Medium duty oil rigs

Technical Specifications

Here's a detailed look at key technical parameters across our medium duty product range. All specifications are customizable for your specific depth, environmental, and power requirements.

Parameter	XJ250 (Entry Medium)	XJ450 (Mid-Range)	XJ550 (Upper Medium)	ZJ40 (Heavy Medium)
Drilling Depth (4‑1/2″ DP)	1,000–1,500 m	1,500 m	2,000 m	4,000 m
Workover Depth (2‑7/8″ DP)	3,500 m	4,500 m	7,000 m	10,000 m
Max Static Hook Load	675 kN (151,700 lbs)	1,125 kN	1,350 kN	2,250 kN (505,800 lbs)
Rated Hook Load	400 kN (90,000 lbs)	800 kN	1,000 kN	2,250 kN
Installed Power	235–350 HP	450–600 HP	550–650 HP	1,260 HP (dual engines)
Engine	Cat C9	—	Cat C18	Dual Cat C18
Transmission	Allison 4700	—	—	Allison M6620AR (dual)
Traveling System	3×4 (Φ22mm wireline)	4×5	4×5	6×5 (Φ32mm wireline)
Carrier Drive Type	6×4 / 10×8	10×8	10×8	14×10
Mast Height	31 m	34 m	34 m	—
Floor Height	3.3 m	3.7 m	4.5 m	—
Max Travel Speed	60 km/h	—	—	45 km/h
Overall Dimensions (L×W×H)	18.5×2.9×4.2 m	—	—	22.2×3.1×3 m
Gross Vehicle Weight	50,000 kg	—	—	76,000 kg
API Compliance	Q1, 4F, 7K, 8C	Q1, 4F, 7K, 8C	Q1, 4F, 7K, 8C	Q1, 4F, 7K, 8C
Environmental Range	–30°C to +55°C	–30°C to +55°C	–30°C to +55°C	–45°C to +55°C

Product Types – Our Medium Duty Rig Lineup

Product Series	Type	Key Features	Best For
XJ250 (SXJ250)	Self-propelled workover/drilling	Cat C9 engine, Allison 4700, 3,500m workover depth	Entry-level medium duty, workover-dominant operations
XJ350 (SXJ350)	Self-propelled workover/drilling	4,000m workover depth	Mid-range workover with drilling capability
XJ450 (SXJ450)	Self-propelled workover/drilling	4,500m workover, 1,500m drilling depth	Balanced dual-purpose operations
XJ550 (SXJ550)	Self-propelled workover/drilling	1,350 kN max hook load, 5,800m workover depth	Heavy workover, light-to-medium drilling
XJ650 (SXJ650)	Self-propelled workover/drilling	Cat C18 engine, 7,000m workover, 2,000m drilling	Upper-medium capacity, popular for multi-role applications
XJ1000 / XJ1200	Self-propelled workover	1,800–2,250 kN hook load, 8,000–9,000m workover depth	Heavy-duty workover bordering on full drilling capacity
ZJ40 Truck-Mounted	Mobile drilling rig	Dual Cat C18 engines, 4,000m drilling depth, 10,000m workover	Heavy medium drilling, crossover workover capability

The XJ series covers the full spectrum from XJ150 (entry-level) through XJ1200, with maximum static load ranging from 300 kN to 2,250 kN and installed power from 235 HP to 1,300 HP .

Application Fields – Where Medium Duty Rigs Excel

1. Mature Field Infill Drilling

Existing oilfields don't stop producing — but they do need ongoing infill drilling to maintain output. The wells are typically medium depth (1,500–3,000 meters), the pad locations are established, and access roads are already in place. A heavy-duty rig is overkill. A medium duty rig is just right.

How SJ Petro helps: Our XJ series rigs arrive on location under their own power, drill the infill well, workover any nearby production wells that need attention, and move to the next pad — all without calling in a crane or a transport crew.

2. Shallow-to-Medium Depth Development Drilling

For new field developments with target depths up to 3,000–4,000 meters, a 2,000 HP super-rig is expensive and unnecessary. Our ZJ40 truck-mounted rig drills to 4,000 meters with 2,250 kN hook load — more than enough for most medium-depth programs — at a fraction of the capital cost of a larger rig .

3. Workover and Well Intervention (The Core Mission)

Let’s be honest. Most medium duty rigs spend the majority of their operating life doing workover — not drilling. Paraffin scraping, fishing jobs, pump replacements, stimulation treatments, sidetracking. You need a rig that’s fast to mobilize, quick to rig-up, and efficient on location.

How SJ Petro helps: The entire XJ series is designed first as a workover rig, with drilling capability added as a secondary function. Fast travel speeds (up to 60 km/h), rapid mast erection, and self-contained power systems mean you're working on the well — not waiting for the rig to get there.

4. Remote & Road-Limited Locations

Not every wellsite has a highway leading to it. Jungle tracks, mountain roads, arctic tundra — conventional rig transport can be impossible.

How SJ Petro helps: Our self-propelled rigs require only road access (no oversized transport permits). For truly remote locations, we offer helicopter-liftable module configurations. And our arctic-spec rigs have been deployed in Russian oilfields at –45°C.

5. Offshore Platform Workover

Platform deck space is limited. Bringing a full-size jack-up rig for a workover can be prohibitively expensive. Compact, self-contained medium duty modules can be mobilized for the job and demobilized afterward — leaving the platform for production equipment.

How SJ Petro helps: Our offshore-capable medium duty modules are marine-grade with corrosion-resistant coatings, and we can supply ABS, DNV, or CCS certification upon request. Integrated skidding systems allow movement between well slots.

6. Shallow-Water Jack-Up Rigs

Jack-up rigs operating in water depths up to 120 meters (400 feet) are well-suited for medium duty drilling packages . These rigs need drilling equipment that fits within the platform's weight and space constraints while still delivering the necessary depth capacity.

How SJ Petro helps: Our ZJ series rigs can be configured as offshore jack-up drilling modules, with hook loads up to 2,250 kN and drilling depths up to 4,000 meters — fully marine-certified.

Why Choose SJ PETROLEUM MACHINERY for Medium Duty Rigs?

I’ve worked in this industry long enough to know that buyers don't just want a spec sheet. They want to know: Will this rig work when I need it? Will the company stand behind it? Am I overpaying?

Here’s the case for SJ Petro.

1. We’re a Sinopec subsidiary. As a wholly-owned subsidiary of Sinopec Oilfield Equipment Corporation, our rigs are tested and validated in Sinopec's own oilfields (Shengli, Jiangsu, Tarim) before export. You're not our beta tester.

2. Over 80 years of continuous manufacturing. We started building drilling equipment in 1941. Our product lines now cover 200+ models across 12 series, including drilling rigs, workover equipment, cementing units, fracturing equipment, offshore drilling and production systems, and high-pressure fluid controls .

3. Proven global track record. Our equipment has been exported to more than 30 countries across North America, Russia, Central Asia, the Middle East, Southeast Asia, and Africa, with 3,000+ international trade transactions completed. The XJ650 rig alone is highly popular among users across South America, Western Africa, and the Middle East .

4. Field-proven power trains. Caterpillar engines. Allison transmissions. KOBELT disc brake systems. We use components that your mechanics already know how to maintain — and that parts suppliers stock worldwide.

5. Complete IP ownership. Our rig designs and control systems are自主研发 (independent R&D) with full intellectual property rights. No third-party licensing fees. No technology transfer restrictions. No vendor lock-in.

6. Cost‑effective without cutting corners. We typically deliver medium duty rigs at 30–40% lower upfront cost than comparable Western brands — not because we compromise on quality, but because we control our own manufacturing, maintain lean operations, and don't charge a brand premium.

7. Full compliance for international tenders. API Q1, 4F, 7K, 8C certified. ISO 9001 and HSE certified. Offshore certifications (ABS, DNV, CCS) available on request. We meet the requirements that procurement teams look for.

8. True customization. Not every 3,000-meter well is the same. Your formation, your climate, your existing support equipment — we adapt the rig to fit. Custom mast heights, power configurations, driller control layouts, and optional equipment packages are all available.

9. Global after-sales support. Onsite commissioning. Remote diagnostics. Spare parts stocking. Field service engineers ready to deploy worldwide. Driller training in your language.

Frequently Asked Questions (FAQ)

Q1: What is the typical depth rating for a medium duty oil rig?

Medium duty rigs are generally rated for drilling depths of roughly 4,000 to 10,000 feet (1,200 to 3,000 meters) with 4-1/2″ drill pipe, though some models (like our ZJ40) can reach 4,000 meters. For workover operations, the same rigs can handle much greater depths — our XJ series reaches workover depths up to 9,000 meters .

Q2: How much horsepower does a medium duty rig typically have?

Installed power typically ranges from 500 HP to 1,300 HP. Light-duty rigs top out around 500–700 HP. Heavy-duty rigs start above 1,500 HP. Our XJ series covers the medium range from 235 HP (entry-level) up to 1,300 HP (upper-medium) .

Q3: Can your medium duty rigs perform both drilling and workover operations?

Yes — specifically our XJ series. These are workover rigs with full drilling capability when equipped with a rotary table, swivel, and drilling tools. They can serve as mobile drilling rigs for medium and shallow wells . The XJ650, for example, reaches 2,000 meters drilling depth and 7,000 meters workover depth .

Q4: Are your medium duty rigs API certified?

Yes. Our drilling rigs are designed and manufactured in accordance with API Spec Q1 (Quality Management), API 4F (Drilling and Well Servicing Structures), API 7K (Drilling Equipment), and API 8C (Hoisting Equipment) . For offshore applications, we can supply ABS, DNV, or CCS classification upon request.

Q5: What engines do you use, and are parts available globally?

We use Caterpillar diesel engines (C9, C18, and dual-C18 configurations) paired with Allison automatic transmissions. These are globally available components with established parts and service networks in every major oil-producing region.

Q6: Can your rigs operate in extreme temperatures?

Yes. Standard operating range is –20°C to +55°C. Cold-weather (arctic) packages extend operation down to –45°C (storage down to –60°C) — proven in Russian oilfield deployments. Desert packages include enhanced cooling, sealed electronics, and dust-proof filtration for +55°C ambient conditions.

Q7: What's the rig‑up time for your XJ series medium duty rigs?

Because the XJ series rigs are self-propelled and self-contained, typical rig‑up time is 1–3 days from arrival on location to spudding. Mast erection is hydraulically assisted. Conventional rigs of similar capacity often require 2–4 weeks for rig-up.

Q8: What's your typical lead time for a medium duty rig?

• XJ series (XJ250 through XJ1200): 3–5 months from order confirmation

• ZJ40 truck-mounted rig: 4–6 months

• Custom configurations (special climate, offshore certification): 5–8 months

• Expedited options available for standard configurations — contact our sales team for current lead times

Q9: Do you provide operator training?

Yes. Training packages include classroom instruction, on-site commissioning and hands-on coaching during the first week of operation, maintenance and troubleshooting courses for your mechanics, and remote refresher training via video. All documentation is provided in English (or your preferred language) with detailed technical diagrams.

Q10: What warranty do you offer?

Standard warranty: 12 months from commissioning (or 18 months from shipment, whichever comes first). Extended warranty options available up to 36 months. Spare parts kits can be included in the initial purchase.

Q11: Can I visit your factory to inspect my rig before shipment?

Absolutely. Our manufacturing facility in Jingzhou, Hubei Province is open for customer inspections. We conduct factory acceptance tests (FAT) with customer representatives present. If travel isn't feasible, we offer live video inspections and third‑party inspection coordination (BV, SGS, DNV, etc.).