Technical_reference - 第93页

Technical Service Manual 93 Revision Dat e: August 2004 BOARD SUPPORT Board Support is : ! Standard, (installed on all ovens ) ) An option, (NOT installed on all ovens ) The Boar d Support is a prec ision flex ible me ta…

Technical Service Manual 92 Revision Date: August 2004

INITIAL SETUP

The following process is done at the time the oven is built. It should be required only after repair or service of the

Autolube System.

1. Locate the lubrication reservoir. ( see illustration above )

2. Fill the reservoir with the lubricant, Darmex (Vitronics-Soltec P/N 1227204). (Remove the cap and pour the lubrication

into the top of the reservoir.

3. Prime the lube system. Refer to the User Manual (Chain lubrication system setup) for details on how to prime the

system.

4. Priming the autolube system can take as much 6 hours depending on the size of the oven. The priming operation will not

shut-off automatically, therefore it MUST be monitored to prevent excess oil from dripping on the floor.

(During normal “Manual” & “Auto” Lube operations, the system does stop automatically)

NORMAL OPERATION

First, refer to Rail Chain Lubrication in the User Manual.

To perform a single manual lubrication of the conveyor chain:

1. Select manual lubrication in the Oven Control Software by clicking on the Oil cans Icon. The conveyor chain will run, and

lube oil will be applied at the rate of 1 drop per 3 feet of chain, for two complete cycles of the chain(s).

For automatic lubrication of the conveyor chain on a regular basis:

1. Select automatic lubrication in the Oven Control Software. Enter the desired lube frequency. (The default is 275.) This is

the number of chain cycles between lubes.

2. Enter the lubrication alarm count. (The default is 50.) This is an estimate of the number of lubrications contained in the

oil reservoir. Observe the amount of oil used for 50 oiling cycles and then adjust the number up or down depending on

the amount of oil remaining in the reservoir only after refilling the reservoir

In automatic mode, the lubrication process does not interrupt oven processing.

The chain will be lubed while there is product in the oven.

Avoid “over oiling” and getting lubricant on the conveyor chain transport pins. Apply the lubricant sparingly, do not soak

the chain or apply so much that the lubricant drips off. Make sure the factory exhaust system is on and operating

properly because some fumes may be created once the heaters are turned on

ALARMS:

Þ When the alarm count for lubrications has been reached a “Low Oil Message” will be displayed at the bottom of the

Operating Screen. Automatic or manual lubrication will not be permitted until the reservoir has been filled, and the

alarm reset.

This is the best time to adjust the cycles between lubes and/or the number of lubes before “Low Oil Message alarm.

Technical Service Manual 93 Revision Date: August 2004

BOARD SUPPORT

Board Support is:

! Standard, (installed on all ovens) ) An option, (NOT installed on all ovens)

The Board Support is a precision flexible metal belt carrying vertical pins positioned under the Printed Circuit Board during

the process through the oven. The adjustment of the location of the belt under the product is driven by an electric motor.

A selector switch on the operator’s panel operates the motor. If the Board Support is not required for a particular product,

it can be positioned between the fixed rail pin chain. The free space required is 8 mm on one side of the Printed Circuit

Board, facing the Operator.

There must be a clear space of 3mm (1/8 inch) on the bottom side of the PCB for the pins of the CBS.

CONTROLLED COOLING

Controlled Cooling is:

!Standard, (installed on all ovens) )An option, (NOT installed on all ovens)

DESCRIPTION:

The Controlled Cooling System consists of two independent cooling circuits on the oven. The cooling circuits operate by

recirculating a cooling fluid through gas-to-liquid heat exchangers in the cooling cells of the oven and through liquid-to-air

heat exchangers external to the process tunnel of the oven. By adjusting the liquid temperature of the coolant with a

circulation heater and by controlling the external cooling fan, the gas temperature in the cooling cells of the oven can be

controlled.

CONTROL:

The operator interface for adjusting controlled cooling zone setpoints is the same as for the heated zones of the oven. A

controlled cooling equipped oven has two cooling cell setpoints, which can be changed by the operator within the Oven

Control Program. An oven with two cooling zones has a set point for each. An oven with three cooling zones has a set

point for the first and second cooling zones (the first cooling zone being the one closest to the heated section of the

oven). An oven with four cooling zones has a set point for the first and third zones.

OPERATION & PROCESS:

Controlled Cooling provides the ability to stabilize the temperatures in the cooling zones of the oven. It provides

compensation for factors such as changes in ambient temperature and product loading. It also allows the cooling zones

to reach a stable temperature much sooner than is possible with uncontrolled cooling, and ties the cooling zone

temperatures to the process ready condition of the oven.

The temperature range which is attainable for Controlled Cooling zones is influenced by many factors, including, but not

limited to, the following: heated zone set-points, conveyor type, conveyor speed, product loading, nitrogen flow settings,

machine exhaust, controlled exhaust setting, etc.

Technical Service Manual 94 Revision Date: August 2004

CONTROLLED EXHAUST SYSTEM (AIR ONLY OR OVENS EQUIPPED WITH AIR SWITCHING)

CONTROLLED EXHAUST SYSTEM (CES) (Air Mode)

This exhaust subsystem extracts heated gas directly from the oven chamber between the last heating zone and the first

cooling zone, minimizing the amount of heat and flux entering the cooling section of the oven. The result is product

cooling improvement and maintenance reduction in the Air Mode. It generates a controllable, positive exhaust flow and

does not depend on the facility exhaust for its operation.

A small amount of compressed air flows through a Venturi (mounted inside the Controlled Exhaust Tube) and creates a

negative pressure at the CES slot in the oven chamber. This draws gas out of the Oven Chamber. The oven chamber

exhaust flow rate is controlled by the amount of air supplied to the oven.

The cooling effect of the incoming compressed air causes an accumulation of flux condensate in the exhaust nozzle.

The nozzle requires periodic cleaning

INDIVIDUAL CELL INLETS

The “makeup” gas to replace the exhaust flow is supplied by the gas intakes of the individual Zones (cells). Additional

“makeup” enters the oven chambers at the “onload” and “offload” openings.

CES system is not used with N2 to minimize nitrogen consumption.