Fully automatic silo feeding system for EPS/EPP factory
A. Silo arrangement and specification
1. According to the material consumption, aging period and storage area, we calculate
the reasonable silo quantity, assigned to the appropriate equipments, ensure the rational
flow of silos.
2. Silo bag made of high strength nylon material. The joints are stitched in hemming with
multi-line sewing. It will prevent stratification of light and heavy materials, and it also
ensures the firmness of silos and longer service life.
3. Silo configuration (feeding box under the bottom of silo is working for shape molding
machine, the silos working for block machine will have a discharge valve at the bottom),
1.5m distance between two lines for piping and ventilation, ensure the good aging effect.
4. All silos are made of high-strength nylon material with no less than 50 mesh. The joints
and brackets are fixed with copper buckles. The stress of the four silo sides is even. There is
a support device at the bottom.
B. Pipes selection and piping specification
1. Feeding pipes will be Æ200 galvanized spiral tubes, pneumatic valve specially designed,
ensure the material moving without any obstructs.
2. Transmission pipes should be 1.6m above the ground, for easy cleaning and maintenance,
all pneumatic valves should be fixed on shelves.
3. Transmission pipes, shelves, suction pipes and machines should be tandem connected by
galvanized flat iron and ground connection.
4. In order to avoid the pipe blocking by misoperation, reserve the suction port with
corrugated tube, suction out the blocking by special blowers or feeding blowers.
C. Feeding pipe configuration and specification
1. Shape molding machine feeding will be integration module management. Module
with 28 holes with fast connectors, correct number for each silo, recognizable marks
for manual shifting.
2. Should be feed boxes for shape molding machine silos, box body with material blocks
filtering and cleaning functions, prevent the blocks get into shape molding machine,
filter with 12*12 SS mesh.
3. There are two ports on feeding box, connected to integration module by. Two SS tubes
connection between modules, backup for taking material from silos nearby temporarily.
Module and shape molding machine connected by Æ51 SS tubes, there will be an anti-
static soft tube with steel, for static release. Module/pipe shifting by anti-static soft tube
with steel connection.
4. The silos for block molding machine will work with pneumatic three-way valve, start
the silo you want on touch screen. All silos connected together, one line to pre-expander
secondary expansion device, the other line to block machine. Manual valves will control
open/close between pipes.
D.Elimination requirements for foaming agent (pentane)
Foaming agent (pentane) has bigger density than air, it will be easy to deposit at the
bottom of silo, not easily emitted. There should be no underground drain at the area
understand silo bottom. All electric wires should be protected by sleeves, and lights
and switches should be explosion-proof type. Good ventilation.
If there any exhaust blower, the motor of blower should be explosion-proof type. It is
recommended to install two pentane detectors at the bottom of silo respectively. When
the pentane concentration reaches a certain value, an alarm will be automatically issued.
The fan motor will automatically start to blow and discharge pentane to prevent fire.
E. Electric box, power cable installation specification
1. Control box should be located at a safe distance, independent layout, and easy operation.
2. All the lines in the access silo area are DC24V. All the lines adopt protective metal trunking
or PU sheath. The material level sensor has a fixed bracket and is firmly installed. The
connection adopts a PU tube sheath. All wire troughs and silo brackets are short-circuited
for grounding protection.
3. There is one 10.1’ touch screen for shape molding machine integrate plate, the other
10.1 screen will be worked for block machine, which will be close to block machine control
box, and one will be on pre-expander control box, the communication among screens will
be built, all screens data is consent.
4. Touch screen functions: expansion density set, status of each silo, warning for full silo,
warning for empty silo, aging time display for each silo, all data live updating.
5. Rotary material level switch working stably with reliable signal, will avoid misoperation
6. When actual material level is lower than lower sensor, system will send sound-light
alarming, reminder operator to shift silos, it will last all the time until operator shift the silo
and press the confirming button. And there also level sensors on shape molding machine
hoppers, machine will stop and alarming when there is no enough material. The defective
products will be prevented from feeding step.
1. Less labor cost, the whole system only need one operator start/stop system, no need
long-time monitoring the production.
2. Higher efficiency, electric components detects material level and control the valves
open/close, faster than human watching and manual shifting, greatly guaranteed the
supply of sufficient material and the simplification of the operating.
3. Easier operation: operator could check the status of stock inside silos at main
equipments, there will be more rational operations on main equipment for production.
4. More safe, whole process carried by machinery, rational method and suitable material
will prevent the failure and accident from manual misoperation.
5. Compatibility and forward-looking, this system could cooperate with the automation
upgrade of other equipments of customer's factory, and prepare for the development
of unmanned plant in future!