Vari-Wave JIG

Vari-Wave JIG
(Variable Wave Type JIG)
Doc. 07-010
NAGATA ENGINEERING CO., LTD.

Introduction
Since 1932, Nagata Seisakusho had supplied more than 400 sets of Nagata
Jig, and Nagata Engineering took over Nagata Seisakusho’s technology and
business in 2004.
Nagata Jig, which is the Air Pulsated Jig, has been widely adopted as a main
coal washer, because it has technical and economical advantages such as
large capacity, low running costs and long life.
Nevertheless, the increasing demand of fuel coal requires higher productivity
and efficiency of Air Pulsated Jig. As the representative Air Pulsated Jig,
there are the Baum type Jig that the air chamber is equipped side bed, and
the air chamber under bed type Jig.
Baum type Jig Air Chamber Under Bed type Jig
In 1980, we had proved the uniformity of strength of pulsation in wash-box
with large scale V-shaped testing Jig having 5.0m width of jigging chamber.
The V-shaped Baum type having 3.75m and 3.6m width of jigging chamber
are now in commercial operation in Japan and China.
Furthermore, we had developed the Vari-wave Jig that the wave pattern in
the jigging chamber can be changed easy such as from sinusoidal wave to
trapezoidal wave.
We introduce the Nagata’s Variwave Jig, hereinafter.
Nagata Engineering Co., Ltd.

Principle of Separation
The coals are inserted in U- tube of one
side which is equipped screen plate, and
the water is inserted in U-tube until the
coal hides completely. When the water is
jigged by the piston, both the coal and
water are jigged. By the repetition of
this jigging, heavy coal particle gradually
transfers from upper layer to lower layer.
The arrangement of heavy coal particle
and light coal particle is stratified to the
order of specific gravity completely by jigging
of specified number. By dividing the coal
stratification at the height of decided point,
stratification of coal is divided to light gravity
coal “low ash” and heavy gravity coal “high ash”.
Air Pulsated JIG had been commercialized with Figure of Principle
applying this principle air movement.
Characteristic of Air Pulsated Jig
Cheep Running Cost
Large Capacity
Easy Maintenance
Wide Adaptability
Long Life

Separating Machanism
For Air Pulsated JIG, it is important that the following factor is controlled
as the separating machine. The factors are as follows.
(1) Necessary condition in order that the coal particle is stratified
Stratification condition:Coal feed value, Water feed value, Jigging number,
M
Service Hopper
Chain Feeder
Constant Volumetric
Feeder (VVVF Control)
Optimum wave pattern
Stratification condition changes by specific gravity constitution and diameter
of coal particle.
Air Pulsated JIG also is transport machine because it moves the coal while
causing the particle stratification.
Therefore, transport capacity and separating accuracy are inverse proportion.
(2) Exact separation of stratified particle group, and discharge
If Air Pulsated JIG can not exactly separate stratified particle group as 2 products,
the JIG can not keep the separating accuracy.
Stratification Conditions ;
Coal feed value, Water feed value, Jigging number, Optimum wave pattern
Raw Coal Feed System
Float
Star Wheel
(VVVF Control)
Slide Gate Driven
by Electric Motor
(Manual Control)
M
M
Refuse
Coal
Figure 7 Separation Mechanism of Air Pulsated Jig
Discharge System

(3) The automatic control system
(a)Refuse Ejector:the device in order to separate the coal bed with appropriate level.
Conventionally model Discharge control model
Turn gate type Star-wheel type
Effect: stability of refuse bed by the improvement of discharge efficiency of refuse
Control Method ;
Component of Control System
The float, which detects the refuse height, is repeated floating and subsidence with coal
particle by jigging, and the subsidence point of float is in the specific gravity position
(separated specific gravity) of the coal bed equivalent to float specific gravity.
The float position, where flatters the coal bed thickness, is converted to electrical signal,
and the refuse discharge device is controlled automatically. The refuse discharge value
is controlled automatically by proportion or PID control.

6
3
0
Optimum Wave Pattern for Separating
Performance of JIG is influenced with many factors !
However, Optimum wave pattern that is one of the stratification condition has
not been established yet.
★What is optimum wave pattern?
Necessary to develop the Wave Pattern Control System !
The wave pattern of Air pulsated JIG is divided as follows.
Quick-up-slow-down Slow-up-quick-down Trapezoidal
0 180゜ 360゜ 0 180゜ 360゜ 0 180゜
As for the optimum wave pattern, is it one of them on separating in above wave
pattern ? Can the optimum wave pattern make it optionally?
Thereupon, we had made the actual wave pattern by pilot device, in order to confirm
the separating accuracy etc. and result was got as follows.
Pilot Plant for JIG Experiment Result of Wave Pattern
Trapezoidal wave pattern is excellent in separating most
◆The comparison of "Capacity/Imperfect" of Trapezoidal wave pattern and other waves
In case of same capacity :Best imperfect
In case of same imperfect:Large capacity
Trapezoidal Wave Pattern=Optimum Wave
360゜

Realization of Vari-wave JIG
(1)Factor that materializes the variable wave
★Concomitant use of high pressure air and low pressure air
★Valve unit driven by air cylinder & electromagnetic valve
★Sequential control of valve timing (Opening and closing )
(2)Modification from U-type JIG to Variable Wave JIG
Rotary Valve ⇒ Air Flat Valve Unit
(3) Opening and closing timing and theoretic wave pattern of Air Flat Valve
The pulsated wave pattern such as the above figure is obtained theoretically when the
air flat valve is opened and closed with the timing like the port line figure. The wave
pattern can make an optional wave pattern by the introduction of the control system
furthermore, although it is the wave pattern of a trapezoid in the pattern.

Easy Changing Wave by Air Flat Valve System!
By easy operation of Touch-panel, Air Flat Valve system makes the variable
wave. Additionally, the wave pattern can be changed to usage pattern
quickly without stopping operation.
Change of the wave pattern is very easy.
Various wave is able to make it easily
TOUCH PANEL
Sinusoidal
Trapezoidal

Constitution of Vari-wave JIG
System Diagram of Vari-wave JIG
SERVICE
HOPPER
Raw Coal
HIGH PRESSURE
INLET VALVE
LOW PRESSURE
INLET VALVE
FEEDER
SV
EXHAUST
SV
SV
1st VESSEL
EXHAUST VALVE
REFUSE HEIGHT
TRANSMITTER
M M
SLIDE GATE
WAVE MONITOR
2nd VESSEL
M
STARWHEEL
VVVF CONTROL
3.7KWx4P
Refuse Middling
AIR CHAMBER AND VALVE
SLIDE GATE
M
3.7KWx4P
M
RECEIVER
EXISTING
EMISSION VALVE
Clean Coal
LOW PRESSURE
BLOWER
EXISTING
M
RECEIVER
EMISSION VALVE
M
HIGH PRESSURE
BLOWER
140KWx2P
CONTROL PANEL
22KWX4P
M
COMPRESSOR

Delivery of Vari-wave JIG
Customer:Ikeshima Colliery, Japan
Capacity :300t/h~400t/h
Quantity :1set
Customer:Kushiro Coal Mine, Japan
Capacity :290t/h
Quantity :3sets
Customer:Panjiang, China Customer:Cuaong, Vietnam
Capacity :125t/h Capacity :290t/h
Quantity :1set Quantity :3sets
Customer:Ombilin, Indonesia
Capacity :200t/h
Quantity :1set

LINES OF BUSINESS
COAL PREPARATION PLANT
● Coal Preparation Engineering
● Variable Wave JIG
● Heavy Medium Separator
INDUSTRIAL MACHINERIES
● Pig Casting Machine
● Mixers [ Pug-mil, Paddle Mixer ]
● Feeders [ Belt Feeder, Table Feeder ]
● Ladle tilting Machine
● Belt Conveyor System Engineering
ENVIRONMENENT INDUSTRIAL MACHINERIES
● Mould Conveyor for melting Slag
● Oil Agglomeration System
● Specific Gravity Separator
NAGATA ENGINEERING CO., LTD.
Head Office:
10-1, Kitaminato-machi, Wakamatsu-ku, Kitakyushu-shi,
Fukuoka, 808-0027 Japan
TEL: 81-93-761-3754
FAX: 81-93-761-5454
URL: http://www.nagata-kit.co.jp
Revise 2007.06
Print 2007.06