Delta Valves Tech Tips

TechTIP #1 Stroking The Valve After Long Term Storage

This procedure is for customers storing their DeltaGuard bottom unheading device(s) for periods longer than six months prior to being installed.

In order to prevent corrosion in the actuator the valve must be stroked at least every six months.

A list of items needed to operate and clean the GV815/820 is provided below:

Equipment

1. Portable HPU (3-phase 460 volt) 2. Hydraulic hoses for HPU-to-cylinder connections (not provided with HPU)3. Compression ring rental provided by DeltaValve4. Small crane to lift compression ring into place

Labor

1. OneDeltaValvefieldsupervisor2. Two maintenance personnel to run studs/nuts for the compression ring

Parts

1. 28 body-to-spool studs2. 28 body-to-spool nuts

Consumables

1. Anti-seize thread2. Rags3. Rustcleaner/inhibitorspray(Noflashorsimilar)4. Half-quart motor oil per valve5. Tapping oil6. Hydraulic oil 65 gallons per cylinder plus extra for the HPU tank and lines.7. DryFloortypeproducttocleanupanyspilledfluids.

Tools

1. Pneumatic impact gun2. Socket for body-to-spool nuts3. Tap for body-to-spool stud holes4. Multiplefivegallonbucketstocatchanyexcess/spilledhydraulicoil

For more information, contact the DeltaValve Customer Service Department. 801.984.1000 Toll free 1.888.DeltaValve [email protected]

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Storage Maintenance Process

1. Complete job safety analysis2. Clean valve 3. Insert studs in every other hole on body-to-spool connection4. Install compression ring and torque in star pattern, followed by chaser pass5. Hook up HPU to cylinder6. Lubricate gate with motor oil7. Stroke valve to open position8. Stroke valve to closed position9. Remove compression ring 10. Apply fresh rust inhibitor to compression ring

For more information or to schedule service, please contact the DeltaValve Maintenance and Service department at 801-244-1528.

TechTIP #1 (Continued)


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TechTIP #2 Transition Spool Connection: Flanged vs. Weld-inThe Transition Spool can be connected to coke-drums utilizing either a flanged (bolt-on) or weld-in connection. Installation and maintenance procedures vary for each connection. Since installation, each connection method historically has had no leaks requiring maintenance thus DeltaValve does not recommend one installation method over the other.

Installation Considerations:A possibility of flange leaks around the flange.1. A possibility of localized drum stress from the side feed entry causing cracks in the weld and 2. forcing downtime for repair. Again, experience has proven with proper design and installation, both connection types provide satisfactory performance levels.

Space or constricting dimensions on the cutting deck. 3.

Pros and Cons to Flanged Spool Drum ConnectionPro: If needed, replacement is confined to a relatively inexpensive, disposable spool. The exchange of a spool is a minor maintenance exercise and can be done between cycles. Con: Although there have been no leaks historically, the fear of leakage is still prominent in all flange connections. Life expectancy of the spool and gaskets have yet to be determined.

Pros and Cons to Weld-in Connection side feed entry Pro: The weld-in design is a permanent transition to the DeltaGuard. Con: If needed, there is no easy way to remove and replace the damaged transitioning spool.


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Installation MethodsSalt Lake City, UT 2 Drums Operating since September 20, 2001.

Original spool design with upturned connection. Non balanced valve moments on flange connection (spring-cans are not set to balance weight of valve about the flange centerline. For added clarification of spring-can operation, see the IOM DeltaLift).Gaskets require maintenance quarterly or semi annually.

Pascagoula, MI 6 Drums Operating since February 2003.

Original spool design with upturned connection. Non balanced valve moments on flange connection (spring-cans are not set to balance weight of valve about the flange centerline. For added clarification of spring-can operation, see the IOM DeltaLift).Gaskets do not require maintenance since Chevron have installed flange clamps to eliminate quarterly gasket maintenance.

El Segundo, CA 6 Drums Operating for approximately 21 months.

Leakless spool design Non balanced valve moments on flange connections (spring-cans are not set to balance weight of valve about the flange centerline. For added clarification of spring-can operation, see the IOM DeltaLift).Performing within specified standards.

Shell Willmington Ca. 4 Drums Performing since February 2004.

Bolt DeltaGuards direct to new drum bottom flanges. New cone sections contains inlet feed lines and mating flanges for the DeltaGuard.Balanced valve moments on flange connections (spring-cans are not set to balance weight of valve about the flange centerline. For added clarification of spring-can operation, see the IOM DeltaLift).No weeps or leaks of any kind or size.

Texas City, TX 2 Drums Operating since April 2004DeltaGuard is bolted directly to a new drum bottom flange with horizontal feed-line. Balanced valve moments on flange connections (spring-cans are not set to balance weight of valve about the flange centerline. For added clarification of spring-can operation, see the IOM DeltaLift).No weeps or leaks of any kind or size.


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TechTIP #3Purge Steam Requirements for the DeltaGuard

Appropriate usage of purge steam while operating the DeltaGuard will decrease wear and tear, and maintenance on valve internal components.

Steam Consumption Steam purge requirements vary from model to model during the stroke. Highest purge steam is with the GV810, designed for on/off service, lower for the GV815, designed for drainable service, and lowest for the GV820, designed for throttling service.

Control System DesignThe steam differential control system should be designed to support purge steam pressure in the unheading device at a constant 20 PSI above drum pressure. Differential pressure is required to keep the process out of the unheading device. Steam quantity requirements will remain as shown in Table 1, unless an unheading device has malfunctioned or has been severely damaged.

Unheading Device Normal SteamLb/hrFeed Switch-In Steam

Lb/hr

60 Bottom 0 - 800 0 - 6000

36 Top 0 - 200 0 - 720

30 Top 0 - 150 0 - 600

Table 1 Steam consumption rates for the 20 psi control range.

At the beginning of the warm up cycle, or the point of switch-in, purge steam should be at or near the normal rate. After switch-in the steam flow rate rises to the switch-in rate and then back to the normal rate for the remainder of the coking cycle. This spike typically begins and ends within two hours. As the valve is stroking, an opening is present which allows purge steam to escape unrestricted. The steam system pressure control valve is usually open during this period, and is not expected to maintain pressure.

Emergency Steam ConsumptionEmergency is a term used to describe a worst-case scenario (i.e. severe damage has occurred to the seat assemblies and the seal has been compromised). Emergency steam consumption is a design allowance for rare or extreme events that could occur. When the steam control valve is open, it

Formoreinformation,contacttheDeltaValveCustomerServiceDepartment. 0302.1207801.984.1000Tollfree1.888.DeltaValvecustomercare@deltavalve.com

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should be able to supply steam at, or above, the emergency rate shown in Table 2. The control valve does not need to control pressure in an emergency condition.

Unheading Device Emergency SteamLb/hr

60 Bottom 7500

36 Top 1800

30 Top 1500 Table 2 Minimum Emergency Steam Consumption.

Steam ConsumptionProcess steam rates for coking and de-coking operations are listed in Table 3, and provide a base in calculating the total purge steam required. Rates are for a single unheading device. Note: The minimum steam rate is the value at the lowest end of the normal steam rate range.

Operation Bottom Unheading Device Purge Steam Lb/Hr

36 Top Unheading Device

Purge Steam Lb/hr

30 Top Unheading Device

Purge Steam Lb/hr

Close Un-heading Device

Maximum 6000(2 to 4 minutes)

Control Valve Closed(1 minute - 3 minutes)


Preheat Coke Drum 0 - 800 0 - 200 0 - 150

Switch-in Feed 0 - 6000(45 min. to 2 hrs)0 - 720

(45 min. to 2 hrs)0 - 600

(45 min. to 2 hrs)

Coking (from 2 hours after switch-in to end of cycle)

100-800 0 - 200 0 - 150

Quenching 100-800 0 - 200 0 - 150

Draining 100-800 0 - 200 0 - 150

Open Un-heading Device

Maximum 6000(2 to 4 minutes)



Coke Cutting 0 - 800 None None

Table 3 Steam Consumption Ranges For Various Operations.



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GV810 Steam ConsumptionThe GV810 DeltaGuard is a base model designed for on/off service only. On/off service means that prior to unheading the drum, the quench water is completely drained from the drum. Under such conditions it is anticipated that only small quantities of coke particulate, chunks and/or water will drop from the drum while opening the valve, and is not necessary to use continuous positive pressure. Instead, low pressure high volume steam is used to sweep the internal gate shroud clean and return any deposited solids back through the valve port and into the pit. Upon initial opening no restriction is placed on the egress of steam from the valve body and bonnets through the valve port since the body and bonnets are resealed and pressurized by the dual metal valve seats at each end of the stroke. The high steam flow will occur only while the gate is stroking.

GV815 Steam ConsumptionThe GV815 is designed for drainable service. This means operators are able to drain a full or partial drum of quench water and/or coke fines and solids entirely through the DeltaGuard. The drainable valve is designed to be stroked from the closed position to the fully open position without stopping, or throttling to slow the gate. The GV815 is the same as the GV810 with the addition of a power shroud. The hydraulic actuators move the machined end cap to seal off the end of the power shroud while the shroud is closed and the lower bonnet is pressurized with steam. Solids and water can not pass from the valve port through the interior of the shroud cavity and into the bonnet of the valve. The machined end cap seals tightly against the end of the power shroud. This seal significantly reduces steam egress from the positively pressurized lower bonnet by the power shroud while it is closed. Steam in a pressurized upper bonnet is able to escape through a passage way at either side of the gate between the body inner diameter and the gate outer diameter. The total steam passage area at the sides of the gate is smaller than the steam purge inlet lines of the bonnet so the upper bonnet purge pressures can be maintained at or above drum pressure if the main purge steam control valve is wide open. This high volume of steam use will only last for the duration of the stroke.

Although the GV815 is designed to maintain a positively pressurized and sealed bonnet cavity while the valve is stroking, steam consumption will remain high during this brief period. This is due to the absence of gate side seals.

GV820 Steam ConsumptionThe GV820 embodies the same power shroud of the GV815 but adds gate side seals. The gate side seals block off steam egress between the body inner diameter and the gate sides while the valve gate is stroking. The effect of this feature is to enable the bonnets of the GV820 to remain positively pressurized for extended periods of time, as may be required while throttling. During this time steam consumption will be significantly reduced to a volume that is easily sustainable.



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Purge Steam Allocation:

Un-heading Device Purge Steam Lb/hr Unheading Device Condition

Drum 1 Bottom 7500 Emergency

Drum 1 36 Top 200 Normal

Drum 2 Bottom 6000 Switch-in Feed


Total Steam 13900 Using 36 Top Unheading Devices

Drum 1 Bottom 7500 Emergency


Drum 2 Bottom 6000 Switch-in Feed


Total Steam 13800 Using 30 Top Unheading Devices

Table 4 Steam Header Sizing Values.

Steam Trap SpecificationTo size the steam traps, calculate the amount of condensate by using the normal condition steam rates and assume all of the steam will return to condensate. Apply the safety factors recommended by the traps manufacturer. Note: The condensate may be contaminated with some solids.

There will be variances in normal steam consumption from refinery to refinery. To assure steam consumption levels shown in this document are achieved, it may be necessary to set the normal differential pressure between the valve body and the drum to a value other than 20 PSI. Acceptable delta pressures for the normal operating cases are permissible anywhere from 1020 PSI.

Actual steam values will most likely be the lower values of the ranges shown in this document.



TechTIP #4 Pressurizing the Gate Shroud for the GV815/GV820To avoid a possible pressure overage on the internal gate shroud while when the coke drum is full of water modify the control specifications to reduce the body steam purge pressure to 20 PSI prior to opening the DeltaGuard.

Pressure GuidelinesDeltaValve specifications require body purge steam pressure to be maintained at a constant 20 PSI above drum pressure. At the initial opening of a full coke drum the pressure tap will measure the drum water head normally 22-44 PSI. In a properly configured system the pressure controller will adjust the body steam pressure to 20 PSI above the drum water head resulting in a body steam pressure of 42-64 PSI.

Since the internal gate shroud is designed to optimally operate at pressures of 25 PSI the body steam pressure will need to be reduced to 20 PSI prior to unheading.

Measuring Drum PressureRecording measurements from the proper location on the drum will ensure the drum water head is correctly included when calculating the required amount of body steam pressure.

Procedure:

Measure the drum vapor pressure at the top of the drum. Measuring drum pressure at the feed-line Estimate the water head pressure then add to the drum vapor pressure.


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TechTIP #5 DeltaGuard Warm-up Procedure

The purpose of this procedure is to ensure that all bonnet welds achieve the ASME code suggested impact values prior to full pressurization of the bonnets.

Warm up procedure for the DeltaGuard GV815/GV820 for temperatures starting below 80F.

Procedure:

Throttle the valve to a partially opened position a minimum of 6.625 inches. This will allow steam to escape the body and bonnets without causing pressurization. An alternative to throttling the valve is to open the steam trap bypass valves. Note: Only certain models of the DeltaGuard have steam trap bypass valves as an added option. Introduce steam into the body of the DeltaGuard until temperatures of the body and bonnets reach at least 80F.Once the DeltaGuard reaches its goal temperature, the gate can be closed and the valve fully pressurized.


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TechTIP #6 Developing a Maintenance Plan for DeltaGuard Unheading Systems (GV810, GV815, GV820)

DeltaValve is able to assist in developing a maintenance plan to help customers achieve maximum value from their investment in a DeltaGuard unheading system. The first step to developing this plan is performing a site audit conducted by qualified DeltaValve Maintenance and Service department representatives. The purpose of this audit is to give foresightwith a defined set of actionsthat can be scheduled and performed over the years leading to the next scheduled turnaround and beyond.

It is recommended that a pre-audit and inspection meeting be held between key plant personnel and DeltaValve Maintenance and Service representatives the day leading into the audit. The purpose of the pre-audit meeting is to lay out goals and set action items, plus answer any questions pertaining to the audit.

Systems to be examined during the audit include: hydraulic skid and components, hydraulic line runs, valve support systems, cooling box, water supply, steam supply and trends, gasket condition, condensate outlet(s), proximity switches, valve performance and condition, and safety.

A published report detailing all findings and recommendations, including basic safety procedures for the DeltaGuard, will be given to key plant personnel following the audit. A brief post audit meeting will be held to review or highlight more critical findings in the report. Pending customer approval, DeltaValve will publish their findings and recommendations in the customers DeltaValve Customer Care portal (http://customercare.deltavalve.com.) where other invited plant personnel can review these findings as needed. Consult the plant manager or DeltaValve Customer Service for username and password. A basic five year maintenance plan may include the following:

Year 1Activities:

DeltaValve site audit Adjust packing

Parts: (1) Cooling box cover gasket

Year 2Activities:

DeltaValve site audit Adjust packing Inspect internal cavities via inspection covers Flush cooling box, if needed

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Parts: (1) Cooling box cover gasket (2) Upper bonnet clevis access cover gaskets (2) Lower bonnet inspection port cover gaskets

Year 3Activities:

DeltaValve site audit Adjust packing

Parts: (1) Cooling box cover gasket

Year 4Activities:

DeltaValve site audit Adjust packing Inspect internal cavities via inspection covers

Parts: (1) Cooling box cover gasket (2) Upper bonnet clevis access cover gaskets (2) Lower bonnet inspection port cover gaskets

Year 5Activities:

DeltaValve site audit Inspect gate and seats Replace body-to-drum gasket Replace packing Flush cooling box

Parts: (2) Cooling box cover gaskets (1) Body-to-drum gasket (1) Body-to-chute gasket (1) Actuator rod packing kit (1) Lockout shaft packing kit (2) Power Shroud packing kits (GV815 and GV 820 only)

NOTE: * Steam condensate strainers and traps should be purged monthly.


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* DeltaValve recommends inspecting the gate and seats of one valve six months prior to a major turnaround. * Internal component replacement schedule is dependant on the specific operating conditions and preventative

maintenace action at each plant. Conducting regualr site audits with DelatValve will help determine at which major turnaround valve refurbishmnet should take place as well as the extent of the rebuild.

Additional information regarding spare parts ordering on all unheading systems is available from the DeltaValve Customer Service Portal. Go to http://customercare.deltavalve.com to register.

DeltaValve is committed to providing superior customer service on all our products. For more information or to schedule service, contact the DeltaValve Maintenance and Service Department at 1-888-deltavalve.



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TechTIP #7 Emergency Stroke Procedure for the DeltaGuard GV830 30 Top Unheading Device

The DeltaGuard top unheading device is not equipped with an auxiliary actuator option. In the event of a hydraulic seal failure on the main actuator, follow the procedure below to stroke the DeltaGuard from the closed to the open position. It is recommended that the customer contact DeltaValve for assistance in performing this procedure. Prior to returning the DeltaGuard to service, the main actuator failure must be resolved. Contact DeltaValve field services for repair and parts assistance.

Symptoms of main actuator seal failure include deteriorating stroke speed and hydraulic fluid in the cooling box. When inspecting the cooling box for hydraulic fluid, make sure the main actuator is de-energized prior to removing the cooling box flanges.

Stroking Procedure

1. Cool the drum to unheading temperature. Verify that the permissives have been met to unhead the drum. Open the overhead vent line on the drum prior to working on the DeltaGuard top unheading device.

2. Turn off and lock out the steam to the DeltaGuard. Vent the body to atmosphere and allow the body to cool.

3. Turn off water to the cooling box. Drain the cooling box and disconnect cooling box piping.

4. Lockout and remove hydraulic lines from the main actuator.

5. Disconnect all actuator and lockout tower proximity switch connections.

6. Loosen the retainer flange nuts to remove the clamping load on the gate. Incrementally loosening each nut in a star pattern will prevent binding of the retainer flange fasteners.

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7. Support the weight of the main actuator, lockout tower, and top flange while removing the 1 inch-8UN bolting at the stuffing box end cover to body connection. The lockout tower, main actuator, and stuffing box end cover assembly weighs around 1600 lbs.

8. Use pry bars to create a gap between the stuffing box end cover and the body big enough to place a strap through the opening and around the stuffing box end cover. Center the strap on the stuffing box end cover to avoid binding the gate as the gate is repositioned to the open position.

9. Use a chain-fall secured in the same horizontal plane as the gate and connected to the strap to pull the gate into the open position. Position the orifice in the gate so that it is concentric with the seat orifices. Approximately 65 inches of clearance beyond the end of the Main Actuator will be required to reposition the gate.

10. Tighten the nuts on the retainer flange to restore the clamping load on the gate. Torque the retainer flange nuts to in three increments using a star pattern to the 490 ft.-lb.

11. The main hydraulic cylinder will need to be repaired or replace prior to returning the DeltaGuard to regular service. Contact DeltaValve field service for repair and parts assistance.


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TechTIP #8 Auxiliary Actuator Install Procedure GV810/815/820 DeltaGuard Bottom Unheading Device

The auxiliary actuator is used to open and close the DeltaGuard unheading device in the event of a main actuator failure. The auxiliary actuator bolts to the end of the lockout tower and is pinned to the end of the lockout stem.

The auxiliary actuator requires approximately 95 inches of clearance beyond the end of the lockout tower for installation and removal (see figure 1). Reference the hydraulic system documentation for instructions on connecting hydraulic lines and bleeding.

Installation

1. Remove the end cover on the back of the lockout tower (see figure 2).

2. Remove the screw securing the cylinder hub pin.

3. Withdraw the cylinder hub pin.

4. Remove the coupler support.

5. Prepare the auxiliary cylinder by threading the cylinder hub onto the cylinder shaft (see figures 2 and 3). The cylinder hub should engage the cylinder shaft by 4-1/2 inches to accommodate maximum stroke.

6. Connect hydraulic lines to the auxiliary actuator and bleed the system.

7. Lift the auxiliary actuator and align the center line of the auxiliary actuator with the center line of the coupler.

8. Extend the auxiliary actuator until the cylinder hub contacts the coupler plus approximately 11 inches.

9. Insert the cylinder hub into the coupler.

10. Insert the cylinder hub pin and secure with screw (see figures 2 and 3).

11. Align the auxiliary actuator mounting holes with the lockout tower end plate and retract the auxiliary actuator slowly until the auxiliary actuator contacts the lockout tower's end flange.

12. Bolt the auxiliary actuator to the lockout tower using 2 inch-8UN studs and nuts. Apply anti-seize to stud threads and torque to 1700 ft-lbs. The auxiliary cylinder can now be used to stroke the DeltaGuard.


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Removal

1. Support the auxiliary actuator in preparation for removal.

2. Remove the 2 inch-8UN studs connecting the auxiliary cylinder to the lockout tower.

3. Extend the auxiliary cylinder approximately one inch to remove any bind on the cylinder hub pin.

4. Remove the screw securing the cylinder hub pin and withdraw the cylinder hub pin.

5. Disengage the cylinder hub from the coupler.

6. Fully retract the auxiliary cylinder and remove from the end of the lockout tower.

7. Insert the coupler support into the coupler.

8. Insert the cylinder hub pin and secure with screw.

9. Install the end cover on the back of the lockout tower.

10. Store the cylinder hub with the auxiliary cylinder for future use.

Figure 1: Auxiliary Cylinder Install Clearance

Figure 2: Lockout Tower Assembly

Figure 3: Auxiliary Actuator to Lockout Tower Connection


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30_in_Top_Unheading_Spares-336_in_Top_Unheading_Spares-360_in_Bottom_Unheading_Spares-3Delta valve tech tipTechTIP1_Stroking_the_Valve_in_StorageTechTIP2_Transition_Spool_Connection-Flange_vsWeld-InStyleTechTIP3_Purge_Steam_Requirements_for_the_DeltaGuardTechTIP4_Pressuring_the_Gate_Shroud_for_the_GV815-8120TechTIP5_DeltaGuard_Warm-up_ProcedureTechTIP6_Developing_a_Maintenance_Plan_for_DeltaGuard_Unheading_SystemsTechTIP7_Emergency_Stroking_Proceedure_for_the%20DeltaGuard_Top_Unheading_DeviceTechTIP8_Auxillary_Actuator_Installation_Procedure_for_the_DeltaGuard

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