Product Overview

DEENPU FC SMLR Gate Valve — Full Bore Through Conduit Design with Non-Rising Stem and Floating Slab Gate

The DEENPU FC SMLR Gate Valve is a field-proven, API 6A compliant gate valve designed for wellhead, manifold, and production system applications in the oil and gas industry. The valve features a non-rising stem with a slab gate full bore through conduit design, providing a straight, unobstructed flow path when fully open that minimizes pressure drop and turbulence. The floating slab gate and floating seat ring body bushing design ensures safe, dependable service by allowing the gate and seats to self-align under pressure, providing uniform metal-to-metal sealing contact across the full sealing surface.

DEENPU FC SMLR Gate Valves are available in working pressures from 2,000 PSI (2M) through 20,000 PSI (20M) and bore sizes from 1-13/16″ through 7-1/16″, covering the full range of API 6A wellhead and manifold applications. The valve is available with both threaded end and flanged end connections, with dimensions and pressure ratings compliant with API 6A and ASME B16.5 standards. The non-rising stem design minimizes the operational space required above the valve, while the floating seat design allows for reliable sealing even under thermal expansion and pressure fluctuations.

A unique feature of the FC SMLR design is the stem pin shear protection — the stem pin is designed to shear if the hand wheel is over-torqued, protecting the stem and internal parts from failure. The one-piece slab gate helps prevent line sediment from entering the body cavity and prevents pressure locks when the upstream pressure drops. The valve is available in a wide range of body and trim materials to meet various operating conditions, including sweet service, sour service (H2S), and high-temperature applications.

How the FC SMLR Gate Valve Works

The FC SMLR gate valve operates through a unique floating slab gate mechanism that provides reliable sealing and long service life in demanding oilfield conditions:

1. Full Bore Through Conduit Design — When the valve is fully open, the slab gate is completely retracted into the bonnet, leaving a straight, unobstructed bore through the valve body that matches the internal diameter of the connecting pipe. This full bore design provides several advantages: minimal pressure drop across the valve (typically less than 0.5 PSI at maximum flow rate), reduced turbulence and erosion of the valve internals, ability to pass pigs and scrapers through the valve for pipeline cleaning, and no flow restriction that could cause cavitation or vibration. The through conduit design is particularly important in production manifolds and pipeline applications where flow efficiency and pigging capability are critical. The slab gate is a single, flat piece of precision-machined steel that slides perpendicular to the flow direction, providing a simple, reliable sealing mechanism with minimal moving parts.
2. Floating Slab Gate and Seat Design — Unlike conventional wedge gate valves where the gate is forced into the seats by stem torque, the FC SMLR uses a floating slab gate and floating seat rings. The gate is free to move slightly within the body cavity, and the seat rings are spring-loaded or pressure-energized to maintain contact with the gate. When the valve is closed, the line pressure acts on the gate and seats to push them together, creating a pressure-assisted seal. The floating design allows the gate and seats to self-align and compensate for thermal expansion, pressure deformation, and minor misalignment. This ensures uniform sealing contact across the full sealing surface, preventing the localized wear and leakage that can occur with rigid gate designs. The seat rings are fitted with O-rings or gaskets to seal against the body, and the metal-to-metal contact between the gate and seats provides the primary pressure seal. The floating design also allows for easy in-line maintenance: the gate and seat assembly can be removed and replaced without removing the valve from the line, using standard tools.
3. Stem Pin Shear Protection and Back Seat Sealing — The FC SMLR features a stem pin that connects the hand wheel to the stem. If the operator applies excessive torque (e.g., by hammering on the hand wheel or using a cheater bar), the stem pin is designed to shear at a predetermined torque, preventing damage to the stem threads, gate, and seats. This is a critical safety feature that protects the valve from catastrophic failure due to over-torquing. The valve also features a stem back seat — a conical seal surface on the stem that pushes against the bonnet when the valve is fully open. This back seat creates a metal-to-metal seal that isolates the stem packing from the line pressure, allowing the stem seal (packing) to be replaced while the valve is still under pressure. This is an essential feature for production applications where the valve cannot be depressurized for maintenance. The stem back seat also provides a secondary seal in the event of packing failure, preventing external leakage and potential safety hazards.

Key Features

Applications

• Wellhead production valves — Master valve, wing valve, and swab valve on Christmas trees and wellhead assemblies for production flow control
• Choke and kill manifolds — Isolation valves on choke manifold, kill manifold, and well control system piping for high-pressure shutoff
• Production manifolds — Flowline isolation, header valves, and test line valves on production and test manifold systems
• Pipeline isolation — Full bore design allows pigging. Ideal for pipeline block valves, launcher/receiver valves, and station isolation
• Water injection systems — High-pressure isolation valves on water injection wellheads and injection manifold systems
• Gas lift systems — Gas lift manifold valves, gas supply line valves, and wellhead gas lift valves
• Well testing and workover — Temporary and permanent valves on test manifolds, workover BOP stacks, and well service lines
• High-pressure fracturing and stimulation — 10M, 15M, and 20M valves for fracturing manifold, stimulation lines, and high-pressure pumping systems

Flanged End FC SMLR Gate Valve Dimensions — 2,000 PSI

Flanged End FC SMLR Gate Valve Dimensions — 3,000 PSI

Flanged End FC SMLR Gate Valve Dimensions — 5,000 PSI

Flanged End FC SMLR Gate Valve Dimensions — 10,000 PSI

Flanged End FC SMLR Gate Valve Dimensions — 15,000 PSI

All dimensions approximate per API 6A 21st Edition. Flange face-to-face dimensions vary with flange type (6B vs 6BX) and ring gasket type. Weights shown are approximate for standard carbon steel construction. Contact us for exact dimensions, weights for alternative materials, and custom configurations. 20M (20,000 PSI) ratings available on request for selected sizes.

Threaded End FC SMLR Gate Valve Dimensions — 2,000 PSI

Threaded End FC SMLR Gate Valve Dimensions — 3,000 PSI

Threaded End FC SMLR Gate Valve Dimensions — 5,000 PSI

Threaded end connections: API line pipe or tubing threads. A = Thread face to face. B = Bore centerline to bottom of valve. C = Bore centerline to handwheel top. D = Handwheel diameter. All dimensions per API 6A. Contact us for non-standard sizes and custom configurations.

When Ordering, Please Specify

1. Valve SizeStandard bore sizes: 1-13/16″, 2-1/16″, 2-9/16″, 3-1/8″, 3-1/16″, 4-1/16″. Custom sizes available on request.
2. Working Pressure Rating2M (2,000 PSI), 3M (3,000 PSI), 5M (5,000 PSI), 10M (10,000 PSI), 15M (15,000 PSI), or 20M (20,000 PSI). Select based on maximum anticipated operating pressure.
3. End Connection TypeThreaded end (API line pipe or tubing thread) or flanged end (API 6B or 6BX flange). Specify thread type or flange size and pressure rating.
4. Ring Gasket Type (for flanged valves)BX (for 6BX flanges), RX (for 6B flanges), or R (for type 6B flanges). Specify based on mating flange configuration.
5. Material GradeAPI 6A material grade: AA, BB, CC, DD, EE, FF, or HH. For sour service, specify NACE MR0175 compliant grade. For low-temperature service, specify impact test requirements.
6. Material SpecificationCarbon steel (AISI 4130/4140), low-alloy steel, or stainless steel (duplex, super duplex). Specify for corrosive or high-temperature environments.
7. Trim MaterialGate and seat trim material: 410 SS, 316 SS, Inconel, or Stellite hardfacing. Specify for abrasive or corrosive service.
8. Operator TypeHandwheel (standard), chainwheel (for elevated installations), gear operator (for high-torque or motor actuation), or pneumatic/hydraulic actuator.
9. Service ConditionGeneral (sweet) service or Sour Service (H2S). Specify H2S partial pressure, CO2 content, and temperature for sour service material selection.
10. Certification RequirementsAPI 6A certification, material test certificates (MTC), hydrostatic test certificates (shell and seat), NACE MR0175 compliance certificate, and third-party inspection (DNV, BV, SGS).

Custom Manufacturing & OEM Capability

• Non-Standard Sizes — Custom bore sizes, face-to-face dimensions, and overall dimensions manufactured to customer specifications for retrofit and replacement applications.
• Special Material Grades — Duplex stainless steel (2205, 2507), super duplex, Inconel, Monel, and other corrosion-resistant alloys for extreme sour service and high-temperature applications.
• Actuator-Ready Configuration — Valve prepared for pneumatic, hydraulic, or electric actuator mounting with ISO 5210 mounting flange, stem extension, and position indicator.
• Locking and Safety Devices — Stem locking devices, mechanical stop locks, and safety interlocks for critical isolation applications where accidental operation must be prevented.
• Extended Bonnet / Cryogenic Service — Extended bonnet design for cryogenic service, LNG applications, and extreme cold environments to prevent stem packing freeze-up.
• Special Coating and Surface Treatment — Internal cladding (Inconel 625 or 316L overlay), PTFE coating, epoxy coating, or hard chrome plating for corrosion resistance and reduced friction.
• Special Testing — Gas testing (helium or nitrogen leak test), cryogenic testing, fire-safe testing (API 6FA), and high-cycle endurance testing beyond standard API 6A requirements.
• Complete Valve Package — Valve supplied as part of a complete wellhead assembly including casing heads, tubing heads, Christmas trees, and manifolds.

Quality Control & Testing Standards

• Material chemical composition verified per heat. Carbon, manganese, chromium, nickel, molybdenum, and sulfur content verified against API 6A material grade requirements.
• Material mechanical properties tested per heat including tensile strength, yield strength, elongation, and hardness per API 6A.
• Impact testing at specified temperature for low-temperature service per API 6A and ASTM A370.
• Each valve shell hydrostatically tested to 1.5x rated working pressure per API 6A. Hold time and leak rate recorded on test certificate.
• Each valve seat hydrostatically tested to 1.1x rated working pressure in both directions. Zero leakage acceptance criterion.
• Gas seat test (optional) at 80% of rated working pressure using nitrogen or helium for critical applications. Leak detection by bubble test or pressure decay.
• Dimensional inspection of bore diameter, face-to-face dimension, flange dimensions, handwheel diameter, and overall height per API 6A tolerances.
• Gate and seat contact surface inspection with dye penetrant or magnetic particle inspection to verify integrity of sealing surfaces.
• Stem thread and thrust bearing inspection for proper fit, torque, and smooth rotation.
• Material test certificates (MTC) per EN 10204 3.1 provided for all valve body, bonnet, gate, and seat materials.
• Third-party inspection and certification by DNV, BV, SGS, or ABS available upon request.

Frequently Asked Questions