Attachment 8 - Natcom Burner Manual.pdf

Operation & Maintenance Manuals

OPM00 - Basic Principles- Version 2.1.c 1

NATCOM BURNER TECHNOLOGY

BASIC PRINCIPLES

Version 2.1

OPERATION AND MAINTENANCE MANUALS

OPM00 - Basic Principles- Version 2.1.c 2

CONTENT

1 INTRODUCTION

1.1 MIXING AIR AND FUEL TO MINIMIZE EXCESS AIR REQUIREMENT

1.2 STABILIZING AND SHAPING THE FLAME TO FIT THE FURNACE

1.3 CONTROLLING EMISSIONS OF POLLUTANTS AND PARTICULATE

2 OPERATING PRINCIPLE AND FEATURES OF THE NATCOM BURNER

OPM00 - Basic Principles- Version 2.1.c 3

1 INTRODUCTION: THE THREE MAIN FUNCTIONS OF A BURNER

1.1 MIXING AIR AND FUEL TO MINIMIZE EXCESS AIR REQUIREMENT

A burner is a mixer.

A burner’s primary function is to insure that the fuel is evenly mixed with air so that it is completely burnt within a limited flame volume. A burner is considered more efficient as the amount of excess air required for complete combustion within a given volume is lowered. The mixing power required to obtain the desired mixing rate comes from the summation of the combustion air flow pressure drop and the fuel flow pressure drop. These air and fuel pressure drops at a given volumetric flow rate provide the potential mixing power for a burner to accomplish its task. The flame volumetric heat generation of any burner is a function of its mixing capabilities: the better the mixing, the smaller the resulting flame will be.

1.2 STABILIZING AND SHAPING THE FLAME TO FIT THE FURNACE

As a second function, a burner must be able to ignite easily to generate a stable flame that, most importantly, fits the furnace geometry. As for the stabilization of the flame, it is generally performed without much difficulty by a bluff effect and/or a critical swirl effect. Flame shape can be described by its length-to-diameter ratio and is determined by the aerodynamics of the air and fuel injection pattern. The swirl, defined as the ratio of tangential momentum to axial momentum fluxes, summed over all the injected fluid streams, is the key controlling parameter for flame shaping. To achieve good practical results, it is imperative that the burner-generated flame is compatible with furnace constraints. This is most critical in water-cooled furnaces such as boilers and especially in packaged boilers. If flame impingement occurs on cold surfaces, carbon monoxide and other by-products of

OPM00 - Basic Principles- Version 2.1.c 4 incomplete combustion will be produced at the point of impingement and severe furnace vibrations occur due to the brutal re-ignition of these by-products.

1.3 CONTROLLING EMISSIONS OF POLLUTANTS: NOX, CO AND

PARTICULATE

Finally, since the mixing rate and its specific distribution determines the temperature and chemical species concentrations within a given furnace, the configuration of the burners in relation with the geometry and flow pattern in the combustion chamber exert a paramount influence on NOX, CO and Particulate formation. The emission of pollutants is intimately linked with furnace configuration and distribution of heat sinks. It is obvious that successful reduction of pollutants in a given furnace requires that the burner configuration be sufficiently adaptable to properly match the furnace flow and temperature fields.

As can be seen, all three burner functions are, to a certain extent, dependent upon furnace configuration. The final measured performance of a burner is in reality the result of its interaction with the furnace. Therefore, a burner cannot be designed independently from the furnace to which it will be installed. Each application must be studied carefully with mathematical models and realistic simulation techniques.

This is NATCOM’s way of insuring that our customers get the best final result for each of their specific burner applications.

2 OPERATING PRINCIPLE AND FEATURES OF THE NATCOM BURNER

The NATCOM burner is an axial flow type based on low to moderate swirling air jet aerodynamics and intensive adjustable fuel staging to control NOx formation.

It uses a unique combination of swirl and central core bluff-body effect to stabilize the flame. The preset ratio of tangential to axial momentum is used to effectively produce the required flame shape for a given furnace geometry. As a standard

OPM00 - Basic Principles- Version 2.1.c 5 feature, each individual gas fuel injector is removable even when the burner is operating.

The air enters the burner through a circular perforated shroud that produces sufficient pressure drop to ensure proper radial air distribution around the burner.

It then converges into the burner axial air tube until it hits the flame stabilizer section. The flame stabilizer is a dual-zone type that uses specially designed variable pitch blades. Near the center, the blade pitch angle is very closed producing a strong and wide back flow of hot burnt gases that sustains combustion of the fresh incoming fuel and air.

When the combustion air flows through the burner, the air stream splits into three portions: one portion is channeled into the inner central core where it will mix with the stabilization fuel, another portion goes through the outer swirling zone where a set of variable pitch blades impart a tangential velocity component, and finally the third portion accelerates and flows purely in the axial direction around the flame stabilizer. The inner central stabilizing core of the burner is built with a variable air inlet that can be externally adjusted when the burner is operating.

The adjustability of NATCOM burner’s allows for easy performance optimization during unit commissioning. As a result of the perfect view of the flame root and the very low air velocity in the core tube, it is an ideal location for the flame scanners and the burner ignitor. Almost any scanner will pick-up the flame even at the lowest loads, allowing NATCOM to guarantee very high, “truly operational” turndown ratios with its burners.

Gaseous fuel is injected using three independent sets of injectors. The first set is located within the inner core tube to insure positive flame stabilization independent of burner load and overall excess air conditions. The second set is used to inject fuel within the swirling flow generated by the variable pitch blades

OPM00 - Basic Principles- Version 2.1.c 6 of the outer swirler. Finally, a third set of gas injectors is used to stage the fuel for

NOx reduction purposes.

As an ULTRA LOW NOx feature, NATCOM has also developed a Furnace

Integrated Recirculation Ejector (FIRE) that allows most boiler applications to generate less than 50 ppm of NOx (0.07 lb/MMBTU) without having to use flue gas recirculation. Its unique aspirator-type design allows the furnace combustion products to premix with the fuel gas injected at the burner outlet. The FIRE system can be easily retrofitted on any boiler membrane wall without any refractory work.

As a unique feature, the NATCOM burner gas injectors can be fully and individually adjusted on-line. The flow rate is adjusted with an individual orifice valve on each injector, injection angle rotation as well as axial translation. This enables the quick on-line optimization of combustion performances without having to shut down the unit to perform burner adjustments. The result is an efficient staged fuel combustion that minimizes NOX and CO formation in a specific furnace configuration, either in single or multiple burner applications.

For oil firing, NATCOM uses a proprietary internal variable-geometry atomizing device that is also adjustable on-line. This feature controls the atomizing steam to oil ratio and, consequently, the penetration of the atomized fuel jets in the combustion air stream. With these unique adjustability features, the combustion aerodynamics can be easily adapted on-line. All performance adjustments can be made upon start-up and even while firing oil with no boiler downtime.

The end result is that NATCOM burners can be optimized for the lowest emissions and highest efficiency performances by fine-tuning the combustion process even while firing at full boiler load.

OPM00 - Basic Principles- Version 2.1.c 7

The refractory throat of the NATCOM burner is straight and cylindrical with no divergence. The use of a diverging throat can be detrimental to the operation of an axial flow burner. For instance, in multiple burner applications a slight variation of the swirler position in a diverging throat will change the flow passage area. It is well known that air flow balance will be altered having a negative impact on overall combustion performance. Also, a diverging throat will guide the air flow outwards producing wider flames and causing severe impingement problems in narrow furnaces. The divergent throat concept was necessary for the old generation of full swirl burners such as the Coen DAZ, the Peabody-H, and the Todd Register. These burners were all designed to produce ball-type flames that were well suited to convert coal-fired cubic shape boilers to oil firing.

Unfortunately, these burner manufacturers have unduly carried the divergent throat concept into their axial flow burner design.

NATCOM’s straight cylindrical throat design is preferable to a diverging throat for several reasons. Firstly. it is easier and less expensive to build. Secondly, it will never overheat as a result of good parallel air flow cooling. And most of all, the swirler positioning prevents air flow imbalance between burners.

OPM00 - Basic Principles- Version 2.1.c 8

L/D = 1.5 L/D = 3

L/D = 5.5

COMBUSTION AERODYNAMICS

Absolute flame stability:

NATCOM’s unique aerated core and radially variable pitch swirl blades provide an absolute flame stability at all loads for excess air from –20% to + 400

High fuel-air mixing efficiency:

The axial, radial and tangential turbulent air flow field generated at the burner outlet is combined with high velocity fuel jets, resulting in an optimized and well defined mixing pattern for maximum local mixture uniformity.

Adaptability:

Burner aerodynamics can be adapted to produce short and wide flames or long and narrow flames. Flame length- to-diameter ratio from 1.5 to 5.5 will fit any boiler type. Fuel gas flow and injection direction can be adjusted on each individual injector to match the air flow perfectly. For fuel-oil injection, Natcom uses a proprietary variable geometry atomizing device with on-line adjustability for optimum oil flame shaping.

OPM00 - Basic Principles- Version 2.1.c 9

ULTRA-LOW EMISSION

Individually adjustable fuel-staged gas injectors allow for optimal use of the available combustion chamber space, resulting in some of the lowest achievable

NOX emissions for a given furnace. NOX can be reduced even further with our unique HYPER-MIX technology that incorporates high momentum steam jets to even out furnace temperatures.

ULTRA LOW NOX HYPER-MIX SYSTEM

Ultra Low NOx Technology less than 10 ppm

It is a well-known fact that NOx are formed in massive quantites where local furnace temperatures exceed 2800 oF. Since most boiler furnaces are designed to operate at average outlet temperatures ranging from 2000 to 2500 oF, NOx formation is the result of poor temperature uniformity within the furnace and more particularly within the flame zone. A perfectly mixed combustion zone results in negligible NOx formation, typically less than 10 ppm.

NAT-COM Solution Temperature Uniformity

Derived from advanced gas turbine combustor technology, Hyper-Mix technology is a revolutionary system that uses the available momentum of high-pressure steam to increase the mixing rates and knock down temperature peaks.

It is designed using state of the art numerical simulation that can optimize results for every specific furnace configuration.

Hyper-Mix technology maximizes temperature uniformity within the furnace. It reduces temperature peaks as well as cold spots, thus reducing both NOx and

CO. The combustion stoichiometry throughout the flame volume is kept fuel lean

OPM00 - Basic Principles- Version 2.1.c 10 to avoid the formation of Prompt NOx. The extremely fast mixing rate of the

NATCOM Hyper-Mix burner also reduces the flame size dramatically. This eliminates the problems of flame impingement and furnace rumbling that have plagued most low NOx burners in the past.

Steam consumption of the Hyper-Mix system is comparable to that of an oil atomizer. It uses less than 1% of the total boiler steaming capacity and the fuel savings due to a flatter excess air curve throughout the entire operating range easily offsets this small cost.

HYPER-MIX A MAJOR STEP FOR THE STEAM GENERATION INDUSTRY

The Hyper-Mix enables boiler operation in the range of 20 to 30 PPM NOx emission without FGR.

Combined with FGR, the NAT-COM Hyper-Mix burner reduces NOx emission down to 5 ppm.

Up to 40:1 turndown.

Standard removable gas injectors for easy maintenance and inspection

Variable geometry oil atomizer for low particulate emission.

On-line adjustment capability for optimum flame-furnace match.

No moving parts during operation.

Easy start-up and maintenance No boiler downtime

The Nat-Com Hyper-Mix burner configuration is designed to be fully adjustable on-line in order to optimize flame shape, NOx, CO, excess air, turndown, etc.

Each of the burner’s gas injectors is equipped with a valve for easy optimization of fuel flow and injection direction. It also allows external injector maintenance, inspection and replacement without the need to shut down.

OPM01 - BURNER AND WINDBOX-Version 2.2.b 1

BURNER AND WINDBOX

OPM01 - BURNER AND WINDBOX-Version 2.2.b 2

1 WARNINGS

2 AIR ZONES AND BURNER FUNCTION

3 BURNER STANDARD OPERATION

4 BURNER MAINTENANCE

5 WINDBOX FUNCTION

6 WINDBOX MAINTENANCE

7 REFERENCE DRAWINGS

OPM-01.V1.2 3

1 WARNINGS

Each part of your NATCOM burner is built with great precision and carefully assembled to provide reliable and safe operation under normal service conditions. However, the equipment was not designed to withstand any of the following:

Brutal shocks or mechanical impacts

Operated without regular maintenance

Modified or altered in any manner

Operated outside its specified range

2 AIR ZONES AND BURNER FUNCTION

To produce, maintain and shape a flame, combustion air is ejected from the burner in three zones with each zone having its own purpose. Flame shape and burner performance are the result of combining the three combustion air zones, fuel injection and the HYPER- MIX system. To obtain consistent air distribution around the burner, a perforated plate is placed on the air inlet common to all three zones.

The stabilizing air zone is located in the center core or inner swirler. The amount of air introduced in this area is relatively small. Air velocity at the outlet of this zone is slow in order to produce a favorable environment for flame stabilization and recirculation of the combustion products.

The swirl air zone supplies approximately one quarter of the combustion air. At the swirler outlet, the air exits at great speed with an induced rotation. This rotating movement has two purposes: first, rotating the air causes a recirculation of combustion products in the stabilizing zone that helps keep the stabilization flame ignited. Secondly, rotating different quantities of air influences flame shape. A larger amount of rotating air produces a wider flame. Furthermore, the rotation tends to stabilize the flame within the burner with what is known as flame tangential continuity.

The axial air zone is located between the swirler and the burner throat. This zone provides most of the combustion air. Air exits with a high axial velocity. The axial air zone is essential to the air-fuel mix because of its high flow and velocity.

A guide pipe is installed in the centre of the burner that allows for easy insertion or removal of the oil gun and connects it to the coupling bloc. The pipe is also used to support the stabilizing gas injector in the burner. A connection is installed at the inlet for cooling air. The air flow within the guide pipe ensures a safe operating temperature and prevents back flow of flue gas from the furnace. For applications only involving gas, the open end of the guide pipe is capped.

3 BURNER STANDARD OPERATION

Refer to the data sheet for the operating pressure and air flow capacity.

OPM01 - BURNER AND WINDBOX-Version 2.2.b

4 BURNER MAINTENANCE

Refer to burner general arrangement.

A regular and meticulous inspection of all components of the burner is essential to ensure safe and reliable operation. An annual inspection must be performed in order to prevent pre-mature wear and / or to discover any unusual problems with the burner.

The airflow through the burner carries dust and tends to build up deposits around the perforated plate. It is essential to make sure that this perforated plate remains clear. Even partial obstruction of the inlet air could drastically alter the burner’s performance.

It is also imperative to check that the burner throat is clear. Any unusual carbon or combustion product deposit could obstruct airflow. Removal and inspection of the swirler (air diffuser) should also be performed regularly. It must be free of any deposits or rust.

Check all bolts and replace them if wear is visible. Note that the ignitor flame and temperature may cause faster than usual wear on such items. When reinstalling the bolts, be sure to replace them in their originally specified locations.

The refractory all around the burner throat must be in good condition, without visible cracks. All the welds must be inspected in order to detect cracks or wear due to firing.

Check all the flanges and gaskets on the front plate.

The airflow element (refer to the burner general arrangement to see if this option is available on the burner) must be cleared of any deposits. Remove the instrumentation from the flowmeter measuring pipe and connect compressed air instead. This will clean the holes around the flowmeter element ring.

5 WINDBOX FUNCTION

The main purpose of the windbox is to direct the combustion air into burner in the most consistent and laminar manner possible.

The windbox is designed to accommodate large quantities of air flow and optimize velocities within different areas of the burner. At the windbox inlet, a perforated plate forces combustion air from the supply ducts into a greater surface, thus flattening out the velocity profile. For the preheated air, the windbox should be insulated so that the external surface temperature does not pose a danger to operating staff. Finally, the windbox offers a flat and rigid surface for mounting the burner, air ducts, fuel trains, instrumentation and/or fans.

6 WINDBOX MAINTENANCE

Refer to windbox general arrangement.

An annual inspection must be done to reveal any wear and / or unusual problems with the windbox. A visual inspection must be done in order to detect any cracks or weld defects.

The junctions between the windbox and all of the ducts must be inspected. All welds between the windbox and the boiler must be checked, as well as a visual inspection of all structural supports.

Windbox bottom drains must be opened regularly in order to empty any water accumulation in the windbox. This inspection is especially critical for units operating in cooler environment and operating with FGR. Not water should be accumulating on the windbox floor.

OPM03 - O-TYPE ATOMIZER- Version 3.2.b 1/9

O-TYPE ATOMIZER

LIGHT OIL GUN MODEL

O41-040, 125, 250 and 400

Version 3.2

OPM03 - O-TYPE ATOMIZER- Version 3.2.b 2/9

1 WARNINGS

2 OIL GUN AND ATOMIZER FUNCTION

3 OIL GUN STANDARD OPERATION

4 OIL GUN AND ATOMIZER MAINTENANCE

4.1 CLEANING OF THE ATOMIZER

4.2 ATOMIZER INSPECTION

4.2.1 INSPECTION FREQUENCY

4.2.2 COPPER GASKETS INSPECTION

4.2.3 NOZZLE AND DISTRIBUTOR INSPECTION

4.2.4 INSPECTION OF OTHER ATOMIZER PARTS

5 STORAGE

6 REFERENCE DRAWINGS

OPM03 - O-TYPE ATOMIZER- Version 3.2.b 3/9

Your NATCOM oil gun is a highly technical piece of equipment built with great precision. It was carefully assembled to provide outstanding fuel oil atomization for several years under normal service condition. However, the oil guns were not designed to withstand any of the following:

Brutal shocks or mechanical impacts

Remain inserted in the burner of a hot boiler without cooling steam o Oil gun temperature should not exceed 1000°F

Stored without proper cleaning

Operate without regular maintenance Modified or altered in any manner

2 OIL GUN AND ATOMIZER FUNCTION

The specific function of the oil atomizer is obviously to atomize the oil and inject it into the burner. The injection is performed in such as manner so as to produce the required flame shape and meet emission levels. Since the atomizer requires regular maintenance, it is also been designed so that it can be easily installed and removed.

The oil gun is comprised of three parts: the male coupling block assembly, the piping and atomizer itself.

The male coupling block assembly allows rapid coupling and de-coupling to the oil piping and atomization steam.

The piping carries the oil and the steam from the male coupling block assembly to the atomizer.

The atomizer channels and controls oil and steam flows in order to properly atomize the oil. Atomization is performed by injecting a high-speed flow of steam through an oil film. The distributor is specially designed to optimize the mixing process between the steam and the oil. The oil gun operates with a constant and positive steam to oil pressure differential. The mix is then ejected through the nozzle in the required shape and at the needed pressure. The NATCOM injection nozzle uses a high precision orifice pattern to control the flame structure and mixing homogeneity within the furnace.

NATCOM manufactures four different sizes of type O41oil guns. They are ranked by their firing capacity, given in MMBTU / hr. The model numbers are given as follows: O41-040, O41-125, O41-250 and O41-400.

OPM03 - O-TYPE ATOMIZER- Version 3.2.b 4/9

The first three digits of the model number refer to the gun type (O41 in this case). The middle three digits refer to the required firing capacity, given in MMBTU / hr. The last two digits of the gun model number describe the nominal gun length in 6” increments. As an example:

Model # O41-125-11 O41 means Gun Type O41

125 means firing capacity of 125 MMBTU / hr 11 means gun length of 6” x 11 =66”

Following is a table showing the range and size of the NATCOM O41 series oil guns.

3 OIL GUN STANDARD OPERATION

The oil gun must be removed when the burner is operating with gas. Furthermore, the coupling block must be closed with a caution plate to avoid serious injury from a steam or oil jet. Oil gun temperatures should not exceed 1000°F in order to maintain mechanical integrity. Refer to coupling block maintenance manual for coupling block servicing and operation.

Before installing the oil gun in the burner, an inspection of all atomizer parts must be performed in order to detect any defects.

The steam and oil gaskets must be inserted in the female block. Whenever the gun has been removed, it is recommended that new gaskets be installed.

Refer to the combustion data sheet for the operating pressure of oil and atomizing steam.

4 OIL GUN AND ATOMIZER MAINTENANCE

NATCOM oil guns are manufactured with high performance and long lasting materials.

Thorough metallurgical studies have been conducted in order to ensure the exceptional life span associated with NATCOM atomizers. Highly technical steels with sophisticated surface hardening treatments are an integral part of the manufacturing process.

However, regular maintenance is required to keep the atomizer performance at its highest level and to ensure a long life for all of the individual components. The atomizer is designed to make routine maintenance both quick and easy.

Model # Maximum Firing Minimum Firing Gun diameter

O41-040 40 MMBTU/HR 5 MMBTU/HR 1.315"

O41-125 125 MMBTU/HR 40 MMBTU/HR 1.660"

O41-250 250 MMBTU/HR 25 MMBTU/HR 2.375"

O41-400 400 MMBTU/HR 50 MMBTU/HR 2.875"

Table 1: Designation of NATCOM O41 - type oil guns

OPM03 - O-TYPE ATOMIZER- Version 3.2.b 5/9

4.1 CLEANING OF THE ATOMIZER

Reference: Atomizer drawing Atomizer tools set drawing

Oil injection nozzles must be cleaned regularly. The frequency of this cleaning will depend on the particular operating conditions of the burner. Initially, daily cleaning of all the injection nozzles should be performed. The frequency of the cleaning can be reduced until the atomizer nozzle is covered with a thin, uniform carbon deposit on its entire surface. If the oil flame produces visible oil droplets or highly opaque smoke, the cleaning frequency must be increased.

For proper cleaning follow the instructions below:

1) Unscrew the atomizer nozzle (item 1 on atomizer drawing) using the nozzle wrench (item 2 on tool set drawing).

2) Withdraw the nozzle and the nozzle gasket (item 1 and 5 on atomizer drawing).

3) Unscrew the oil distributor (item 2 on atomizer drawing) using the locking plate tool (item 1 on tool set drawing). FOR THE O41-040 OIL GUN MODEL (C0DXX

TYPE NOZZLE), DO NOT UNSCREW THE OIL DISTRIBUTOR. IT SHOULD

REMAIN IN PLACE SO SKIP TO STEP 5.

4) Withdraw the distributor, the locking plate and the thrust washer (item 2, 3 and 4 on atomizer drawing).

5) Let all the parts soak in a solvent to eliminate any oil or residue.

6) Use a hand held steel brush to clean the nozzle. A rotary copper brush may also be used for this purpose.

7) Before re-assembly, use tip cleaners to clear the nozzle and distributor holes.

8) Rinse and blow with compressed air.

9) Wipe every part with a dry cloth.

10) Visually inspect every part before re-assembling the atomizer.

11) When re-assembling the atomizer, careful place the pin of the nozzle in the slot of the distributor (Not applicable for C0DXX type nozzle). Apply anti-seize lubricant (Ref LOCTITE Silver Grade anti-seize) on the threads of the nozzle and on the O-rings of the nozzle adaptor.

ALWAYS RE-ASSEMBLE THE NOZZLE AND ITS MATCHING DISTRIBUTOR

WITH THE SAME PART AND SERIAL NUMBER

OPM03 - O-TYPE ATOMIZER- Version 3.2.b 6/9

4.2 ATOMIZER INSPECTION

Ref: Atomizer drawing

The meticulous and regular inspection of the atomizer parts is essential to efficient 7and reliable operation of the oil gun atomizer. All of the individual parts must be thoroughly cleaned before carrying out an inspection.

4.2.1 INSPECTION FREQUENCY

For continuous use, it is recommended to check nozzle, gasket, O-rings and distributor holes at each atomizer cleaning. For the nozzle adapter (item 7 on exploded atomizer drawing), an inspection every four months is normally sufficient. Replacement of the O-rings when the inner surface shows wear is recommended. All the other parts of the atomizer must be inspected annually.

For intermittent use, it is recommended to clean and inspect the parts after each use. The oil gun should never be stored without first being cleaned and inspected. It should also be stored in a safe location.

4.2.2 COPPER GASKET INSPECTION

The copper gasket must be free from cracks, bumps, notches or any other surface defects. Cavities in the gasket surface will appear as a dark spots.

Therefore, if a dark spot extends from one side to the other of the gasket surface, the gasket will leak. Obviously any gasket with the potential for leaking should be replaced immediately.

4.2.3 NOZZLE AND DISTRIBUTOR INSPECTION

Nozzle inspection mainly consists of checking the oil injection orifices. An increase of 0.010 " in the bore is sufficient to alter the oil flow. The nozzle or distributor must be replaced when:

1) One or more oil injection orifices have increased its diameter by 0.010 " or more.

2) Wear has changed the shape of an orifice or any other internal surface.

3) Surface in contact with the nozzle gasket is damaged and leaking.

OPM03 - O-TYPE ATOMIZER- Version 3.2.b 7/9

4.2.4 INSPECTION OF OTHER ATOMISER PARTS

All the other parts of the atomizer must be inspected to detect:

1) The wear of any internal surfaces.

2) The straightness of contacts between the joints

3) The integrity of the screw threads.

4) Any material degradation due to heat exposure.

5) Damages due to accidental impact.

5 STORAGE

Before storing oil guns, make sure that:

1) The gun and its atomizer are well cleaned and emptied of all fluids

2) The steel parts are protected from corrosion.

3) An oil film or grease should be put on the nozzle to increase rust prevention. (Ex:

WD-40 or even #2 oil).

4) Storage environment should be dry (low humidity) and clean.

OPM03 - O-TYPE ATOMIZER- Version 3.2.b 8/9

OPM03 - O-TYPE ATOMIZER- Version 3.2.b 9/9

OPM05 - GAS IGNITOR- Version 2.2.bb 1

EXCALIBUR IGNITOR

Version 2.2.b

OPM05 - GAS IGNITOR- Version 2.2.bb 2

1 WARNINGS

2 IGNITOR FUNCTION

3 IGNITOR STANDARD OPERATION

3.1 IGNITOR PERFORMANCE

3.2 IGNITION SPARK

3.3 IGNITOR POSITION

3.4 HIGH VELOCITY AIR APPLICATION

4 IGNITOR MAINTENANCE

4.1 DISMANTLING THE IGNITOR

4.2 ASSEMBLING THE IGNITOR

4.3 VISUAL INSPECTION

4.4 CENTERING THE IGNITOR HEAD

5 STORAGE

OPM05 - GAS IGNITOR- Version 2.2.b 3

Your NATCOM ignitor is built with high precision manufacturing processes and is carefully assembled to provide reliable ignition. The ignitor will last for several years under normal operating conditions, however, it was not designed to withstand any of the following:

Brutal shocks or mechanical impacts

Soaked in oil, water or any other fluids

Stored without proper cleaning

Operated without regular maintenance

Operated outside its specified range

2 IGNITOR FUNCTION

The purpose of the ignitor is to supply a flame in a zone favorable for burner ignition. The EXCALIBUR ignitor is constructed of two concentric pipes. The center pipe brings the gas to the injection nozzle and serves as conductor for the high-voltage electricity. The electrical spark is produced between the gas injection nozzle and the exterior pipe.

Ceramic isolators and a Teflon plug provide insulation. The exterior pipe channels the air.

The EXCALIBUR ignitor series are engineered and manufactured from materials chosen specifically for their performance and durability. NATCOM manufactures two types of ignitors that meet the requirements of all three NFPA classes. The classes are ranked by different ranges of power output. The basic ignitor, NFPA Class-3, includes a gas pipe, an air pipe and a multiple spark ignition head. NFPA Class-1 and / or Class-2 ignitors have all the features of the Class-3 ignitor and also include a co-axial gas booster allowing them to reach higher power outputs.

Each ignitor can be easily identified by its part number (EXC-C-CL-Y-XX). “CL-Y” represents the ignitor NFPA class, while the last two digits “XX” are for the nominal length of the ignitor itself. However, it should be noted that the following formula, L = (XX*3+1), is used in order to obtain the actual ignitor length. The following is an example of the proper part number identification.

EXC-C-CL-3-26 EXC-C means EXCALIBUR CL-3 means a NFPA Class 3 ignitor 26 means a length of (26x3+1)” =79”

OPM05 - GAS IGNITOR- Version 2.2.bb 4

Table 1 shows the maximum power in MMBTU for each class.

Table 1, Min-Max Power Rating of EXCALIBUR Ignitors

3 IGNITOR STANDARD OPERATION

3.1 IGNITOR PERFORMANCE

3.1.1 PERFORMANCES CURVES

The NATCOM EXCALIBUR ignitors are designed to burn a wide variety of gaseous fuels. The performance curve included in this manual is specific to your ignitor’s operational requirements. The operating air and fuel pressure curves depend on many design criteria such as the length of the ignitor and the type of fuel used. Note that all these curves indicate the operating pressure relative to the furnace pressure.

3.1.2 AIR INLET PRESSURE

NATCOM EXCALIBUR ignitors produce a diffusion type flame. With this type of flame, the combustion air is supplied by the flow surrounding the ignitor.

This concept typically produces longer flames than a premix ignitor. The air flow supplied at the ignitor is only designed to provide an air/fuel mixture ratio high enough to sustain combustion and to prevent hot gas back flow.

The air supply to the ignitor must be dry & clean air. Windbox air pressure is often sufficient to supply air to the ignitor.

Air pressure gauges must be located as close as possible to the ignitor’s air inlet. In order to obtain operating pressure from the performance curve, the pressure at the air inlet must indicate the sum of the operating pressure and the furnace pressure.

Ignitor Min-Max rating (MMBTU/hr)

EXC-C-CL-1-XX 1-10

EXC-C-CL-2-XX 1-10

EXC-C-CL-3-XX 0.1-0.5

OPM05 - GAS IGNITOR- Version 2.2.bb 5

3.1.3 GAS INLET PRESSURE

Gas inlet pressure is taken from the ignitor cap taping. In order to obtain operating pressure readings from the performance curve, the pressure at the gas inlet must indicate the sum of the operating pressure and the furnace pressure.

3.2 IGNITION SPARK

The ignition of the mixture depends mainly on the local stochiometry of the fuel and air mixture at the ignition head. To ensure good sparking for ignition, the high voltage supply must be rated at 6 000 V. Using a higher voltage supply could result in the spark occurring at a location inside the ignitor other than at the ignitor head and is not recommended. Also, the ignitor head must be centered and in good condition (with sharp corners). Inspect the ignitor head on a regular basis.

3.3 IGNITOR POSITION

The NATCOM ignitor must be installed with the spark plug adapter positioned downward, as shown in the fig 4.1. This configuration ensures that water can not accumulate within the spark plug adapter and eventually cause a short circuit. It is permitted to rotate the ignitor 60o CW or CCW. A special flange allows for a quick change of the axial position of the ignitor for easy Start-up and maintenance.

FIG. 4.1 RECOMMENDED POSITION OF THE SPARK PLUG

OPM05 - GAS IGNITOR- Version 2.2.bb 6

3.4 HIGH VELOCITY AIR APPLICATION

The length and stability of the flame are directly related to the combustion air velocity around the ignitor. For greater stability in high velocity air applications (> 30 m/sec), NATCOM ignitors include a support that increases the bluff body effect in front of the ignitor head. The increased bluff body effect ensures flame stability under a wide variety of operating conditions.

4 IGNITOR MAINTENANCE

4.1 DISMANTLING THE IGNITOR

The step-by-step sequence for the complete dismantling of the ignitor is presented below. Refer to drawing IG-6001 or IG-4001 for Class I & II ignitors and to drawing IG-7001 for Class III ignitors.

1- Disconnect the spark plug wire and remove the spark plug from the adapter. Be careful when manipulating the spark plug spring. Inspect for any defects on the spark plug and replace if necessary.

2- Remove the air and gas inlet lines from the ignitor’s body.

3- Remove the gas pressure gauge from the ignitor cap.

4- Remove the flange bolts and pull the ignitor out.

5- Remove the ignitor cap from the ignitor body.

6- Undo the gas plug set screw.

7- To remove the internal components of the ignitor, use a soft hammer and hit gently on the ignitor head until the gas plug is dislodged from the body.

8- Remove the gas plug from the gas pipe. Inspect for cracked or worn gas plug O-rings and replace them if necessary.

9- Pull gently on the gas pipe taking care not to break any isolators.

10- To remove the isolator, take off the isolator retaining rings and slide the isolator to, and off, the end of the pipe. Inspect for any cracked or worn isolators.

Replace any damaged isolators with new ones. Operating with damaged isolators could short the spark plug and result in an inability to ignite the air/gas mixture.

11- Remove ignitor head and inspect for worn corners. Clean the ignitor heads injection holes.

WARNING: BEFORE PERFORMING ANY MAINTENANCE ON

THE IGNITOR, ENSURE THAT HIGH-VOLTAGE WIRE IS

DISCONNECTED

OPM05 - GAS IGNITOR- Version 2.2.bb 7

4.2 ASSEMBLING THE IGNITOR

To reassemble the ignitor, simply follow the disassembly procedure in reverse order.

Important: Lubricate O-rings and O-ring contact surfaces before installing all of the

O-rings in their specified locations.

4.3 VISUAL INSPECTION

A visual inspection of the ignitor should be performed during each boiler shutdown.

1- Inspect ignitor for gas or air leaks.

2- Inspect for ignitor head centering. Refer to section 4.4 if ignitor head is off center.

3- Inspect for any worn parts, especially the ignitor head. Refer to dismantling procedure if ignitor head needs replacement.

4- Inspect for any dirt in the ignitor head injection holes. A visual inspection of the air pipe and booster pipe (for class I & II ignitors) should also be performed. Remove any dirt or residue.

4.4 CENTERING THE IGNITOR HEAD

The centering of the ignitor head must be checked before start-up and / or if the ignitor is not operating properly. Improper centering of the ignitor head may cause malfunctioning of the ignition system. Proper installation of the Isolators should ensure the centering of the heads. The procedure that follows is a step-by-step description of the ignitor head centering process.

1- Follow step 1 to 11 of the complete dismantling procedure.

2- Verify that all isolators are undamaged. Replace them if necessary.

3- Make sure that the gas pipe is straight (by rolling it on a flat surface).

4- Reassemble the ignitor using the reverse order of the dismantling procedure.

5- If the flat face of the ignitor head is not flush with the end of external pipe, remove the gas pipe and adjust the two jam nuts to get the appropriate length.

6- The head must be centered inside the external pipe and each corner must be equidistant to the surface. Note that if the ignitor head is in contact with the external pipe, the ignitor will not spark and a short circuit will occur.

5 STORAGE

Before storing the ignitor, make sure that:

The ignitors components are well cleaned and emptied of all fluids The ignitor is protected from any corrosive environment.

Ignitor must be stored in a dry place.

OPM08 - GAS SUPPORT-Version 2.1.b 1

FUEL GAS INJECTION SYSTEM

OPM08 - GAS SUPPORT-Version 2.1.b 2

1 WARNINGS

2 GAS SUPPORT FUNCTION

3 STANDARD OPERATION

4 GAS SUPPORT MAINTENANCE

OPM08 - GAS SUPPORT-Version 2.1.b 3

Each part of the fuel gas injection system is built with high precision manufacturing processes and is carefully assembled to provide reliable and safe operation. The system will last for several years under normal operating conditions, however it was not designed to withstand any of the following:

Brutal shocks or mechanical impacts

Soaked in oil, water or any other fluids

Stored without proper cleaning

Operated without regular maintenance

Operated outside its specified range

2 GAS SUPPORT FUNCTION

The gas support is made up three different zones:

The stabilizing gas injector supplies gas to the center of the burner in the low velocity area. The gas in introduced as a thin film and it produces the stabilizing flame. This flame stays attached to the burner and continuously ignites the fuel from the main gas injectors.

The stabilizing zone is also the first zone ignited during burner start-up.

The main gas injectors inject gas through multiple orifices. The gas is ignited very quickly and the main stable flame produces about half the total volume of the flame. It will also contribute to the staged gas ignition. The direction of the main gas injectors is used to change the length of the burner flame.

The staged gas injectors are made up of a single orifice. The jet has a large diameter to produce a long flame. The direction of the staged gas injectors is used to change the shape of the flame.

3 FUEL GAS STANDARD OPERATION

Refer to the technical data sheet for the operating pressure.

OPM08 - GAS SUPPORT-Version 2.1.b 4

4 GAS SUPPORT MAINTENANCE

An annual inspection is normally sufficient to reveal any problems with the gas lances.

Check the injection nozzles and clean them if any deposits appear. The cleaning of the injections nozzles is especially important for oil firing systems.

Clear the injection holes of any obstructions.

If the position of the lances has been changed (after a maintenance operation or spare parts replacement) refer to the technical data sheet for the proper installation positions.

The same check must be done for the gas lance valve opening and the stabilization gas nozzle opening.

Inspect all welds of the unions and of the gas ring.

OPM11 – DAMPER v.1.4 1

OPM11 - DAMPER

Version 1.4

OPERATION AND MAINTENANCE MANUAL

OPM11 – DAMPER v.1.4 2

TABLE OF CONTENT

1.0 WARNINGS

2.0 DAMPER FUNCTIONS

3.0 DAMPER TYPES

4.0 DAMPER STANDARD OPERATION

5.0 RECTANGULAR DAMPER BLADE OPENING SYSTEMS

6.0 DAMPER TO ACTUATOR INTERCONNECTING LINKAGE

7.0 DAMPER MAINTENANCE

8.0 PITOT TUBE ADJUSTEMENT (SPECIFIC MODELS ONLY)

9.0 STORAGE

TABLE OF FIGURES

Figure 1: Damper with Pitot tube system Figure 2: Rectangular damper shown with actuator and Pitot tube system Figure 3 : Butterfly damper shown with actuator and limit switches/positioner Figure 4: Butterfly damper with linkage system and two position switches Figure 5: Rectangular damper with linkage system and three position switches Figure 6: Linkage connected to the arm of the actuator Figure 7: Mechanical stopper adjustment Figure 8: Position switches adjustment Figure 9: Sequential damper Figure 10: Adjustable linkage, as typically set at the factory Figure 11: Sketch of the linkage Figure 12: Bearings to be greased Figure 13: Packing replacement Figure 14: Pitot tube maintenance Figure 15: The Pitot tube systems Figure 16: Low combustion air signal adjustment Figure 17 : Effects of moving the low combustion air Pitot tube system

OPM11 – DAMPER v.1.4 3

1.0 WARNINGS

Even though this equipment was designed to be extremely secure, reading this manual is mandatory to minimize the risk of injuries.

Each part of the damper is built with great precision and is carefully assembled to provide a reliable and safe operation under normal service conditions. However this equipment is not designed to withstand any type of abuse such as:

Operation without regular maintenance Modification or alteration in any manner Operation outside its specified range

OPM11 – DAMPER v.1.4 4

2.0 DAMPER FUNCTIONS

The purpose of the damper is to control the air flow and/or FGR flow to the burner. The damper is made up of blade(s), shaft(s), a linkage system and a flanged rectangular or round casing.

For applications with flue gas recirculation (FGR), the air damper may also be used to read the minimum air flow and purge air flow signals before the mix of flue gas and fresh air. In this case, two differential pressure switches are mounted on the damper. They are connected to a Pitot tube system installed between the blades (ref. Figure 1).

Figure 1: Damper with Pitot tube system

Section 4 of this manual covers the standard operation of the damper and air flow switches, section 7 describes the maintenance procedure for reliable operation.

Differential pressure switches

Pitot tube systems

Actuator

Actuator mounting bracket

OPM11 – DAMPER v.1.4 5

3.0 DAMPER TYPES

Dampers have different characteristics depending on their type. Below are four typical types of NATCOM dampers (many other configurations are possible):

Figure 2: Rectangular damper shown with actuator and Pitot tube system

Figure 3 : Butterfly damper shown with actuator and limit switches/positioner

Spring return housing

Actuator

Positioner and/or limit switches

OPM11 – DAMPER v.1.4 6

Figure 4: Butterfly damper with linkage system and two position switches

Figure 5: Rectangular damper with linkage system and three position switches

OPM11 – DAMPER v.1.4 7

4.0 DAMPER STANDARD OPERATION

IMPORTANT: During commissioning, a check of the following points must be done:

- Verify that the linkage is connected and firmly tightened to the arm of the damper with the provided shoulder bolt (ref. Figure 6). It is very important that there is no loose play between these two elements. If the damper is directly driven by an actuator, make sure the actuator coupling is present and tightly connects the actuator to the shaft.

Figure 6: Linkage connected to the arm of the actuator

Linkage arm

OPM11 – DAMPER v.1.4 8

- Verify that the mechanical stopper is correctly adjusted to keep a gap at the minimum position of the blades (ref. Figure 7). This ensures a minimum air flow through the damper. An exception is taken when a tight shut-off damper is required. In this special case, minimal leakage is tolerated. In some cases, there is a mechanical stopper for the maximum position also. Stopper location may vary depending on your actual damper configuration. It may also need to be adjusted to ensure the linkage will not over travel.

Figure 7: Mechanical stopper adjustment

- If applicable, verify that the pressure switches are correctly installed and piped to the Pitot tube elements.

- If applicable, verify that the Pitot tube support is correctly adjusted and tightened on the damper (refer to the maintenance section for the adjustment).

Mechanical stopper

OPM11 – DAMPER v.1.4 9

- Verify that the position switches are correctly adjusted (contact must be made at both the minimum and purge positions) (ref. Figure 8). If position switches are integrated to the actuator positioner, refer to Volume II of maintenance manuals for actuator positioner adjustment instructions.

IMPORTANT: Upon final tuning of the above, all linkage arms must be positively locked in place with the supplied spring pins (ref. Figure 8).

Depending on the configuration, the linkage may be factory locked.

Figure 8: Position switches adjustment

Position switches

Spring pin

OPM11 – DAMPER v.1.4 10

5.0 RECTANGULAR DAMPER BLADE OPENING SYSTEMS

NATCOM dampers use three different opening systems: opposed blades, parallel blades and sequential blades.

1. Opposed blades damper: each pair of blades open with the same angle in an alternate direction.

2. Parallel damper: each blade opens with the same angle and in the same direction.

3. Sequential opening damper: the linkage system is optimized to allow each blade to open with a different angle and give a better control of the flow. As typically set at the factory (ref. Figure 9, top picture), when the first blade is completely open (90°), the other blades are not. It is possible with the sequential opening configuration to rearrange the linkages such that some, or all of the blades open as they would with a parallel damper (ref. Figure 9, bottom picture).

Figure 9: Sequential damper

OPM11 – DAMPER v.1.4 11

6.0 DAMPER TO ACTUATOR INTERCONNECTING LINKAGE

The linkage connecting the actuator to the damper can be adjusted as required for an optimal control of the damper over of its operating range. The possible options to set the damper linkages are summarized in table 1. The following figure (ref. Figure 10) shows the adjustable linkage at its initial (closed) position.

Figure 10: Adjustable linkage, as typically set at the factory

6.1 Setting the damper minimum position

There are two possible ways to set the damper at its minimum position:

6.1.1 Rotating the actuator up to the desired initial position. The resulting maximum damper opening versus initial position and linkage setup can be found in table 1.

6.1.2 Changing the linkage setting while maintaining the actuator at its initial position. Depending on the desired minimum and maximum damper opening, adjust the driver and driven arm length (L1, L2) along with the interconnecting rod length (LROD) based on the options shown in table

1. Other options than the ones presented in table 1 are possible.

These options can result in over travel and possible damage to the damper and should be avoided.

In any case, the stopper must be adjusted as discussed in section 4. Final interconnecting linkage configuration shall be recorded in the commissioning/start-up documentation and communicated to NATCOM.

Figure 11: Sketch of the linkage

OPM11 – DAMPER v.1.4 12

Table 1: Possible linkage adjustment options

Actuator starting angle (θ1)

Actuator arm L1 (in)

Damper arm L2 (in)

LROD*

Damper blade minimum opening (°)

Damper blade maximum opening (°)

0° 4 4 min 1,7 67,2 max 15,8 81,6

4° 4 4 min 2,6 67,2 max 16,8 81,6

8° 4 4 min 3,9 67,2 max 17,9 81,6

0° 4 5 min 8,4 62,4 max 19,1 73,7

4° 4 5 min 9,3 62,4 max 20 73,7

8° 4 5 min 10,4 62,4 max 21,1 73,7

0° 4 6 min 12 58,6 max 20,6 67,9

4° 4 6 min 12,9 58,6 max 21,5 67,9

8° 4 6 min 13,9 58,6 max 22,6 67,9

0° ** 5 ** 4 ** min 0 80,4 max 0 80,4

4° 5 4 min 0 79,3 max 1,2 80,4

8° 5 4 min 0 78 max 2,6 80,4

0° 5 5 min 0 66,5 max 7,4 73,6

4° 5 5 min 0 65,5 max 8,5 73,6

8° 5 5 min 0 64,4 max 9,8 73,6

0° 5 6 min 2,1 59,4 max 11,3 68,5

4° 5 6 min 3,2 59,4 max 12,4 68,5

8° 5 6 min 4,5 59,4 max 13,7 68,5

0° 6 6 min 0 67,3 max 1,3 68,5

4° 6 6 min 0 66,2 max 2,5 68,5

8° 6 6 min 0 64,9 max 4 68,5

*Based on a maximum rod length adjustment of 0.89”, larger adjustment may be achieved depending on actual linkage rod end size **Typical factory setting

OPM11 – DAMPER v.1.4 13

7.0 DAMPER MAINTENANCE

An annual maintenance and inspection of the damper must be done in order to detect any defects and prolong the life of the damper.

- Check the condition of the bearings and jack-shaft/actuator mechanism.

- Lubricate the bearings with a waterproof grease that can handle a temperature range of -22°F to 230°F (SKF LGMT 2 or equivalent, unless otherwise specified) (ref. Figure 12) for low temperature applications. For high temperature application, on flues or breeching, use Loctite Viper Lube (NLGI2) or equivalent. Mechanically disconnect the damper from the actuator and manually try to open and close the damper to estimate bearing friction. Bearings used are sealed type ball bearings. Minimal amount of grease shall be required.

- In the case of a round damper or outboard bearing arrangement dampers, sealing packing (Expanded exfoliated graphite, ROBCO 1200 Thermograph or equivalent) must be inspected and replaced if packing is no longer providing an adequate seal around the shaft (ref.

Figure 13).

- Inspect mechanical stop(s) for mechanical integrity, switches, mounting brackets and linkages for any loose play.

- Verify that all blades are mechanically linked and positively secured on their respective mounting shafts.

- Verify that all the locking spring pins are still in place and secure.

- The actuator specific maintenance procedure can be found in Volume

II of the maintenance manual.

OPM11 – DAMPER v.1.4 14

Figure 12: Bearings to be greased

Figure 13: Packing replacement

- During operation, some dust could obstruct…