Stepping system

Technical Specifications – Stepping System Parameters

The following specifications reflect typical stepping system capabilities for land drilling rigs. Actual parameters depend on rig weight, pad layout, and customer requirements.

Parameter	Standard Stepping	Heavy‑Duty / Arctic
Load capacity per lift point	150–500 tons (136–454 tonnes)	250–750 tons (227–680 tonnes)
Number of lift points	4–6 (depending on rig size)	4–6 (reinforced)
Vertical lift height per cycle	100–150 mm (4–6 inches)	100–150 mm (4–6 inches)
Horizontal traverse per cycle	300–1,200 mm (1–4 feet)	300–1,200 mm (1–4 feet)
Walking speed	9–30 m/hr (30–100 ft/hr)	9–30 m/hr (30–100 ft/hr)
Cycle time (full lift‑traverse‑lower‑reset)	1–2 minutes	1–2 minutes
Leveling accuracy (during walking)	±0.2 degrees (automatic)	±0.2 degrees (automatic)
Movement directions	Forward/reverse (standard)	X‑Y‑rotation (turntable option)
Maximum travel distance	Unlimited (repeating cycles)	Unlimited
Control interface	PLC with HMI, remote pendant option	PLC with HMI, cold‑hardened displays
Hydraulic pressure	2,500–3,000 psi (17–21 MPa)	2,500–3,000 psi
Cylinder type	Single‑acting ram (lift); double‑acting (traverse)	Single‑acting ram with low‑temp seals
Position feedback	Linear displacement transducers (LDTs), ±0.5 mm accuracy	LDTs with cold‑rated electronics
Operating temperature	-20°C to +50°C	-45°C to +50°C
Ground bearing pressure (walking)	≤7,500 lb/ft² (≈36,600 kg/m²) typical	Same, with larger footings optional
API compliance	API 4F, API 7K	API 4F, API 7K
Typical rig compatibility	ZJ40–ZJ90 AC VFD rigs	ZJ40–ZJ90 Arctic‑rated rigs

Product Types – Stepping Systems from SJ Petro

We offer stepping systems as an integrated option on our drilling rigs or as retrofit kits for existing equipment.

1. Integrated Stepping System (New Rigs)

• Built into the substructure during manufacturing

• Fully tested at our 50,000‑square‑meter assembly yard before shipment

• Includes all lift cylinders, traverse cylinders, PLC control, HMI, and interlock logic

• Available on ZJ40 through ZJ90 AC VFD rigs

2. Retrofit Stepping System (Existing Rigs)

• Designed for rigs already in the field

• Site survey to assess substructure compatibility

• Bolt‑on lifting feet and cylinder mounting points—no major structural modification required

• On‑site installation and commissioning by SJ Petro engineers

• Lead time: 6–8 months from survey

3. Turntable Steering Package (Multi‑Directional Walking)

• Adds hydraulic steering cylinder and turntable assembly to the base stepping system

• Enables 360‑degree rotation and diagonal movement

• Essential for multi‑row pad layouts and off‑axis well spacing

4. Arctic Stepping System (Low‑Temperature Configuration)

• Cold‑hardened hydraulic seals and fluids rated to -45°C

• Heated control enclosures and fluid reservoirs

• Low‑temperature impact‑tested structural steel

• Designed for Siberian, Canadian Arctic, and Alaskan drilling campaigns

Application Fields – Where Stepping Systems Deliver Value

Multi‑Well Pad Drilling (Shale, Tight Gas, CBM)

When you are drilling 20 to 40 wells from a single pad, conventional rig moves are economically impossible. Stepping systems reduce well‑to‑well move time from 2–5 days (conventional rig‑down/rig‑up) to 2–4 hours (hydraulic walking).

Operators report 10–15% reduction in total pad drilling days when using walking rigs versus conventional move methods.

Offshore Island and Platform Drilling

Artificial islands and fixed platforms have limited real estate and high daily operating costs. Stepping systems allow the rig to occupy a single pad position while walking between pre‑set wellheads across the platform deck. Each well is drilled from the same assembled rig—no disassembly, no marine transport between wells.

Arctic and Permafrost Cluster Drilling

Building multiple pads in permafrost is expensive, environmentally intrusive, and often impossible during winter seasons. One Arctic‑rated walking rig on a single pad can drill all wells in a cluster, moving between wellheads while the rig remains heated and operational. SJ Petro stepping systems are proven in Siberian operations at -45°C.

Workover and Re‑Entry Campaigns

Workover rigs servicing multiple wellheads in a field benefit from stepping systems designed for lighter loads. The rig walks from wellhead to wellhead, performing interventions without breaking down. A semi‑automated stepping system with wireless remote control is standard.

Why Choose SJ Petro for Your Stepping System?

Over 50 Years of Rig Manufacturing – We Know the Platform

A stepping system is only as good as the substructure it attaches to. SJ Petro designs and manufactures the drilling rig itself—the mast, the drawworks, the AC VFD drive system, and the substructure. Our stepping systems are engineered specifically for our rigs, not generic bolt‑ons for unknown platforms.

We are ranked No.2 among China Top 10 Petroleum Drilling and Production Equipment Manufacturers and rated AAA by China Petrochemical Industry and Banks.

API 4F and API 7K Certified

All SJ Petro drilling rigs—including stepping systems integrated into them—are designed, manufactured, and tested to API Spec 4F (drilling and well servicing structures) and API Spec 7K (drilling equipment). We hold current API monogram licenses and welcome third‑party inspection.

Field‑Proven in Extreme Conditions

Our low‑temperature stepping systems have been proven in Siberia for Rosneft drilling campaigns at -45°C continuous operation. We operate one of China's few national‑level low‑temperature impact testing laboratories, qualifying structural materials down to -60°C.

Integrated Control – One HMI for Rig and Walk

Our stepping systems are controlled from the same PLC and HMI that manage drawworks, top drive, and mud pumps. The driller does not learn a second interface. Movement commands, position feedback, and leveling status appear on the same touchscreen used for drilling operations.

Global Export Track Record – Over 30 Countries

SJ Petro equipment operates in over 30 countries, including Russia, Kazakhstan, the United States, Canada, the Middle East, and Southeast Asia. We provide complete export documentation, including API certification packages and GOST certificates for Russian/Eurasian markets.

Frequently Asked Questions (FAQ)

Q1: What is the difference between a stepping system and a conventional skidding system?

A: A conventional skidding system typically moves the rig in discrete strokes using hydraulic cylinders pushing against fixed skid beams. Movement is generally straight‑line. A stepping system lifts the rig completely off its foundation, then traverses on rollers or skid pads before resetting. Stepping systems offer finer positioning control, lower ground bearing pressure, and can accommodate multi‑directional movement with turntable options.

Q2: How fast can a stepping system move the rig between wells?

A: Walking speeds typically range from 30 to 100 feet per hour (9 to 30 meters per hour). For a typical well spacing of 15–20 feet (5–6 meters), the move takes approximately 15–30 minutes, plus positioning time. Compare this to conventional rig‑down/rig‑up moves that take 2–5 days.

Q3: Can a stepping system turn the rig or only move it straight?

A: Standard stepping systems move forward and backward. With an optional turntable steering package (hydraulic steering cylinder and turntable assembly), the rig can rotate 360 degrees and move diagonally across multi‑row pad layouts.

Q4: What is the maximum rig weight a stepping system can handle?

A: SJ Petro stepping systems are designed for rig gross weights consistent with our ZJ40 through ZJ90 depth capacities. Industry walking systems have supported loads exceeding 25 million pounds (approx. 11,340 tonnes) across multiple modules. Contact our engineering team with your rig specifications for a load assessment.

Q5: Can a stepping system be retrofitted to an existing rig?

A: Yes. We offer retrofit stepping systems for existing SJ Petro rigs and, after site survey, for third‑party rigs. The retrofit includes bolt‑on lifting feet, hydraulic cylinders, PLC controls, and on‑site installation. Lead time: 6–8 months from survey completion.

Q6: How does the stepping system handle uneven ground?

A: The PLC uses continuous feedback from tilt sensors and individual cylinder LDTs to maintain level. If the rig begins to tilt beyond ±0.2 degrees, the system pauses and adjusts cylinder strokes individually before proceeding. For significantly uneven ground, we recommend foundation leveling or larger lifting feet to distribute bearing pressure.

Q7: Do you offer stepping systems for Arctic drilling conditions?

A: Yes. Our Arctic stepping systems are rated for -45°C continuous operation, with cold‑hardened seals, heated fluid reservoirs, low‑temperature steel, and water‑free pneumatics. These systems have been field‑proven on SJ Petro drilling rigs operating for Rosneft in Siberia.

Q8: What is the typical lead time for a new drilling rig with an integrated stepping system?

A: For a new ZJ series AC VFD rig with integrated stepping system, lead time is 8–12 months from order confirmation to FOB port shipment. Arctic‑rated stepping systems add 2–3 months for material testing and certification.

Q9: What training do you provide for stepping system operation?

A: Our standard rig supply includes on‑site training for drillers and maintenance crews on stepping system operation, emergency stop procedures, and basic troubleshooting. Training includes both classroom instruction and supervised practice moves on your pad. Extended training packages are available.

Q10: Can the stepping system be operated remotely?

A: Yes. The stepping system can be controlled from the driller's HMI in the control cabin or from a wireless remote pendant for external observation. Remote operation allows a single crew member to manage the walking sequence while others stand back at a safe distance.