in plastic glass. Stretch processing in high elastic state, such as wire drawing, pipe extrusion, blow molding and thermoforming. In the viscous flow state, it can be coated, rotomolded and injection molded.
When the temperature is higher than the viscous flow state, the plastic will thermally decompose, and when the temperature is lower than the glass state, the plastic will be embrittled. When the plastic temperature is higher than the viscous flow state or lower than the glass state, the thermoplastic tends to be seriously deteriorated and destroyed, so the two temperature zones should be avoided when processing or using the plastic product.

Gearbox for Plastic extruder

Gearbox for Plastic extruder

The door and windows profile is made of PVC powder. Plastic extruder Gearbox is widely used as window and door profile, as well as decorative material. With modern technology and optimized design, it has the property of high output capacity, long life and plastic evently.

Plastic extruder Gearbox is kind of production line is designed for extrusion of PVC plastic doos and windos profiles and cross-section communication cable pipes, Aluminum-plastic composite profiles, etc. It has stable plastification, high output, low sheering force, long life service and other advantages. PVC profiles can be used in the building industry and home or office.

Lubrication and cooling, heating

Gears and bearings are lubricated with oil pools and splashes. In addition to splash lubrication, ZLYJ series hard surface gearbox and above bearings have been added to the oil pump lubrication system for forced circulation lubrication.

The lubricating oil grade is medium-grade pressure gear oil N220 or other high-quality skating oil with similar viscosity.

When the ambient temperature is lower than 0 °C, an electric heating pipe is added to the oil pool to preheat the lubricating oil.

When the ambient temperature is higher than 35 °C, our company performs heat balance calculation according to the temperature value provided by the user to determine whether to increase the cooling device.

Plastic extruder GearboxPlastic extruder Gearbox

 

ZLYJ series cylindrical bevel gearbox Hardened gearbox model:

Specifications are: ZLYJ112, 133, 146, 173, 200, 225, 250, 280, 315, 330, 375, 420, 450; SJY224, 250, 280, 315; ZSYJ315, 375, 395, 420, 450, 560; 6E , 7E, 8E, 9E, 10E, 12E, 15E, JHM and other plastic and rubber industry-specific gearbox (can be customized for various non-standard large gearboxs).

Single screw extruder Single screw plastic extruder for plastic extruder machine

 

With Best Regards,
Cherry Zhang ( Sales Department; Miss. )   
NER GROUP CO.,LIMITED
Yantai Bonway Manufacturer Co., Ltd                                      
Tel:+86-535-6330966
Mobile:+86-18865558975
www.planetary-gearbox.com
https://twitter.com/gearboxmotor 
https://www.facebook.com/sogears1993
Viber/Line/Whatsapp/Wechat: 008618865558975   
E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.; Skepy ID:Live:cherry_3053
Add:No.5 Wanshoushan Road Yantai city Shandong Province, China

 

Date

09 September 2019

Tags

Helical gear

 sogears manufacturing

The best service from our transmission drive expert to your inbox directly.

Get in Touch

NER GROUP CO.,LIMITED

ANo.5 Wanshoushan Road
Yantai, Shandong,China

T+86 535 6330966

W+86 185 63806647