1. Installation Procedure for Scraper Conveyors

Basic retesting → Installation of head and tail assemblies → Bracket Installation → Airframe installation → Scraper and Chain Installation

(1) Re‑measure the foundation dimensions and address any issues promptly. Upon completion of the foundation re‑measurement, the equipment supports may be welded to the embedded steel plates in the foundation. The allowable deviations for the foundation dimensions and positioning in this project are as follows:

( 2 ) Installation of the head and tail assemblies

1) The head and tail sections shall be securely mounted on the foundation to ensure smooth operation and prevent body sway during machine operation.

2) The head and tail must be aligned, and the two wheel axles must remain parallel to prevent the scraper chain from deviating during operation.

(3) Installation of the support frame

When installing the brackets, be sure to use a level to ensure they are perfectly horizontal, and then weld them securely in place.

(4) Fuselage Installation

1) Assembly shall proceed in the sequential order indicated by the continuous numbering marked on each section.

2) During installation, ensure that the casing is both level and plumb. In particular, verify that the base plates are flush when joined, and that the inner flanges of each fuselage section are aligned squarely and tightly fitted. Additionally, the flange opening at the front of the scraper chain’s travel path should be slightly lower, allowing for a downward misalignment of 0.5 to 1 mm in the direction of motion. The side panels must not exhibit lateral misalignment to prevent jamming or impact during scraper chain operation.

3) After the conveyor frame is installed, its straightness shall meet the following requirements:

When the total length of the conveyor is 30 m or less, the straightness tolerance is 5 mm.

When the total length of the conveyor exceeds 30 m, the straightness tolerance is 8 mm.

The straightness measurement method is shown in the figure below: Straightness = max − min.

(5) Installation of the scraper chain

1) Before installation, the scraper chain should be inspected to ensure that its joints rotate smoothly. If rotation is stiff, the chain must be disassembled, and the pin shafts and link holes should be polished with sandpaper. Do not apply any lubricants or greases; only proceed with installation once smooth operation has been confirmed.

2) Before installing the scraper chain, first open the head and tail end covers as well as the inspection cover, and adjust the tail shaft to the foremost position facing the head.

3) Use two thin steel cables to pull from the head end to the tail end. First, install the lower scraper chain; at the lower tail end, secure the first set of scraper chains with the steel cable, then pull the lower cable through the head end to draw the first set of scraper chains into place. Next, connect another set to the first, and continue pulling the lower cable through the head end to install the second set of scraper chains. Proceed sequentially, installing each set of scraper chains one by one. When the lower steel cable is pulled out from the head end, the lower scraper chain will be fully installed. Then, install the upper scraper chain using the same procedure as for the lower scraper chain.

4) When installing the scraper chains, note the following: the upper scraper chain should be oriented in the opposite direction to the lower scraper chain. For example, when the head rotates clockwise, the lower scraper chain should have its small end facing the head and its large end facing the tail, while the upper scraper chain should have its small end facing the tail and its large end facing the head.

5) Connecting the scraper chain. First, join the upper and lower sections of the scraper chain at the head end. Then, at the tail end, pull either the upper or lower section of the scraper chain taut, adjust it to the proper length, and finally secure the connection at the tail.

6) When connecting the scraper chain, the elastic snap ring must be securely fastened or the pin retaining ring must be firmly welded to prevent the pin from coming loose during operation, which could lead to a serious accident.

(6) Installation of the Drive Unit

1) The motor reducer and the transmission mechanism shall be securely mounted. During installation, the reducer’s output shaft must be parallel to the head pulley’s output shaft.

2) The center planes of the large and small sprockets shall coincide, with a deviation not exceeding 2/1000 of the center distance between the two sprockets.

3) After the drive unit has been aligned, it shall be securely fastened to the foundation to ensure smooth equipment operation.

(7) Debugging

1) Preparatory Work

Except at the scraper chain pin joints, all screws, slide rails, bearings, transmission components, and the interior of the reducer shall be lubricated in accordance with the equipment’s accompanying technical documentation. Remove any debris from inside the machine body. Check the chain tension as follows: manually rotate the coupling between the motor and the reducer to straighten the lower section of the chain, then lift the scraper chain at the disengaged portion of the head pulley; if you can raise it by 50–100 mm, the tension is correct.

2) No-load test. Once the aforementioned preparatory work is completed, a no-load trial run of the individual unit may be conducted.

(8) Personnel Allocation: One fitter at the head end and one at the tail end, plus one electrician.

(9) Jogging operations shall be performed for no fewer than three full strokes. First, initiate jogging; during jogging, the operator at the head end must verify that the head pulley is rotating in the correct direction. If incorrect, the electrician shall reverse the motor’s phase sequence. Then, jog again. The head-end observer shall inspect, from the head end, how the scraper chain wraps around the head pulley; if any arching of the scraper chain is detected, adjust the tail‑end screw to further tension the chain until the condition shown in the figure above is achieved. Continue jogging tests; the tail‑end observer shall, from the tail‑end cover plate, check whether the scraper chain is running off‑center. If so, adjust the screw on the affected side to correct the misalignment.

1) If none of the aforementioned abnormal conditions occur, a no‑load trial run may be conducted. The no‑load trial run shall meet the following requirements: the scraper chain must run in the prescribed direction; engagement at the head pulley must be smooth, and there should be no chain jamming or skipping upon leaving the head pulley; the scraper chain must operate smoothly, with no side tracking or unusual squealing; the permissible deviation in operating speed is ±5% of the rated speed; and continuous operation at the rated speed must last for at least 2 hours.

2) Load test. After the no-load trial run is completed, a load trial run may be conducted.

The conveyor must not be started under full load. Feeding should be uniform and continuous, with a gradual increase in material input; abrupt, large‑volume loading is prohibited. During the trial run, carefully monitor for any material leakage during transport and ensure smooth discharge; address any issues promptly. During operation, the temperature rise of the main unit’s bearings shall not exceed 40°C. The loaded trial run shall last 8 hours.