YOKOI KIKAI KOSAKUSHO HOPE CRU-10 User manual

HG0T063E
HOPE C R U
CRUCIBLE SELF REGENERATIVE
GAS BURNER
HANDLING MANURLS
YOKOI KIKAI KOSAKUSHO CO., LTD.
Head Office:
2720-1, Oboraguchi, Nakashidami, Moriyama-ku
Nagoya 463, Japan
Tel: [phone] Fax: [phone]

1
TABLE OF CONTENTS
1．TBLE OF CONTENTS ・・・・1
2．Inspection of Product and Accessories, and Outline and・Features ・・・・2
3．Specification ・・・・3
4．Actuator Auto Switch ・・・・4
5．Pressure Switch for Assist Air ・・・・5
6．Installation ・・・・6
7．Piping・.Monitoring of Main Flame ・・・・7
8．Operation Timing of the Valve ・・・・8
9．Flow sheet ・・・・9
10．Test Operation ・・・・10
11．Inspection・Precautions ・・・・11
12．Replacement of Ceramic Balls ・・・・12
13．Overhaul Burner・Replacement ・・・・13
14．Spare Parts・Warning Plate ・・・・14
15．Troubleshooting ・・・・15
16．Structural drawing ・・・・16

2
Thank you for your selection of CRUCIBLE SELF REGENERATIVE GAS BURNER
Type CRU Please carefully read this instruction manual in order for you to be fully
satisfied with the performance of this burner and to secure the safety in operation,
maintenance and inspection. Also, please be sure to deliver this instruction manual to
the end user, as well as to the constructor.
Inspection
Check the model and type of the burner, the voltage of the solenoid valve, the part No. of the
auto switch, etc. to confirm that they are exactly what you have ordered. Also, check for
damage, etc, due to transportation.
Outline
Our CRU Crucible Self-Regenerative Gas Burner is a self-regenerative gas burner we have newly developed for
crucibles.
To enable combustion in a ring-shaped narrow space, the direction of the combustion flame is alternately
switched to clockwise/counterclockwise during the combustion. As the flame does not contact the crucible
directly, the life of the crucible is extended and the temperature distribution is improved.
Although this burner was developed for crucibles, it can be also applicable to other crucible-shaped furnaces
(e.g., pit-type furnaces, bell-type furnaces) with the expectations of the same effect.
Features
１)Since the regenerative combustion system is integrated into one burner, cost can be
reduced.
２)The energy-saving effect is so large that CO2emission can be reduced substantially.
３)Since there is no portion of extremely high temperature within the flame, very favorable
temperature distribution can be obtained.
４)Since highly luminous flame is obtained, the radiant heat transfer effect can be improved.
５)The replacement/cleaning of the regenerator can be conducted easily.
６)As the flame does not contact the crucible directly, the life of the crucible is extended.
７)As the flame direction is alternately switched to clockwise/counterclockwise, the local heat is prevented
and therefore the temperature distribution is improved.
８)As the pressure loss of the burner is small, no exhaust fan is required, which leads to cost reduction.

3
Specification
Type Main
Cap kw
Pilot
Cap. kw
Main
Air Flow
N㎥/h
Pilot
Air Flow
N㎥/h
Assist Air
Flow
N㎥/h
CRU-10 100 7 200 7.3 2.7
CRU-20 180 7 320 7.3 5.0
Standard Pressure
Main air pressure 4kPa(CRU-10)，5kPa(CRU-20)
Gas pressure 10kPa
Pilot Gas pressure 6kPa
Air pressure for driving the actuator 0.3MPa
Assist Air 0.1MPa
Weight
Type Burner Mass
kg
Ceramics Ball
Masskg
Ceramics Ball Size
Inch
CRU-10 250 50 1/2
CRU-20 410 90 1/2
Ceramic balls are packaged in a paper bag, which weighs 25kg. Order placement is acceptable
in units of 25kg.

4
Actuator
Burner Type CRU-10 CRU-20
Actuator Type CDRQ2B20－01 CDRQ2B40－01
Air consumption l/min 0.2×2 0.6×2
Standard Pressure 0.3 MPa
Auto Switch
T
y
p
e
Special
function
Electrical
entry
With
indicator
light
2-wire 24V 12V
Solid
State
Auto
Switch
─Grommet
Indicator
light Wiring type
Load voltage
DC AC
─D-M9BW Relay,PLC
Auto switch model Applicable
load
The auto switch is attached to the actuator for operational detection.
The length of the lead wire is 0.5m.
Auto switch Internal circuit
D-M9BW (V)（Sink input mode）D-M9BW (V) （Source input mode）

5
Pressure switch for assist air
Set the pressure switch by using the following method so that it can be ON when assist air is supplied and OFF
when assist air is not supplied:

6
Installation
１)When separating the burner tile from the pilot burner body, remove the body first.
２)To facilitate the replacement of the heat storage body, mount so that the selector valve is
vertically.
３)Back up the outer surface of the burner tile, particularly the lower portion of the outer
surface, with fire brick, castable refractory or the like to prevent the burner tile from
dropping.
４)When mounting the burner to the furnace body, fill the gap between the mounting port
and the burner tile with fire mortar or the like for fixing.
５)Install the burner so that air can be taken in from below and air is exhausted from above.
６)Provide a space behind the burner enough for pulling out the burner gun from the burner
for the maintenance purpose.

7
Piping
１)Direct good care to the inside of the pipe not to leave seal tape fractions, bond,
cutting chips, etc. there which may cause malfunction of the solenoid valve,
governor, valve, etc.
２)In connecting the pipes, provide pipe support in proper positions to prevent the
application of any excess force
３)Attach an MO type orifice flow meter to each piping. Also, provide a straight pipe
segment that is as long as 5 times or more of the pipe diameter before and behind each
orifice flow meter
４)Use the air free from drain, mist, etc. for driving the actuator and assist air the
selector valve
５)Since high-temperature gas containing a large amount of moisture passes through the
exhaust side piping, it is advisable to take countermeasures against corrosion, such as
draining.
６)Since the exhaust side piping is held at a high temperature, seclude the piping from
the direct contact by human bodies.
７)In mounting the gas regulating valve, the butterfly damper, the orifice flow meter, etc.,
position them to be easy for adjustment.
８)The gas regulating valve and the butterfly damper should be lockable
９)The flow direction of the orifice flow meter is fixed. Be careful not to turn around IN
and OUT directions
１０）Mount the gas solenoid valve as close as possible to the burner inlet.

8
Main Flame Monitoring
In inspecting the main flame, view the flame in the arrow directions from the 2
inspection holes as shown in the below figure.
To prevent heat transfer from the furnace wall, air-purge from the mounting part of Ultra Vision.
Set the distance from Ultra Vision to the flame monitoring position to within 1.5m.
Valve Operation Timing
●Selector valve
Operate the selector valve at every 15 sec. Be sure to turn ON/OFF the power supply to both the intake
valve and the exhaust valve together. Normally, at the time of combustion, never turn the intake valve
and the exhaust valve ON and OFF, respectively, or reversely OFF and ON, respectively. However, at
the time of temperature control, this turning ON/OFF is not simultaneous for these two valves.
●3-port valve for assist air
Turn ON/OFF this valve at every 15 sec in the same way as the selector valve.
●Operation of the main gas solenoid valve when the crucible temperature is low
As a characteristic of the selector valve, when the selector valve is switched, the “gas-rich”
phenomenon occurs, making the combustion unstable. To counter this problem, close the main gas
solenoid valve at the same timing as that of the selector valve and 3-port valve, and open the valve
with a delay of one sec for the initial 10 min from combustion start or until the crucible
temperature goes up to 500℃only as a guide.
Thereafter, perform the normal main valve operation (always opened).
４５°
４５°

9
●Operation of the selector valve and main gas solenoid valve at the time of temperature control
To minimize the fall of the crucible temperature when the main air enters the crucible at the time of
temperature control (gas OFF), operate the intake valve alone in reverse to the exhaust valve and the
3-port valve (Set the intake valve OFF [ON] when the exhaust valve and the 3-port valve are ON
[OFF]).
If the selector valve is switched upon the opening of the main gas solenoid valve, as this cause the
“gas-rich” phenomenon, delay the timing of the main gas solenoid valve open by one sec.