-
Drill Pipe
View Products
Heavy Weight Drill Pipe
View Products
Drill Collar
View Products
Kelly
View Products
Tool Joint
View Products
Surface Protection & Internal Coating
View Products
Specialty Drill Products
View Products
-
-
-
-
Shale Gas Drilling Drill Pipe Procurement Guide: Selection of S135, V150, and DSTJ Grades for Horizontal Wells
Author:
WHH
Source:
LONGWAY
Published:
2026-09-28
Shale gas development primarily employs horizontal wells and extended-reach wells, with horizontal sections typically ranging from 1,500 to 3,000 meters, and in some cases exceeding 4,000 meters. This well configuration imposes technical requirements on drill pipes that far exceed those of conventional vertical wells—namely, high torque capacity, superior fatigue resistance, low friction, and extended service life.
Selecting the wrong drill pipe can, at best, result in low mechanical penetration rates and frequent make‑up and break‑out operations; at worst, it may lead to drill pipe failure and a high incidence of downhole incidents. This paper systematically reviews the technical requirements for drill pipes in shale gas drilling, the rationale behind their selection, and key considerations for inspection and maintenance.
I. Operating Characteristics of Shale Gas Drilling
| Operating Condition Characteristics | Impact on the drill pipe |
| Horizontal section length (1,500–3,000 m+) | High friction, high torque, and difficult transmission of drilling weight. |
| High wellbore curvature (build section) | High bending stress and a high risk of fatigue failure. |
| Rotary drilling in long horizontal sections | The drill pipe continuously rubs against the wellbore wall, causing rapid wear at the joints. |
| Oil-based drilling fluids are commonly used. | The corrosion risk is relatively low, but lubricity requirements are high. |
| Fracturing operations are frequent. | Drill pipes are subjected to cyclic loads, leading to rapid fatigue accumulation. |
| The well depth is considerable (3,000–5,000 m). | High tensile loads require high-strength steel grades. |
II. Core Technical Requirements for Drill Rods
1. High-strength steel grade
The tensile load and torque in shale gas horizontal wells are significantly higher than those in conventional vertical wells. It is recommended to select:
| Steel grade | Minimum yield strength | Applicable Scenarios |
| G105 | 105,000 psi | Medium- and shallow-depth horizontal wells (horizontal section < 1,500 m) |
| S135 | 135,000 psi | Deep horizontal wells, long horizontal sections (preferred option) |
| V150 | 150,000 psi | Ultra-deep wells, ultra-large-displacement wells |
Selection recommendation: When the horizontal section exceeds 1,500 meters, prioritize the S135 steel grade; when it exceeds 3,000 meters or the well depth surpasses 5,000 meters, consider V150.
2. High-torque-resistant joint
In horizontal well drilling, torque is the primary limiting factor. Standard API connections may reach their torque limits in long horizontal sections. Recommended selection:
Double‑shoulder threaded joint (DSTJ): provides 20–50% higher torsional strength than standard API joints.
NC-series threads: large‑size threads such as NC50, NC56, etc., with enhanced torsional resistance.
Cold-rolled threads: Enhance thread fatigue strength
3. Anti-Fatigue Design
The alternating bending stress experienced by drill pipe in horizontal wells is significantly higher than that in vertical wells. Requirements:
The thickened transition zone ensures a smooth transition, reducing stress concentration.
The heat treatment of the weld zone is strictly controlled, ensuring uniform hardness.
Select the NC series threads with excellent fatigue resistance.
4. Wear-resistant belt and friction reduction
Rotary drilling in long horizontal sections results in severe friction between the drill string and the casing/wellbore. Recommendation:
Wear-resistant strip: LW600 or LW700, providing both joint protection and casing protection.
Internal coating: LPC3000P or LPC5000P, reducing drilling fluid flow resistance.
Thread lubricant: Use a high‑lubricity thread lubricant to reduce friction during make‑up and break‑out.
5. Heavyweight Drill Pipe (HWDP) application of
In horizontal wells and extended-reach wells, HWDP is used for:
As the transition section between the drill pipe and the heavy-weight drill pipe.
Provide a flexible transition near the build-up point to reduce stress concentration.
Replace part of the drill collar to reduce friction and the risk of differential sticking.
We recommend using the triple‑helix HWDP, whose helical groove design enhances borehole cleaning and reduces differential sticking.
III. Recommended Bottom-Hole Assembly (BHA) Configuration
Typical BHA configuration for a shale gas horizontal well (from bottom to top):
| Location | Component | Function |
| 1 | PDC drill bit | Rock breaking |
| 2 | Screw Drill/Rotary Steerable System | Provide power and guidance |
| 3 | MWD/LWD | Measure wellbore inclination, azimuth, and formation parameters. |
| 4 | Non-magnetic drill collar | Provide a non-magnetic environment for MWD. |
| 5 | Drill collars (2–4 pieces) | Provide drilling pressure |
| 6 | Impact tool | Unlock card |
| 7 | Heavyweight Drill Pipe (HWDP) | Transition section, reducing stress concentration. |
| 8 | Drill pipe (S135/V150) | Transmit torque and drilling pressure to the ground. |
Key point: The HWDP should be positioned near the build‑up point, with its length determined by the wellbore curvature and the required weight on bit.
IV. Key Points for Inspection and Maintenance
| Test Items | Frequency | Method |
| Thread Inspection | After pulling out of each well | Magnetic Particle Testing (MT) |
| Pipe wall thickness | Every 3–5 wells | Magnetic Flux Leakage (MFL) or Ultrasonic Thickness Measurement |
| Thickened transition zone | Annually or per 5 wells | Ultrasonic Testing (UT) |
| Wear-resistant belt inspection | After each trip out of the hole | Visual inspection + hardness testing |
| Internal Coating Inspection | After each trip out of the hole | Visual inspection + coating thickness measurement |
| Cumulative Fatigue Assessment | Continuous recording | Single Drill Pipe File |
V. Procurement Considerations
When procuring drill pipes for shale gas drilling, the contract should clearly specify:
| Procurement Item | Technical Requirements |
| Steel grade | S135 or V150 |
| Connector Type | Double-shoulder (DSTJ) or NC series large-diameter threads |
| Wear-resistant strip | LW600/LW700, or as per customer requirements |
| Internal coating | LPC3000P/LPC5000P |
| Nondestructive testing | 100% UT+MT, with MTC issued. |
| PSL level | PSL-2 or PSL-3 |
| Traceability | The heat number is consistent with the MTC. |
| Third-party inspection | Supports on-site inspections by SGS/BV. |
VI. Frequently Asked Questions (FAQ)
Q1: Must S135 steel be used for shale gas horizontal wells?
Not necessarily. When the horizontal section is relatively short (<1,500 m) and the well depth is modest, G105 can also suffice. However, if the horizontal section exceeds 1,500 m or the well depth surpasses 4,000 m, it is recommended to use S135.
Q2: How much more expensive is a double‑shoulder coupling compared to a standard coupling?
Double‑shoulder connections typically command a 20–30% premium over standard API joints, yet deliver 20–50% higher torsional strength. In extended horizontal sections, they markedly reduce the risk of joint failure, resulting in superior overall performance.
Q3: How many HWDPs are appropriate to run in a horizontal well?
It is generally recommended to deploy 10–20 HWDPs, with the exact number depending on wellbore curvature, weight‑on‑bit requirements, and drillstring design. The design principle is to position the neutral point within the HWDP or heavy‑weight drill pipe section.
Q4: Does shale gas drilling require an internal coating?
Recommended for use. The internal coating reduces drilling fluid flow resistance, lowers pump pressure, and enhances hydraulic efficiency. It also helps prevent internal corrosion of the pipe body.
Q5: How can you determine whether the drill rod needs to be replaced?
Assessment is conducted through inspection. When cracks are detected in the threads, wall thickness reduction exceeds the allowable limit, or cumulative fatigue damage reaches the threshold, the component shall be downgraded or scrapped.
VII. Summary
| Key point | Core content |
| Operating Condition Characteristics | Long horizontal section, high torque, significant bending stress, and rapid fatigue accumulation. |
| Recommended steel grade | G105 (short horizontal section), S135 (mainstream), V150 (ultra-deep/ultra-large displacement) |
| Connector Type | Double-shoulder (DSTJ) or NC series large-diameter threads |
| Surface Protection | Wear-resistant belt (LW600/LW700) + Internal coating (LPC3000P/LPC5000P) |
| BHA configuration | Drill bit → Stabilizer/rotary steerable system → MWD → Non-magnetic drill collar → Drill collar → Jar → HWDP → Drill pipe |
| Key Testing Points | MT for thread inspection, MFL for pipe body inspection, UT for thickened sections, and wear‑strip inspection. |
| Procurement Requirements | S135/V150, DSTJ, PSL-2/3, complete MTC, third-party inspection |
Shale gas drilling places far higher demands on drill pipes than conventional vertical wells. Proper tool selection, BHA optimization, and enhanced monitoring are essential to ensuring the safe and efficient drilling of horizontal wells.
Do you need to procure high-strength drill pipes or double‑tapered‑shoulder connections for your shale gas drilling project?
Contact Hebei Longway Petroleum Equipment Co., Ltd.
Obtain professional technical consulting
Hebei Longway holds international certifications such as API 5DP and API 7-1, supplies drill pipes in S135 and V150 grades with double‑tapered connections, and supports third‑party inspections.
Leave Message
Consult Our Engineers & Get Fast Official Quotation
Give you the best solution
- Inquiries get a response within 12 hours.
- We are a professional manufacturer with competitive pricing, and we accept all DEM/ODM orders.
- Our after-sales team provides 24/7 technical support; issues are addressed within 24 hours.
- Precision quality, on-time delivery, tailored service.
We can customize high-performance drill pipe assemblies of various sizes according to customer needs.
Contact Us
Telephone
Phone/Wechat
Address
052260, East of Beikou, Yingli Town, Jinzhou County, Shijiazhuang City, Hebei Provice, China.
Get in Touch
* Fill in your phone number and email information, and we will promptly contact you within one business day to address your concerns as soon as possible.
-
-
扫一扫
微信二维码
关注我们
-
E-mail
-
WhatsApp
-
Telephone
-
Business Card