Installation Requirements of Screw Conveyor

Installation Requirements of Screw Conveyor

1. The foundation of screw conveyor should be completed 20 days early before installing screw conveyor so that it can make foundation solid and reliable and keep the spiral machine from subsidence or deformation, to ensure there is sufficient stability when screw machine is running. 

2. The casing assembly shall meet the following requirements: 

(1)Longitudinal straightness tolerance accounts for 1/1000 length, full-length straightness tolerance is 3mm. 

(2)Lateral straightness tolerance accounts for 1/5000 width. 

(3)The gap on both sides of the inner wall of casing and screw shaft should be equal, its tolerance is 2mm, the bottom of the gap tolerance also is 2mm. 

(4)The casing joints should be tight fitting. 

(5)The casing and frame should contact well. 

3. The tolerance between shaft and bearing center line registration is 0.5mm. 

4. The inner surface of the two adjacent casing, their mutual joints may not have obviously shifted. 

5. The foundation bolts should be tightened after screw machine sections have adjusted well. 

6. The low-speed shaft of driving device and forward shaft of screw machine should be in a unified axis. 

7. It should be welded inlet and outlet after the whole machine is installed well if they require site installation.

The key points for screw conveyor selection

The key points for screw conveyor selection

1.Conveyor capacity

Screw conveyor conveying capacity refers to the amount of material per unit time.Users should consider whether the conveyor can support the use of other production equipment before design in order to design a reasonable conveyor model.

2.Conveying speed

Conveying speed can improve the transmission capacity. For conveyor which adopts chain as traction, the transporting speed should not be too fast, in order to prevent the power load increasing.

3.Component dimensions

The component dimensions of conveyor includes conveyor trough width or pipe diameter , etc. Which directly affect the transmission capacity of screw conveyor.

4.Conveyor length and inclination

Conveyor length and inclination directly affects the total resistance and required power of the conveyor. Screw conveyors installation can be level and inclined, so please let us know the using condition when select the model.

5.Screw conveyor motors

Motor selection can be speed controlled motor or general motor to control the conveying speed and throughput per hour.

6.Others

Whether hopper should be considered in the inlet or not,as well as the feeding hopper size.

Why Is Screw Conveyor Blade Damaged

Why Is Screw Conveyor Blade Damaged

During application of screw conveyor, it’s hard to avoid damaging screw blade. But do you have a better understanding about the reasons of screw conveyor blade damage? Today we will discuss it.

The most easily worn parts are hanging bearing, head or tail of screw conveyor, screw blade. Apart from temperature, environment and material, structure and human factors can also cause the screw blade. Then we will analyze the reasons why screw blade damages.

When the screw conveyor occurs blocking phenomenon in the outlet, it will cause screw blade damage. At this time, users can make the machine in a lower speed running. Sometime, when this machine conveys life garbage or organic plant, it also will lead to damage of screw blade.

In addition, the edge of screw blade is easier to be worn. Generally, if screw blade is far away from the axis of rotation, it will suffer the larger force and generate more cracks.

 

Never Do Like This, Or Screw Conveyor Will be Damaged

Never Do Like This, Or Screw Conveyor Will be Damaged

Why does your screw conveyor always exist problems? Due to that it has bad quality? It doesn't always like this. Sometimes, wrong operation way will also lead to the screw conveyor damage. After reading this article, maybe you will change your mind. And hope users can adopt right operation way.

Wrong operation ways are as follows:

1.Always open the upper cover during operation

It is prohibited that users open upper cover of screw conveyor during running, even if users want to observe running situation. If there are some impurities falling into screw conveyor when running machine, it will damage machine easily.

2.Never clean  residual material timely after using

It will shorten lifespan of screw conveyor if the residual material sticky or corrosive, and the blade and shaft will be corroded.

3.Never add lubricating oil to bearing

Users had better add lubricating oil to bearing regularly or it will affect the rotation of shaft because dust can make the lubricating oil become viscous.

4.Stop shaft rotating compulsively after shutting down the screw conveyor

This kind of behavior is bad for shaft of screw conveyor and vibration motor.Users had better stop the screw conveyor naturally.

•  

Daily Maintenance for Screw Conveyor

Daily Maintenance for Screw Conveyor

In order to prolong lifespan of screw conveyor,we should pay much attention to its daily maintenance.Here we will introduce you this kind of knowledge from 4 aspects.

Screw conveyor is bulk material handling equipment, which usually consists of a tube containing either a spiral blade coiled around a shaft (sometimes called an auger), driven at one end and held at the other, it is widely used in chemical, metallurgy, paper making, and construction industries, etc. Below you will see its daily maintenance methods:

1. When operate the screw conveyor, bearings, gears and transmission chain should be added lubricating oil regularly.

2. After machine stops, the spiral blade wear condition should be checked, if wears seriously, please repair welding.

3. The conveying capacity can not be overloaded, or the material can’t be discharged which will cause the screw axis bends and box damages.

4.During the operation of screw conveyor, any shrill noise, please open the cover and check, eliminate the noise timely.

Hope above mentioned maintenance will be helpful!

Blockage of Screw Conveyors

Blockage of Screw Conveyors

Blocking problem is the most common fault of screw conveyor which will affect the normal production. So how to address the blockage problem? This article will analysis this kind of problem and give some useful advice.

Since screw conveyor conveying space is small and it is sensitive to material, intertwining phenomenon is easy to occur when screw shaft rotates, blockage occurs in the place of hanging bearing. So blocking problem is the most common fault of screw conveyor which will affect production and increase power consumption, even the motor will burn out and screw shaft twist off which will affect the normal production. Blocking problem is caused by many reasons, we can take measures to avoid this problems:

1. Select reasonable screw conveyor technical parameters, for example, if using low speed screw conveyor the rotating speed can not be too fast.

2. Carry out the operation procedures strictly, non-load start-up and stop to ensure continuous evenly material feeding. 

3. Increase the outlet or extend the chute end dimension to solve the problem of unsmooth discharging or can not discharge material timely .At the same time, you can also install a section of reversed screw blade to avoid blocking. 

4. Clean up the material inside the screw conveyor in order to prevent big impurity or fibrous material enter into the screw conveyor and occurs blocking.

 

5. Reduce the transverse dimensions of intermediate bearing as much as possible in order to reduce the possibility of material passing through the intermediate bearing.

6. Install a level sensor and blockage sensor which can achieve the purpose of automatic control and alarm. 

The Reasons Why Screw shaft of Screw Conveyors Stops Rotating

The Reasons Why Screw shaft of Screw Conveyors Stops Rotating

Generally, if screw shaft of screw conveyors stops rotating, it mainly caused by the following three reasons:

 

1. The size of conveying material is too big and can't pass through the intermediate bearing, material resistance here is too big which will lead to motor overload and stop operation. Then you must clean up the material inside the screw conveyors .

2. The place of intermediate bearing resistance is large, sealing damages. Material will go into the bearing which will lead to bearing stops rotation or bearing damages.

 

3. Bearing of gear motor burns out.

If the reducer bearing temperature rises too fast after start-up and along with abnormal noise and reducer vibration, at this time, you should stop the machine quickly and the reason may be caused by the following aspects:

1) If the reducer output shaft bearing temperature is high ,but input shaft bearing temperature is normal. This is because the screw shaft centerline offsets or reducer output shaft bearing damages, or head and tail bearing loosens. Here you need to loosen the coupling between reducer output shaft screw shaft, correct and install.

2) If the bearing temperature of reducer output shaft is normal, but input shaft temperature is high. This is because the motor fixed components loosen or reducer output shaft bearing damages, you need to loosen the coupling between reducer input shaft and the motor, correct and install.

3) If both of reducer output and input bearing temperature are too high. This is due to the loosening of fixed bolts on reducer or both ends of reducer bearing burn out, here you need to loosen the coupling on both sides of reducer ,correct and install.

 

Debugging of Screw Conveyor

Debugging of Screw Conveyor

All the hanging bearings of screw conveyor should be hanging on the connecting shaft reliably without stuck and bending of screw. When installation, adjusting the gaskets number of hanging bearing to make no gap in subdivision surface while a proper radial gap between bearings and connecting shaft.

 

Hanging bearing should be installed in the center of connecting shaft, the distance between end face and two screw pipes should be over 10mm when D≦400mm and over 20mm when D≧500mm.

To adjust the accumulative error between chassis and screw, there should be padding asbestos lining between the flange of the chassis when installation. Padding waterproof canvas between chassis and cover according to the requirements for sealing.

 

When the difference of center heights of driving gear reducer shaft at low speed and screw conveyor is too much, using the gaskets to adjust the height of driving unit.

 

When no-loading running, if there is oil leakage phenomenon, removing the bearing and adjusting the tightness of spring in sealing ring until no leakage.

When no-loading running, overheating of hanging bearing indicates the installation position of hanging bearing is improper which leads the locking of connecting shaft, there should be loosing the fasten bolt and adjusting the position of hanging bearing.