MWD tools

Technical Specifications – MWD Tool Parameters

The following specifications apply to our standard 48 mm (1.89″) slimhole MWD system, compatible with 4‑¾″ through 8‑½″ drill collars. Custom sizes (32 mm through 121 mm outer diameter) available for specialized applications.

Parameter	Specification
Tool outer diameter	48 mm (1.89″) – slimhole; other sizes available
Total length (directional only)	6.8 m (22.3 ft)
Total length (directional + gamma)	8.8 m (28.9 ft)
Inclination accuracy	±0.1°
Azimuth accuracy	±1.0°
Toolface accuracy	±1.0°
Maximum operating temperature	150°C (302°F); high‑temp option 175°C (347°F)
Maximum pressure rating	140 MPa (20,000 psi)
Maximum allowable shock	1000 G, 0.5 ms half‑sine
Maximum allowable vibration	20 G RMS, 15–500 Hz random
Telemetry method	Positive mud pulse (standard); EM telemetry option
Flow rate range	160–900 GPM (10–55 L/s)
Pressure drop (across pulser)	50–200 psi (depending on collar size and mud properties)
Maximum sand content	<1%
Maximum mud density	≤2.2 g/cm³ (≤18.3 PPG)
Power options	Battery (300+ hr) or turbine (flow‑powered, unlimited run time)
Battery type	High‑temperature lithium, field‑replaceable
Survey modes	Single on command / continuous while rotating / programmable
Retrievability	Bottom‑hole retrievable via slickline
Optional gamma module	API range: 0–500 API; accuracy: ±2%
API / ISO compliance	API Q1, API 7, ISO 9001

Product Types – MWD and Related Downhole Tools

Through our Kingdream downhole tool brand, we supply a complete range of MWD and LWD equipment for directional drilling operations. Kingdream is recognized as one of the major global downhole drilling tool manufacturers alongside industry leaders. Our product portfolio includes:

1. MWD Directional & Gamma Systems (48 mm / 4‑¾″ to 8‑½″)

• Complete MWD directional surveying system (inclination, azimuth, toolface)

• Optional natural gamma module for formation evaluation and geosteering

• Battery or turbine power options

• Our 48 mm slimhole MWD system is a proven, stable performer in directional and horizontal drilling applications, compatible with CNPC, Sinopec, and international drilling operations

2. LWD (Logging While Drilling) Modules

• Resistivity tools for formation evaluation

• Azimuthal gamma imaging for geosteering

• Neutron porosity and density tools

• Sonic logging tools

3. Rotary Steerable Systems (RSS)

• Point‑the‑bit and push‑the‑bit configurations

• Real‑time inclination and azimuth feedback

• Enables continuous rotation while steering – reduces tortuosity and improves hole cleaning

4. Downhole Tools and Accessories

• Non‑magnetic drill collars (NMDC) – API and SY/T5144 certified

• Downhole drilling jars – hydraulic and mechanical

• Stabilizers – integral and replaceable sleeve

• Shock subs – axial and torsional isolation

• High‑pressure manifolds – 21 MPa to 140 MPa, 2″ to 5″

5. Surface Systems and Spares

• Pressure transducers, decoding computers, driller monitors

• Batteries, pulsers, sensor modules (field‑replaceable)

• Calibration tools and test fixtures

Application Fields

📐 Directional Drilling

MWD tools are essential for any wellbore that is not perfectly vertical. From single‑build S‑curves to complex 3D trajectories, the driller relies on real‑time inclination and azimuth to follow the plan. Without MWD, directional drilling would require frequent wireline surveys, each requiring a trip out of the hole.

📏 Horizontal Wells (Shale and Tight Gas)

Horizontal drilling demands continuous trajectory updates – the window between the top and bottom of the pay zone may be only a few meters thick. Our MWD tools provide real‑time inclination to keep the wellbore within the target formation. Adding the gamma module allows geosteering: the driller sees formation radioactivity changes and adjusts the trajectory on the fly.

🧭 Extended‑Reach Drilling (ERD)

Extended‑reach wells push the limits of measured depth. Running wireline surveys in long laterals is difficult or impossible due to friction. MWD provides the only practical method for directional control in ERD applications.

⛽ Underbalanced and Air Drilling

Conventional mud pulse systems require a continuous fluid column. For underbalanced drilling with air, foam, or mist, we offer EM‑telemetry MWD systems that transmit through the formation using low‑frequency electromagnetic waves, with effective depth ranges of 1,000–2,000 meters depending on formation resistivity.

🌊 Offshore and Deepwater Drilling

Offshore rigs carry high daily operating costs – any non‑productive time is expensive. Our MWD tools are built for extended run times (battery or turbine options) and offer bottom‑hole retrievability to avoid pulling the entire drill string for tool failures.

🧪 Geothermal and Mining Exploration

High‑temperature wellbores (up to 175°C) and abrasive environments demand rugged MWD equipment. Our tools are rated for extreme conditions and used in geothermal drilling and mining directional boreholes.

Why Choose SJ Petro for MWD Tools?

🏭 Backed by Sinopec – A Trusted State‑Owned Enterprise

SJ Petroleum Machinery Co., Ltd. is a wholly‑owned subsidiary of Sinopec Oilfield Equipment Corporation, one of China’s largest and most respected energy equipment conglomerates. We are a National Hi‑tech Enterprise and one of China’s Top 500 manufacturers, ranked 2nd among China Top 10 Petroleum Drilling and Production Equipment Manufacturers.

👑 Kingdream – A Major Global Downhole Tool Brand

Our Kingdream brand is recognized as one of the major global downhole drilling tool manufacturers, alongside industry leaders such as Baker Hughes, Schlumberger, and Halliburton. Kingdream supplies downhole tools to CNPC, Sinopec, CNOOC, and international oilfields across the Middle East, Central Asia, and Africa.

🔧 Field‑Proven Performance in Chinese and International Oilfields

Our 48 mm MWD system has been described as the "most stable performing equipment domestically”. Thousands of successful runs in China’s major oil basins provide the performance data and reliability record behind our tools.

📋 API and ISO Certified

Our manufacturing processes are API Q1, API 7, and ISO 9001 certified. All MWD tools are manufactured to international standards, with full traceability on materials, electronics, and calibration.

🌍 Global Export Experience

We have supplied downhole tools, drilling rigs, and oilfield equipment to customers in Russia, Kazakhstan, the Middle East, South America, and the United States. Our export team understands international shipping, customs documentation, and after‑sales support requirements.

🔄 Complete Downhole Tool Ecosystem (One‑Stop Supply)

We do not just sell MWD tools. Through the Kingdream brand, we provide a complete downhole tool ecosystem – drill bits, mud motors, MWD/LWD, drilling jars, stabilizers, and non‑magnetic drill collars. You source everything from one manufacturer, with consistent quality and a single point of contact.

Frequently Asked Questions (FAQ)

Q1: What is the difference between MWD and LWD?

A: MWD (Measurement While Drilling) focuses on drilling parameters – inclination, azimuth, toolface, downhole weight and torque. LWD (Logging While Drilling) focuses on formation evaluation – resistivity, gamma ray, neutron porosity, density. Many tools combine both; our MWD systems can be configured with a natural gamma module for basic formation evaluation.

Q2: How deep can your MWD tools work?

A: Depth capability depends on telemetry method and formation properties. For mud pulse telemetry, effective depth exceeds 6,000 meters (20,000 ft) as long as mud properties are within spec and flow rates are adequate. For EM telemetry, effective depth ranges from 1,000–2,000 meters depending on formation resistivity – suitable for underbalanced and air drilling applications.

Q3: How long can the MWD tool stay downhole on battery power?

A: A standard battery pack provides 300+ hours of continuous operation (about 12.5 days). A second battery pack can be added to extend run time. For longer laterals or extended campaigns, we recommend the turbine‑powered option, which generates power from mud flow and has no theoretical run time limit as long as circulation continues.

Q4: How do you handle downhole tool failures – do I have to pull the whole string?

A: Our MWD tools are bottom‑hole retrievable. If a tool fails, you can retrieve it using slickline without tripping the entire drill string. This reduces non‑productive time from days to hours. The latching mechanism engages with standard fishing tools carried on most rigs.

Q5: What is the typical lead time for a complete MWD system?

A: Standard lead time for a complete MWD tool (directional sensors + pulser + surface system) is 8–12 weeks from order confirmation. Spare modules (batteries, pulsers, sensor heads) typically ship in 4–6 weeks. Larger orders or custom sizes may extend lead time – contact us for current delivery schedules.

Q6: What training and support do you provide for MWD tools?

A: We provide:

• Operation and maintenance manuals with each tool shipment

• 2‑day classroom and hands‑on training for your MWD engineers (assembly, calibration, surface system operation, troubleshooting)

• Remote technical support during normal business hours (email and phone)

• On‑site commissioning support for first‑time users (additional fee, travel expenses extra)

Q7: Do your MWD tools work with any downhole motor and bent sub?

A: Yes. The MWD tool is run inside a non‑magnetic drill collar directly above the downhole motor. The toolface reference must be aligned with the bent sub scribe line during assembly. Our surface system includes a toolface offset calibration function to compensate for any angular difference between the MWD sensor and the bent sub.

Q8: Can I integrate your surface system with my existing rig instrumentation?

A: Yes. Our surface computer outputs real‑time survey data via Modbus TCP or RS‑485 for integration with third‑party rig monitoring systems, data aggregators, and remote operations centers. The raw pulse data stream is also available on a separate output for advanced users.