Product Overview
The Big ID Flapper Check Valve is a dedicated safety valve matched for coiled tubing downhole service, generally connected to coiled tubing connectors to deliver critical anti-backflow protection. When the coiled tubing string or ground surface equipment suffers damage or failure, this flapper check valve can effectively block reverse flow of downhole well fluid into the coiled tubing, avoiding secondary safety hazards caused by fluid backflow.
This valve adopts independent flapper sealing structure with full large inner diameter flow channel, which allows free passage of balls and plugs, without blocking operation tools during construction. It is widely applicable to heavy-load coiled tubing downhole operations, including sand washing, well cleaning, gas lifting and other conventional intervention treatments. Two complete service grades are supplied to match diverse reservoir environments: STD standard grade for conventional sweet oil wells without hydrogen sulfide corrosive media, and H2S sour service grade constructed with sulfur-resistant alloy for high-H2S corrosive sour gas well working conditions.
The standardized product lineup covers outer diameter sizes ranging from 1-3/4" to 3-1/2", with matched inner diameter and make-up length specifications, equipped with standard AMMT and PAC bottom connection threads for universal compatibility with mainstream coiled tubing connectors and downhole service tools. Custom inner bore sizes, wall thickness and anti-sulfur passivation coatings are available upon customer technical drawing submission.
Complete Technical Specification Table
| PN Part Number | Outer Diameter OD | Inner Diameter ID | Make-Up Length | Working Condition Grade | Bottom Connection Thread |
|---|---|---|---|---|---|
| L1291750120 | 1-3/4" | 0.75" | 10.3" | STD Standard | 1" AMMT |
| L1292125120 | 2-1/8" | 1" | 10.3" | STD Standard | 1-1/2" AMMT |
| L1292875120 | 2-7/8" | 1.38" | 13.4" | STD Standard | 2-3/8" PAC |
| L1293500120 | 3-1/2" | 1.38" | 14.6" | STD Standard | 2-3/8" PAC |
| L1291750320 | 1-3/4" | 0.75" | 10.3" | H2S Sour Service | 1" AMMT |
| L1292125320 | 2-1/8" | 1" | 10.3" | H2S Sour Service | 1-1/2" AMMT |
| L1292875320 | 2-7/8" | 1.38" | 13.4" | H2S Sour Service | 2-3/8" PAC |
| L1293500320 | 3-1/2" | 1.38" | 14.6" | H2S Sour Service | 2-3/8" PAC |
Core Features & Advantages
Reliable metal-to-metal hard sealing structure, forming stable zero-leakage sealing barrier under high wellbore pressure, long service life and strong anti-fluid erosion performance
Full big inner diameter full-bore flow channel design, no flow limiting structure inside the valve body, realizing unobstructed full bore access for balls, plugs and other intervention tools
Independent flapper one-way non-return structure, instant automatic closing under reverse fluid pressure, rapidly cutting off well fluid backflow to protect coiled tubing and surface equipment from damage
Dual service grade design: STD standard version for conventional sweet oilfield working conditions, H2S sulfur-resistant alloy version for highly corrosive high-H2S sour gas well service
Complete outer diameter series compatible with 1-3/4", 2-1/8", 2-7/8" and 3-1/2" coiled tubing matching assemblies, covering all mainstream small and medium-size coiled tubing heavy-load downhole service demands
Simple external threaded connection design, convenient for quick disassembly and assembly with various coiled tubing connectors on site
Precision CNC machined high-strength alloy steel valve body, excellent abrasion, erosion and pressure fatigue resistance to extend continuous long-term downhole safety service cycle
Customizable outer diameter, inner bore flow size, bottom thread specification and anti-sulfur surface passivation coatings to satisfy unique proprietary coiled tubing safety protection requirements
Application Scenarios
1. Coiled tubing sand washing, well cleaning and gas lifting heavy-load downhole intervention treatments
2. Conventional sweet crude oil well coiled tubing intervention safety protection service (STD standard service grade)
3. High-H2S sour gas well corrosive environment coiled tubing string and surface equipment anti-backflow protection operations (H2S sour service grade)
4. Downhole ball dropping, plug launching and other through-tubing intervention construction requiring unobstructed full bore passage
5. Long-term safety protection for coiled tubing strings and ground surface equipment in onshore and offshore oilfields
Standard Delivery Package
Complete big ID flapper check valve main body with built-in metal-to-metal flapper sealing assembly
Matching metal sealing spare parts kit for field maintenance and replacement
Full factory inspection test report including pressure resistance, sealing leakage and flapper closing response test data
Product dimension drawing and official installation & operation instruction manual
Quality Warranty & After-Sales Service
Warranty Coverage: 12 months after factory shipment or 2000 cumulative working hours, whichever condition is reached first.
Full factory inspection: Each finished big ID flapper check valve passes pressure resistance, sealing leakage and flapper closing performance testing before delivery.
Free professional technical support: Our oilfield downhole tool engineering team provides connector matching, installation guidance and parameter consultation free of charge.
Long-term spare parts supply: All metal sealing wear parts and valve accessories are stocked with competitive factory bulk pricing.
Custom development service: Support custom bottom thread profiles, anti-corrosion coatings and special size big ID flapper check valves based on customer technical drawings.
FAQ
Q1: What is the core function of a Big ID Flapper Check Valve?
A1: The Big ID Flapper Check Valve is a coiled tubing safety valve connected to coiled tubing connectors. It automatically closes to block well fluid backflow into coiled tubing when the tubing string or surface equipment fails, protecting equipment from reverse fluid damage.
Q2: What are the two core structural advantages of this flapper check valve?
A2: It adopts metal-to-metal hard sealing for reliable zero-leakage sealing under high pressure; meanwhile, full big ID full bore design allows unobstructed passage of balls and plugs without blocking construction tools.
Q3: What range of outer diameter sizes do these big ID flapper check valves support?
A3: Our standard production lineup fully covers 1-3/4", 2-1/8", 2-7/8" and 3-1/2" outer diameter specifications, compatible with global mainstream small and medium-size coiled tubing matching assemblies.
Q4: What is the difference between STD standard grade and H2S sour service grade?
A4: STD standard grade is manufactured for conventional sweet oil wells without hydrogen sulfide corrosive fluid. H2S sour service grade adopts sulfur-resistant alloy substrate and special anti-sulfur passivation coating to resist chemical corrosion in high-H2S sour gas well environments.
Q5: What is the standard production lead time for bulk purchase orders?
A5: All standard PN part numbers are kept in factory inventory, goods can be delivered within 7-15 working days. Customized big ID flapper check valves with special anti-sulfur coatings or custom flow bore dimensions require 20-35 working days production cycle, subject to total order quantity.
Get Custom Datasheet & Factory Quote
We are a professional OEM & ODM manufacturer focused on full series coiled tubing downhole service tools, covering big ID flapper check safety valves, grapple dimple composite connectors, grub screw heavy-duty connectors, double dimple-on connectors, single dimple-on connectors, double roll-on connectors, single roll-on connectors, internal grapple connectors, external grapple connectors, logging heads and tubing hangers. Every finished product undergoes strict factory pressure resistance, sealing and flow channel testing, with complete material inspection certification attached to each shipment. Please share your detailed technical requirements, including target outer diameter size, working environment (STD standard or H2S sour service) and customized specification demands. Our dedicated oilfield downhole tool engineering team will send complete detailed technical datasheets and competitive factory wholesale quotations within 24 business hours.
