CONTINUOUS CIRCULATION SYSTEM · FECCS 连续循环钻井系统 · FECCS
9,508m

FEODE FECCS — the independently developed valve-type continuous circulation drilling system in China. By maintaining uninterrupted mud circulation during connection make-up, FECCS eliminates pressure spikes and ECD fluctuations across critical formations. Verified at EP21-4-A1H — record-depth offshore well at 9,508 m, a dual national record for depth and horizontal reach — in 2024. 远东 FECCS 是远东自主研发的阀式连续循环钻井系统。通过接立柱过程中持续保持钻井液循环，FECCS 消除关键地层的压力波动与 ECD 跳变。2024年于中国海上深井纪录 EP21-4-A1H（井深 9,508 米、井深与水平位移双项全国纪录）完成验证。

Technical Enquiry 技术咨询 View System Specifications 查看系统参数
3D · AT THE CONNECTION三维演示 · 接立柱

Circulation never stops循环不中断

Illustration: the drill-floor layout is simplified.示意图：钻台布置经过简化。

While drilling: through the top drive钻进时：经顶驱循环

A continuous circulation sub sits at the top of every stand.每柱钻具顶部装有连续循环短节。

At the connection: through the side valve接立柱时：经侧阀循环

Before the top drive breaks out, flow is switched to the sub's side valve. The pumps stay on while the next stand is made up.顶驱卸扣前，钻井液切换到短节侧阀循环；接立柱全程不停泵。

9,508m
ERD MD verified (EP21-4-A1H)超大位移井验证井深
5th gen
In-House Generation第五代自主研发
14
Oil & Gas Discoveries Aided参与发现油气田
APPLICATION ADVANTAGES连续循环钻井技术应用特点及优势

What continuous circulation changes downhole 连续循环，为井下带来四重改变

Extended-Reach Drilling大位移钻井 Managed Pressure Drilling控压钻井 Underbalanced Drilling欠平衡钻井 Air Drilling空气钻井 Deepwater & Ultra-Deepwater深水 / 超深水钻井 Loss- & Kick-Prone, Pressure-Sensitive Wells易喷易漏 · 地层压力敏感井
01CLEAN清洁

Continuous cuttings transport — a cleaner hole连续返屑带砂，井眼更清洁

  • Prevents cuttings-bed build-up, reducing drag, stuck pipe and related complications防止和减少岩屑床形成，减少阻卡等复杂情况
  • No pump-off cuttings settlement and re-grinding — solids control works better避免开停泵造成岩屑反复沉降挤磨，提高固控效果
  • Lower friction and torque — less load on top drive and pump systems, safer operations降低摩阻与扭矩，减轻顶驱和泵系统负荷，提升作业安全性
  • Fewer and shorter wiper trips — more productive rig hours减少短起下钻次数与段长，提高作业效率
Torque fluctuation 2.86 vs 7.40 kN·m · zero wiper trips扭矩波动 2.86 对比 7.40 kN·m · 零通井 PY10-5-A1H — liner ran straight to bottom with no cleanout trip (the offset well spent 41 h on one); Bohai wells cut cuttings 3.8% → 0.4%.PY10-5-A1H 井 — 尾管直接下到底、未通井（邻井通井耗时 41 小时）；渤海井岩屑浓度由 3.8% 降至 0.4%。
02STABLE稳压

Eliminates pressure surges — stable wellbore pressure有效消除压力激动，井眼系统压力稳定

  • Steady wellbore pressure prevents collapse and keeps the hole smooth and in gauge保持井内压力稳定，防止井壁坍塌，保持井眼光滑
  • Effective ECD control prevents surge-induced losses and influx, and eases mud conditioning有效控制 ECD 值，防止压力激动引起的井漏与溢流，利于泥浆性能调整
  • A steady bottomhole pressure allows a lower ECD — faster drilling, better reservoir protection井底压力平稳，可适当降低 ECD 值，提高钻速、保护储层
ECD fluctuation < 2.6% — vs a ~18% jump at a conventional pump restartECD 波动 < 2.6% — 常规停泵再开泵 ECD 突变约 18% EP21-4-A1H held ECD steady through two fault zones; PY10-5-A1H kept ECD within 2.3% across a fault that collapsed the window to 1.20–1.32 g/cm³ — no losses, no influx.EP21-4-A1H 井穿越两条断层 ECD 平稳；PY10-5-A1H 井在密度窗口骤缩至 1.20–1.32 g/cm³ 的断层段 ECD 波动控制在 2.3% 以内 — 无井漏、无溢流。
03SAVE增效

Higher drilling efficiency, lower well cost提高钻井时效，降低钻井成本

  • Fewer downhole incidents — more on-bottom drilling time降低井下复杂情况发生概率，提高钻井时效
  • No hole-cleaning circulation needed before each connection — total connection time across the well drops sharply省去接立柱前停泵循环返砂的等待，全井接立柱总时大幅缩短
Average ROP 19.30 vs 7.66 m/h — about 2.5×平均机械钻速 19.30 对比 7.66 m/h — 约 2.5 倍 PY10-5-A1H vs an offset well without continuous circulation; back-reaming trips up 71% faster on EP21-4-A1H.PY10-5-A1H 井对比未用连续循环的邻井；EP21-4-A1H 井倒划眼起钻提速 71%。
04SMOOTH平稳

Steady borehole conditions — better wellbore quality保障井筒压力平稳，井身质量更优

  • Less interference with directional and steering tools — tighter trajectory control减少对定向与导向仪器的干扰，提高井眼轨迹控制能力
  • Good wellbore quality eases casing running and cementing operations良好的井身质量，利于下套管与固井作业
9,508 m through two faults — no losses, no collapse, no stuck pipe9,508 m 穿越两条断层 — 无井漏、无坍塌、无卡钻 EP21-4-A1H, record-depth offshore well — longest single run 1,744 m; on PY10-5-A1H the φ177.8 mm liner ran straight to bottom with normal cementing returns.EP21-4-A1H 井（中国海上深井纪录）单趟最长进尺 1,744 m；PY10-5-A1H 井φ177.8 mm 尾管直接下到底、固井返出正常。
TECHNICAL HIGHLIGHTS技术亮点

Why FECCS for HPHT and ERD wells 高温高压与超大位移井的 FECCS 不二之选

01

Independently Developed Valve-Type CCS自主阀式连续循环系统

The independently developed valve-type continuous circulation drilling system in China. One of the few providers globally to offer HPV + PLC + Manifold intelligent control for valve-type CCS systems.远东自主研发的阀式连续循环钻井系统。全球少数几家掌握 HPV + PLC + Manifold 智能控制阀式连续循环系统的提供商之一。

02

Anti-Drop Valve Plate Design阀板防脱安全设计

Failure-safe valve plate design — if the plate detaches, it falls into the circulation sub interior rather than into the wellbore, eliminating downhole fishing risk.失效安全阀板设计 — 阀板若脱落，落入循环短节内部而非井筒，杜绝井下打捞风险。

03

Eliminates ECD Fluctuations消除 ECD 跳变

Continuous mud circulation through connection make-up keeps ECD steady — preventing differential sticking, lost circulation, and formation damage in narrow drilling windows.接立柱过程中持续循环维持 ECD 稳定 — 防止差压卡钻、漏失和窄密度窗口井段的储层伤害。

04

Proven ROP & Cost Benefits验证的提速与降本效益

Across field applications, FECCS has delivered an average 18% acceleration in drilling rate of penetration and around 12% reduction in per-well cost — directly improving project economics.在现场应用中，FECCS 平均提速约 18%，单井降本约 12% — 直接改善项目经济性。

THE SCIENCE BEHIND A STEADY ECD稳住 ECD 背后的科学

Theory and field data, validating each other 理论与现场数据，彼此印证

FECCS isn't only a piece of hardware — it rests on a complete, quantitative model of equivalent circulating density. The model is built on standard well-hydraulics theory, and it has been checked against real bottom-hole measurements. The two agree to within 1%. FECCS 不只是一台设备——它背后是一套完整、可量化的当量循环密度（ECD）模型。该模型建立在标准钻井水力学理论之上，并已用真实井底实测数据校核，二者吻合度优于 1%。

Built on API RP 13D power-law hydraulics基于 API RP 13D 幂律水力学模型
The governing equation控制方程
ECD=ESD+ Pannulusg · H
ESD — static mud density静态泥浆密度 Pannulus — annular friction pressure loss环空摩擦压耗 g·H — gravity × true vertical depth重力 × 垂直井深
01

Power-law rheology幂律流变

Flow-behaviour index and consistency are derived from Fann viscometer readings, exactly as specified in API RP 13D — capturing how the mud thins under shear in the annulus.流性指数与稠度系数由范氏粘度计读数按 API RP 13D 推导，精确刻画泥浆在环空剪切下的剪切稀化行为。

na = 0.5 · log(θ300/θ3)
02

Cuttings loading岩屑加载

Drilled cuttings raise the effective density of the annular fluid. Transport efficiency and a volumetric balance give the in-situ concentration and the true circulating density.钻屑提高环空流体的有效密度。由携岩效率与体积平衡求得井内岩屑浓度与真实循环密度。

ρeff = ρ(1−Ca) + ρc·Ca
03

Annular pressure loss环空压耗

Flow regime is determined from the critical velocity, then the laminar or turbulent annular friction loss is integrated section by section — collar and pipe — to the bit.由临界流速判定流态，再分段（钻铤、钻杆）积分层流或紊流环空摩擦压耗至钻头。

Pa = f(PV, YP, V, Dh−Dp, L)
THEORY ✕ FIELD — A WORKED WELL理论 ✕ 现场 — 一口实井
10.31ppg
Model ECD模型计算 ECD
≈
10.39ppg
Field mud-log ECD现场录井实测 ECD

A 12¼″ hole at 3,750 m, 60 L/s, oil-based mud. The model reproduces the measured circulating density almost exactly — the small offset is the lumped bottom-hole assembly, and it is conservative. 12¼″ 井眼、3,750 m、排量 60 L/s、油基泥浆。模型几乎精确复现实测循环密度——微小偏差源于钻具组合的合并简化，且偏保守。

0.8%
deviation between calculated and field-measured ECD — the model is trustworthy.计算值与现场实测 ECD 的偏差——模型可信。
WHY CONTINUOUS CIRCULATION — IN NUMBERS为什么要连续循环 — 用数字说话

The connection surge that breaks narrow-window wells 压垮窄窗口井的，正是接立柱那一下激动

Conventional · pump stops every connection常规作业 · 每次接立柱都停泵

Restart surge spikes the ECD开泵激动，ECD 瞬间跳高

ECD
+0.14 g/cm³
+0.21 g/cm³
Pore孔隙压力Drilling window钻井窗口Fracture破裂压力

While the pump is off for a connection, the mud’s gel structure sets. Restarting the pump must break that gel — a pressure surge of ΔP = 4τ0H/(Dh−Dp). Measured in an offset well drilled without continuous circulation, ECD swung 0.14–0.21 g/cm³ (1.2–1.8 ppg) each time the pump restarted after a stand connection[1] — enough to fracture the formation and lose returns in a tight window. 停泵接立柱期间，泥浆静胶凝结构形成。再开泵须先破胶，产生激动压力 ΔP = 4τ0H/(Dh−Dp)。未用连续循环的邻井实测：每次接完立柱开泵瞬间，ECD 变化 0.14–0.21 g/cm³（约 1.2–1.8 ppg）[1]——在窄窗口足以压裂地层、井漏失返。

FECCS · circulation never stopsFECCS · 循环永不停止

No gel, no surge — ECD stays flat不结胶、无激动 — ECD 始终平稳

ECD
ESD
Pore孔隙压力Drilling window钻井窗口Fracture破裂压力

By circulating continuously through every connection, FECCS never lets the gel set — so there is no break-gel surge. The bottom-hole ECD holds steady inside the window. In the 9,508 m EP21-4-A1H, a conventional pump restart made ECD jump ~18% (1.31 → 1.54 g/cm³); with continuous circulation, the 12¼″ section held ECD fluctuation under 2.6%[2]. FECCS 在每次接立柱全程持续循环，泥浆不结胶——因此不存在破胶激动，井底 ECD 稳稳保持在窗口内。在 9,508 米的 EP21-4-A1H 井，常规停泵再开泵使 ECD 突变约 18%（1.31 → 1.54 g/cm³）；连续循环的 12¼″ 井段 ECD 波动小于 2.6%[2]。

Sources: [1] Zhang Jie et al., Journal of Southwest Petroleum University (Science & Technology Edition), 2018, 40(4): 90–96 — offset well PY11-6-A1H. [2] Zhang Weiguo et al., China Offshore Oil and Gas, 2025, 37(4): 125–133, §2.4 — the paper names the well EP21-X-A1H.出处：[1] 张杰等，《西南石油大学学报（自然科学版）》2018, 40(4): 90–96，邻井 PY11-6-A1H；[2] 张伟国等，《中国海上油气》2025, 37(4): 125–133，§2.4，文中井号写作 EP21-X-A1H。

Run the numbers on your own well用您自己的井跑一遍

Enter geometry, mud rheology and flow rate — get ECD, flow regime, cuttings loading and the connection-surge risk, computed with the same validated model.输入井身结构、泥浆流变与排量，即得 ECD、流态、岩屑加载与接立柱激动风险——由上述同一套验证过的模型计算。

Open the ECD Calculator打开 ECD 计算器
SYSTEM SPECIFICATIONS系统技术参数

Engineered for HPHT environments & long-duration runs 为高温高压环境与长时间连续作业而设计

FECCS Main Unit FECCS 主机参数
Dimensions外形尺寸1,700 × 1,300 × 2,300 mm
Power Supply电源380V · 3φ4W
Motor电机4 kW · Explosion-proof
Frequency Converter变频器Siemens 7.5 kW · 0–650 Hz
Input / Output Coupling输入/输出接口3″–1502 Hammer Union · 70 MPa
Side Circ. Coupling侧循环接口2″–1502 Hammer Union · 70 MPa
High-Pressure Hose高压软管2″–1502 · OD ⌀73 · 52 MPa
Hose Length Options软管长度选配1.5 / 3 / 3.5 / 5 / 7.5 / 10 / 25 m
Plug Valve Grease Pressure旋塞阀注脂压力8,500–10,000 psi
System Test系统试压52 MPa, ΔP ≤ 2 MPa / 15 min
7″ Continuous Circulation Sub 7″ 连续循环短节
Internal Pressure Rating抗内压75 MPa
Side Valve Tension侧阀孔抗拉≥ 500 T
Side Valve Torsion侧阀孔抗扭≥ 135 kN·m
Torsional Strength抗扭强度> 110,000 ft·lb
Tensile Strength抗拉强度> 1,102 klb
Temperature Range耐温范围−30 °C ~ 150 °C
Main Valve Min. Bore主阀最小通径⌀72 mm
Main Valve Max. Flow主阀最大流量4.2 m³/min
Side Valve Min. Bore侧阀最小通径⌀46 mm
Side Valve Max. Flow侧阀最大流量3 m³/min
Internal Blowout Prevention内防喷功能Yes — on abnormal well pressure井下异常压力时可实现
Connection Type扣型Customised to client requirement根据客户需求
Max. Continuous In-Hole Time最长连续入井时间240 hours
Circulation Sub — Sizing Matrix 连续循环短节 — 分尺寸规格表

The 7″ circulation sub is supplied matched to the drill-pipe size in service. Every unit is proof-tested to 1,102 klb tension and 100,000 ft·lb torque before dispatch. 7″ 连续循环短节按在用钻杆尺寸配套供货。每支出厂前均经 1,102 klb 拉伸与 100,000 ft·lb 扭转试验验证。

Cutaway of the FEODE FECCS circulating sub showing the internal blowout-prevention main valve and side circulation port / FECCS 循环短节纵剖结构图，含内防喷主阀与侧向循环通道

Sectional view of the circulation sub — full-bore main valve with internal blowout-prevention capability, and the side port that keeps mud flowing while the connection is broken. 连续循环短节纵剖图——全通径主阀具备内防喷能力，侧向循环通道在卸扣期间维持泥浆流动。

Item项目 For 5″ DP For 5-1/2″ DP For 5-7/8″ DP
Sub weight接头重量115 kg126 kg124 kg
External size接头外部尺寸7″ × 0.85 m7″ × 0.85 m7″ × 0.85 m
External thread tensile strength外螺纹抗拉强度1,265 klb1,184 klb1,200 klb
Thread torsional resistance螺纹抗扭强度81,102 ft·lb77,200 ft·lb94,300 ft·lb
Make-up torque上扣扭矩43,800 ft·lb42,000 ft·lb56,600 ft·lb
Rated internal pressure额定内压强度10,000 psi10,000 psi10,000 psi
Inner main valve min. bore内主阀最小通径⌀72 mm⌀72 mm⌀72 mm
Max. tensile test接头最大拉伸试验1,102 klb1,102 klb1,102 klb
Max. torsion test接头最大扭转试验100,000 ft·lb100,000 ft·lb100,000 ft·lb

✳ Other sizes and connections can be customised to client requirement. ✳ 可根据客户要求定制其他尺寸与扣型。

COMPONENTS & ANCILLARY SYSTEMS系统组成与配套

Everything that goes to the rig floor with it 随系统一并交付的全套配套

FECCS is delivered as a complete package — main unit, circulation sub, sealing elements, connection manifold and the ancillary hardware needed to rig it up. Every pressure-containing component is rated to the same 10,000 psi working envelope. FECCS 以完整成套形式交付——主机、连续循环短节、密封件、连接管汇，以及现场安装所需的辅助装备。所有承压部件按同一 10,000 psi 工作压力等级配置。

FEODE FECCS connecting manifold system with high-pressure union valves and accumulator assemblies / FECCS 连接管汇系统，高压由壬阀组与蓄能器组件

FECCS connection manifold — high-pressure union valve stack and accumulator assemblies, skid-mounted. FECCS 连接管汇系统——橇装高压由壬阀组与蓄能器组件。

Rubber Sealing Elements橡胶密封件

  • Material: HNBR rubber材料：HNBR 橡胶
  • Tensile strength: 25 MPa (3,625 psi)抗拉强度：25 MPa（3,625 PSI）
  • Temperature resistance: −45 °C to 150 °C耐温范围：−45 ℃ ～ 150 ℃
  • Oil resistance: volume change under 5 % after 7 hours immersion in No. 3 standard diesel at 120 °C耐油性能：标准 3# 柴油 120 ℃ 高温煮泡 7 小时，体积变化率小于 5%

Connection Manifold System连接管汇系统

  • Rigid high-pressure lines: union pup joints, union crossovers, 90° union elbows, flanged unions, and J-type / U-type swivel elbows高压硬管线：高压由壬短节、由壬转换接头、90° 弯头、法兰由壬，以及 J 型与 U 型活动弯头
  • Connections: 2″–3″ 1502 unions with matching flanges — rated 10,000 psi接口规格：2″～3″-1502 由壬接头，配套法兰——额定工作压力 10,000 psi
  • Flexible high-pressure hose: 2″–1502 union, rated 7,500 psi高压软管：2″-1502 由壬接头，额定工作压力 7,500 psi
  • Hose lengths available: 1.5 / 3 / 3.5 / 5 / 7.5 / 10 / 25 m可提供长度规格：1.5 / 3 / 3.5 / 5 / 7.5 / 10 / 25 米

Ancillary Systems辅助系统

Extended Links加长吊环

  • 350 t (350 T) capacity — 3.75 m long350 吨（350T）——3.75 米长
  • 500 t (500 T) capacity — 3.75 m long500 吨（500T）——3.75 米长

Dedicated Mud Bucket专用泥浆防喷盒

  • Top bore sizes 5″, 5-1/2″ and 5-7/8″ — matched to the drill pipe in service顶孔尺寸 5″、5-1/2″、5-7/8″ 等，适配不同尺寸钻杆
PRODUCT GENERATIONS产品迭代历程

Five generations of in-house R&D 五代完全自主研发

2011
1st Generation第一代
2013
2nd Generation第二代
2016
3rd Generation第三代
2018
4th Generation第四代
2024
5th Generation第五代
SELECTED CASE STUDIES典型作业案例

Validated across the South China Sea & Bohai basins 南海与渤海全海域实战验证

FLAGSHIP · FLAGSHIP · 9,508 M OFFSHORE WELL 旗舰案例 · 中国海上深井纪录
EP21-4-A1H
9,508 m
Measured Depth · Dual National Record井深 · 双项全国纪录

Enping 21-X field, Hailong 9 platform — record-depth offshore well, setting national records for both depth and horizontal reach (HD/TVD 4.43). 12-1/4″ section drilled 4,594–8,131m + 8-1/2″ section 8,131–9,508m. 164 XT57 circulation subs deployed; single-run distance 1,744m — record-setting. ECD held steady at 1.34–1.45 sg through two fault crossings; connection time reduced to 8–9 min. 恩平 21-X 油田，招商海龙九平台 — 中国海上深井纪录，创井深与水平位移双项全国纪录（水垂比 4.43）。12-1/4″ 井段钻进 4,594–8,131m + 8-1/2″ 井段 8,131–9,508m。投运 XT57 循环短节 164 个；单趟钻进 1,744m — 创纪录。穿越两条断层段 ECD 稳定在 1.34–1.45 sg；接立柱时间提效至 8–9 分钟。

BOHAI FIRST DEPLOYMENT 渤海首次应用
JZ25-1-B7 / B22P1
88%
Cuttings Cleaning Efficiency岩屑净化效率

July–August 2021. First FECCS deployment in the Bohai Basin. 8-1/2″ hole section 3,906–5,001m (length 1,095m). Cuttings concentration reduced from 3.8% to 0.5%, delivering 88% cleaning efficiency and stable hole conditions through highly faulted sections. 2021年7-8月。渤海盆地首次部署 FECCS。8-1/2″ 井眼 3,906–5,001m（段长 1,095m）。岩屑浓度由 3.8% 降至 0.5%，净化效率达 88%，复杂断裂带井段井况保持稳定。

ERD APPLICATION · 2.5× ROP 大位移井应用 · 机械钻速2.5倍
PY10-5-A1H
19.30 m/h
Average ROP — vs 7.66 without CC平均机械钻速 — 未用连续循环仅 7.66

Panyu Oilfield's hardest ERD well (7,646 m MD, HD/TVD 2.76, full-section oil-based mud, a fault collapsing the window to 1.20–1.32 g/cm³). Continuous-circulation-valve drilling over the φ215.9 mm section held ECD within 2.3% and capped torque fluctuation at 2.86 kN·m — versus an offset well, ROP rose 2.5× and the φ177.8 mm liner ran straight to bottom with no cleanout trip (the offset well spent 41 hours on one). 番禺油田高难度大位移井（井深 7,646m、水垂比 2.76、全井段油基钻井液、断层使密度窗口收窄至 1.20–1.32 g/cm³）。连续循环阀钻井应用于 φ215.9mm 井段，ECD 波动控制在 2.3% 以内、扭矩波动仅 2.86 kN·m — 对比邻井机械钻速提升 2.5 倍，φ177.8mm 尾管直接下到底、未通井（邻井通井耗时 41 小时）。

Peer-reviewed. Documented in China Offshore Oil and Gas (2025) and the Journal of Southwest Petroleum University (2018). 同行评审佐证。相关应用发表于《中国海上油气》（2025）与《西南石油大学学报》（2018）。

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circulation drilling system video. 观看 FECCS
连续循环钻井系统视频

Technical Enquiry 技术咨询

Key Facts at a Glance关键事实速览 · Updated July 2026

System系统FECCS continuous circulation, 5th gen
Control控制One-key flow-path + PLC
Circulation sub rated pressure循环短节额定压力10,000 psi
High-pressure hose rating高压软管额定压力7,500 psi
Drill pipe sizes supported适配钻杆尺寸5″ · 5-1/2″ · 5-7/8″
Temperature range耐温范围−30 °C ~ 150 °C
ERD case measured depth大位移案例井深9,508 m
ECD fluctuation, 12¼″ sectionECD 波动（12¼″ 井段）under 2.6% (vs ~18% jump at a conventional restart)小于 2.6%（常规开泵突变约 18%）
Back-reaming improvement倒划眼提升~71%
Frequently Asked Questions →常见问题 →