INSTRUCTION MANUAL 7 1/16 10K SLAB GATE BODY
INTRODUCTION The NF-700 type gate valves provided by Neeco Industries are full-bore through conduit non-rising stem manually (w/ball screw) operated valves. The NF-700 model has a slab gate with floating seats thus offering a true metal-to-metal seal that is very reliable. The ball-screw mechanism on the valve provides for low operating torque and is widely accepted due to its ease of operation. The NF-700 valve has a proven and tested design from years of use in the field. Neeco Industries has prepared this Instruction Manual to assist in the assembly, installation, operation and maintenance of the product. If you need more information or assistance, you should contact: Neeco Industries, Inc. 13320 Emmett Road Houston, Texas 77041 Tel: 713-937-6366 Toll Free: 866-495-1419 Fax: 713-937-6380
SCHEMATIC DIAGRAM
BILL OF MATERIAL Valve Model NF - 700, 7 1/16 10K, FE,/Ball Screw EE Trim Item # Description Qty Mat l 1 Handwheel 34 1 Ductile Iron 2 Bonnet Cap 1 AISI 4130 3 1/8 Injection Fitting 2 Buy-out 4 O Ring 178 (internal) X 3.5 1 Buy-out 5 Needle Bearing 2 Buy-out 6 Upper Stem Protector 1 WCB 7 Indicating Adapter 1 AISI 316 SS 8 Bearing Nut 1 ASTM B 62 9 O Ring 73 (internal) X 3.5 1 Nitrile Rubber 10 Bearing Housing 1 AISI 1020 11 Packing Gland 1 AISI 4130 11a Stem Packing 2 PTFE + Viton 12 Studs (1 7/8-8UNC) 24 AISI 4140 13 Heavy Hex Nut (2 15/16 ) 24 AISI 1045 14 Upper Bonnet 1 AISI 4130 15 Upper Stem/Ball Screw 1 Assy Parts 316 SS 16 Bonnet Gasket 2 316 SS 17 Gate 1 AISI 4130 +Colmonoy# 5 18 Junk Ring 1 Nitrile Rubber 19 Seat Seal Ring 4 PTFE+Graphite 20 Retainer Plate 2 AISI 1020 21 Valve Body 1 AISI 4130 22 Name Plate 1 AL 23 Name Plate Screws 4 Buy-out Part 24 1/2 NPT Grease Fitting Valve 2 Buy-out Part 25 Gate Guide 2 CS 26 Lower Stem 1 AISI 410 SS 27 Lower Stem Protector 1 WCB 28 Lower Bonnet 1 AISI 4130 29 Seat 2 410 SS + Colmonoy # 5
TEMPERATURE RATING NOTE: For special applications involving different sizes or pressure ratings, temperatures, materials, etc., please contact Neeco Industries customer service.
DESCRIPTION AND FEATURES The NF-700 valve is a full-bore through conduit valve designed to meet the requirements of API-6A. It is made with standard flanged outlets but can be modified to have studded outlet configurations. Standard features of the Neeco gate valve are: 1. Minimized operating torque. These valves are built with a ball screw mechanism and have a lower stem which also helps in indicating the gate position. 2. Manufactured to have a metal-to-metal sealing at the gate-to-seat area and designed for dependable sealing by incorporating a simplified slab gate and seat assembly to seal in both directions. This feature helps to reduce the number of parts and simplify field service as well. 4. The stem packing used is of non-elastomeric material for low coefficient of friction and is a pressure energized seal to withstand severe temperatures and fluids. 5. Back seating feature of the upper stem and lower stem allows either stem packing to be replaced if necessary while the valve is under pressure. 6. For safety, these valves are provided with grease fittings located on the downstream side of the upper stem and lower stem back seat shoulders. No lubrication ports extend directly into the valve cavity. 7. The BX-Style metal bonnet gasket used in these valves provides pressure-energized seal between the valve body and bonnet.
OPERATION 1. The gate should be completely opened or closed when installation or shipping is to be done. When the valve is to be stored, the gate should be completely open, thus preventing damage to the sealing mechanism. 2. The molybdenum disulfide coating shall not be removed from the internal parts as the coating serves as a lubricant and corrosion inhibitor. 3. Valve OPENs with the counterclockwise turning of hand wheel and clockwise turning CLOSEs the valve. A 1/4-1/2 counterclockwise turn should be given after closing so as to ensure that the slab gate is floating and sealing. The required input torque may increase for the last few turns if a pressure differential builds across the gate. 4. The valve must be in a partially open position when hydrostatic test is to be conducted on the valve. At the time of testing the valve in closed position, i.e. performing seat test, care should be taken that the recommended working pressure is not exceeded. 5. When servicing on the stem bearing is to be done, the valve should not be in service condition. Note: When required to bleed pressure from the bore, there may be trapped pressure in the cavity when the valve is in the open or closed position. The valve may be cycled or temporarily held in the half open position to relieve this pressure. SIZE NO. OF REVOLUTIONS TORQUES BEFORE CRACKED OPEN 7 1/16-10K 17 ¼ 180 ft-lbs
LUBRICATION 1. The maximum API working pressure should not be exceeded, which can be referred to on the nameplate. 2. During the lubrication of the seats and/or body, the valve must be partially open to allow the grease to spread evenly. 3. Stem bearing is to be lubricated through the 1/2 NPT grease fitting provided on the bonnet. Any No. 3 grease of good grade is recommended. 4. The maximum allowable API test pressure must not be exceeded when lubricating the seats. NAMEPLATE All Neeco Industries valves come with a nameplate attached to them. They are located in the center of the body area. These plates ensure that the specified design has been followed along with strict QC stipulations set by the industry.
PERIODIC MAINTENANCE Neeco NF-700 gate valves do not require the injection of lubricants or sealants to operate effectively or seal properly. But it is highly recommended to periodically lubricate the valve to increase the life and serviceability and also to prevent it from corrosion and excessive wear and tear. Tools for Maintenance 1. Grease pump with adapters and coupling (Please contact Neeco Industries if you don t have proper adapters or couplings) Fig 1 Grease pump with adapter and pistol. 2. Pressure releasing tool Fig 2. Bleeding Valve Neeco 7 1/16-10K Slab gate valves are supplied with 1/2 NPT body fitting connection.
TESTING THE EFFECTIVENESS OF THE BACK SEAT The valves with 10,000 psi WP and below use an NPT thread type of grease fitting, see Figure 3. Figure 3. Grease fitting for 10,000 psi WP and below 1. Remove the cap on the grease fitting. (Refer to Figure 8) 2. Trip the ball in the grease fitting check valve by inserting a 1/8" diameter by 3/4" long pin into the run of the fitting. 3. Replace the cap slowly until the ball in the fitting is unseated and the pressure trapped behind the stem back seat is released. GREASE FITTING REPLACEMENT The upper and lower grease fittings can be replaced while the valve is under pressure only if they are isolated by an effective back seat seal, which has been verified. Replacement of the grease fitting under pressure should be done only when all options of isolating the valve from pressure are exhausted. NOTE: When required to bleed pressure from the bore, there may be trapped pressure in the cavity when the valve is in the open or closed position. The valve may be cycled or temporarily held in the half open position to relieve this pressure.
1. Preparation: a. If the valve is under pressure, both grease fittings cannot be replaced at the same time. The grease fitting on the bonnet can be replaced only if the upper stem passes its back seat test. Similarly, the grease fitting near the stuffing box or bottom of the valve can be replaced only if the lower stem passed its back seat test. b. If the valve was isolated from pressure, use the grease fittings to check and release any pressure trapped inside the valve cavity. 2. Remove the defective grease fitting. 3. Remove the cap from the new grease fitting. If the grease fitting has NPT threads, valves rated at 10,000 psi and below, apply Teflon thread seal tape or thread sealant according to the manufacturer s instructions. If the grease fitting has a straight thread, valves rated at 15,000 psi and above, do not use Teflon tape or thread sealant. Caution: Installing the fitting with the cap in place prevents the fitting from properly seating and could cause damage to the cap. 4. Install the new grease fitting. 5. Install and tighten the cap on the grease fitting. 6. Un-back seat the appropriate valve stem.
GATE AND SEAT REPLACEMENT The valve must be isolated from pressure before the gate and seat can be replaced. Note: When required to bleed pressure from the bore, there may be trapped pressure in the cavity when the valve is in the open or closed position. The valve may be cycled or temporarily held in the half open position to relieve this pressure. I. GATE AND SEAT REMOVAL 1. Isolate the valve from pressure. Release the cavity pressure by bleeding through grease fittings from Top & Bottom bonnets. 2. Close the valve by turning the hand wheel clockwise until it stops, then back off approximately 1/4 to 1/2 turn. 3. Support the bonnet and remove the bonnet nuts 4. Pull the bonnet assembly (along with lower stem) away from the valve body until it clears the bonnet studs. Place the bonnet assembly to the side to disengage the T-slot connection between the upper stem and the gate. Unscrew the lower stem to remove the lower stem. 5. Remove the bonnet gasket to inspect it and the seal groove. If the seal grooves are damaged, contact Neeco for repair. 6. Remove the retainer plates, gate guides, seats and seat seals from both sides. 7. Inspect the gate & seats, seat seals, retainer plates, gate guides, seat pockets of the valve body. 8. Assemble the new gate, lower stem and stem packing. II. GATE AND SEAT INSTALLATION 1. Flush the body cavity thoroughly with a suitable solvent and wipe clean with a rag. Ensure that the body cavity is clean. 2. Apply a thin coat of grease to the seat area inside the body cavity, gate and the seats. 3. Install the two seat seals into the face grooves on each seat. Install the seats into the body seat pockets with the seat seals facing the mating seat pocket. 4. Install Retainer Plates, Gate Guides in the valve cavity.
5. Install the gate into the cavity between the seats and keep the gate T slot above the body face for ease of bonnet installation. 6. Apply a thin film of grease onto the new gasket and the ring groove. Install the new gasket into the groove on the body. 7. Turn the hand wheel counterclockwise to extend the valve stem. Raise the bonnet toward the valve. Align and connect the valve stem and gate at the T-slot connection, then push the bonnet down onto the bonnet studs, while turning the valve hand wheel clockwise slowly. 8. Tighten four evenly spaced bonnet nuts with hand to prevent the bonnet from rising away from the valve body. 9. It is not recommended to tighten nuts without applying thread compound to stud and nuts. Install and tighten all the bonnet nuts evenly to the recommended torque using a star pattern. The bonnet face should fully contact the body face. Few suggestions are given below on thread compounds and torque values for tightening the stud size 1 7/8-8UNC & 2 15/16 Heavy Hex Nut used on this valve. Recommended Torque for Studs Thread Compound Molybedenum Disulfide Moly Graphite Recommended Torque 2775 ft-lbs 3460 ft-lbs
ASSEMBLY INSTRUCTIONS For ease and productivity, we have included the assembly instructions for the NF- 700 valve to ensure a comprehensive understanding of the purchased product for the customer. I. PARTS VIEW 1. Aggregate View of Internal Parts (excluding Bonnet components) 2. Bonnet Seal Rings (Upper/Bottom)
3. Seats w/seals (Note: Two seal areas on each seat) 4. Gate Guides
5. Top Bonnet (Note: Top-Bonnet has external threads) 6. Aggregate View of Top-Bonnet Internal Parts (Note: (2) Spring-Loaded Packing)
7. Ball Screw Assembly
II. ASSEMBLY PROCEDURES A. PRE-ASSEMBLY AND BOTTOM-BONNET 1. Insert studs onto either side of valve body by hand and then snug tight with wrench. 2. Grease and place (1) Bonnet Seal Ring on the groove area atop the valve body.
3. Place bottom bonnet (Stem protector attached) onto the valve body, carefully aligning the bolt holes and the studs. (Note: Bottom bonnet has internal threads). 4. Tighten down the nuts (with wrench) and then torque to 6,000 lbs. 5. Carefully turn over the valve body with bottom bonnet underneath (open end up).
B. TOP-BONNET ASSEMBLY 1. Insert (1) spring loaded packing onto threaded side of top bonnet, as shown in the picture. 2. Screw gland packing onto threaded side of bonnet and tighten.
3. Grease threaded stem (top-bonnet stem) and insert threaded side first into non-threaded end of bonnet, gently tapping the stem until about 1 remaining. Leave clearance to attach gate to stem block area. 4. Place the spacer (black) onto the threaded side of the bonnet, place the bearings on top of the spacer and install the ball screw operator (Note: To ensure ball screws stay in place, carefully screw bottom portion)
5. Insert the stem pin onto bottom portion of stem before tightening down the ball screw on the top bonnet, Place ball bearings over the ball screw portion, and screw the bearing cap onto the bottom.
6. Fully Assembled Top Bonnet
C. VALVE ASSEMBLY 1. Remove any debris and clean both seat pocket areas of the valve body. 2. Insert the inner and outer Teflon seals onto each seat, apply a generous amount of grease and install both seats (Teflon side out) in the seat pocket area of the valve body.
3. Place gate guides over the inserted seats on the valve body. 4. Insert T-Slot gate into the portion of the stem jutting out from the top bonnet and grease the gate.
5. Grease and place the upper bonnet seal ring (Note: Upper/Bonnet BSR are identical) onto valve body. 6. Take the non-threaded stem (bottom-bonnet stem) and fit the T portion onto the bottom part of the T-slot gate attached to the top bonnet, carefully place the fully-assembled top bonnet onto the valve body
7. Insert studs, insert nuts and torque down nuts to 6,000 lbs.
8. Place valve horizontal and remove the stem protector from bottom bonnet Insert (1) spring loaded packing,
Insert back cap (white) all the way into the bonnet, and screw back the stem protector.
DRIFT/HYDRO-TEST/GREASE 1. Drift test the fully-assembled valve by placing the drift plug through the bore area of the valve. 2. Place test flanges on each side of valve flanges with 3 to 4 studs and nuts. Note: Turn the valve to half-open position for purposes of conducting shell test prior to attaching both test flanges.
3. Insert a BX-156 gasket between each side of the valve and test flange before inserting all the studs/nuts and fully tightening with an impact gun 4. Shell Test: (PSL-3 Requirements) a. Insert two hoses, on each test flange, to conduct shell test.
b. Pressure up to 15,000psi for 3 minutes bleed off the pressure until zero, and close pressure release tool. Raise the pressure back up to 15,000psi for 15 minutes bleed off the pressure until zero. Close the pressure release tool and the valve. (Note: PSL-3 requires two separate tests at different intervals). c. If there is no indication of leakage during the holding periods, the valve is acceptable to PSL-3 requirements.
5. Seat Test: (PSL-3 Requirements) a. With the valve closed, pressure up to 10,000psi for 3 minutes, open the valve and bleed off the pressure until zero. Close the valve and the pressure release tool. Pressure up to 10,000psi for 15 minutes, open the valve and bleed off the pressure until zero. Close the valve and the pressure release tool. b. Switch the sides of your flow and pressure release connections, bleed off the new pressure release side and conduct two seat tests identical to 5(a) above on the new flow side. c. If there is no indication of leakage during the holding periods, the valve is acceptable to PSL-3 requirements. 6. Once the valve has been fully tested and the pressure is down to zero, loosen each of the test flanges with an impact gun and remove them from the valve.
7. Grease the flange areas of the valve. The valve is now ready for shipping.