Our Air End Rebuilding Process — From Disassembly to Delivery
At Khan Contractor, our air end rebuilding process follows a strict, systematic approach to ensure every rebuilt unit meets the highest standards of performance and reliability.
Receive and Log the Air End Rebuidling
We receive the air end at our facility in Karachi, log it into our system, and record all relevant details including the brand, model, serial number, and reported symptoms.
Complete Disassembly
Our certified technicians carefully disassemble the air end in a clean environment, removing all external fittings, bearing housings, rotors, seals, and gears using proper tooling to avoid component damage.
Detailed Inspection and Diagnosis
Each disassembled component is meticulously inspected for wear, corrosion, damage, and dimensional accuracy. We use precision measuring instruments to check rotor profiles, bearing journals, and housing tolerances. A comprehensive diagnostic report is prepared at this stage.
Cleaning and Surface Preparation
All reusable parts — including the main casing and rotor bodies — are cleaned using industrial methods to remove oil deposits, carbon buildup, and surface contamination, ensuring perfect surface conditions for reassembly.
Replacement of Worn Components
All worn or out-of-tolerance components are replaced using OEM-grade rebuild kit parts, including:
Precision ball and roller bearings
Shaft seals and lip seals
Gaskets and O-rings
Timing gears (if required)
Inlet valve seals
Precision Reassembly
The air end is reassembled with careful attention to bearing preload settings, rotor clearances, and torque specifications — exactly as specified in the original manufacturer's technical documentation.
Performance Testing
Once reassembled, the air end undergoes bench testing and performance verification to confirm it meets pressure, flow, and efficiency targets before it is returned to the customer.
Delivery and Reinstallation Support
We deliver the rebuilt air end to your facility. Our team is also available to assist with reinstallation and commissioning on request, ensuring a smooth return to full operation.
Professional Air End Rebuilding Services in Karachi
Air end rebuilding is the process of overhauling the compression element of a new screw air compressor by replacing worn internal components — including bearings, shaft seals, gaskets, and O-rings — to restore the unit to its original operating efficiency. Khan Contractor provides professional air end rebuilding services in Karachi, Pakistan, for all major compressor brands including Atlas Copco, Ingersoll Rand, Kaeser, Sullair, and CompAir. The service is a cost-effective alternative to buying a new air end, typically saving businesses 40% to 60% on replacement costs while delivering factory-level performance and a warranty on all replaced components.
What Is an Air End in a Screw Air Compressor?
The air end (also called the compression element) is the core unit inside a screw air compressor responsible for generating screw compressed air end. It houses two precision-machined helical rotors — a male rotor and a female rotor — that intermesh and rotate at high speed inside a sealed casing. As air enters through the inlet valve, the rotating rotors trap and progressively compress the air, pushing it out at the desired pressure.
Because the air end operates under extreme mechanical stress, high temperatures, and continuous rotation, its internal components — particularly the bearings, seals, timing gears, and rotor coatings — are subject to wear over time. When these components degrade, the entire screw compressor air end suffers: energy consumption rises, output pressure drops, and the risk of sudden failure increases significantly.
Understanding the condition of your compressor air end is therefore not just a maintenance matter — it is a direct factor in your operational efficiency and profitability.
One of the most common questions we receive is: "Should I rebuild my air end or buy a new one?" Here's a straight comparison:
Air End Rebuilding vs. Buying a New Air End — Cost Comparison
What's Included in Our Air End Rebuild Kit?
Our air end rebuilding service uses high-quality rebuild kits that include all the components needed to fully restore the compression element. A standard kit includes:
Main Bearings — Precision ball and roller bearings for both the male and female rotors.
Shaft Seals — Lip seals and mechanical seals to eliminate oil leakage.
Gasket Set — Complete gasket kit for all mating surfaces.
O-Ring Set — Full set of O-rings for all ports and covers.
Timing Gears (where applicable) — For brands requiring gear-driven rotor synchronization.
Bearing Retaining Rings and Circlips.
Oil Inlet Seals.
All components are sourced from trusted suppliers and are compatible with OEM specifications, ensuring long-lasting performance after the rebuild.
Unlike general mechanical workshops, Khan Contractor focuses exclusively on screw air compressors — making air end rebuilding one of our core specializations backed by dedicated tools, trained technicians, and deep technical knowledge. Every rebuild uses OEM-grade bearings, seals, and gaskets — no shortcuts, no substandard parts. Before any work begins, we provide a full written diagnosis and cost estimate so you stay in control of every decision. Most rebuilds are completed within 3 to 7 working days, minimizing costly downtime for your operations.
All rebuilt air ends carry a warranty on replaced components, and our technicians are available for onsite diagnostics across Karachi and surrounding areas. Beyond air end rebuilding, we also offer new and used air compressor sales, spare parts, air compressor maintenance contracts, and rental air compressors — making Khan Contractor your single point of contact for all compressed air needs in Pakistan.
Why Karachi's Industries Trust Khan Contractor for Air End Rebuilding
Our recommendation: If your rotor profiles are in good condition and the primary wear is in the bearings and seals, rebuilding is almost always the smarter choice. Our technicians will give you an honest assessment after inspection — so you make the right decision for your operation.
FAQ’s About Air End Rebuilding
How long does an air end rebuilding service take?
Typically, a standard air end rebuild takes 3 to 7 working days, depending on the size, brand, and availability of parts. We will give you a specific timeline after the initial inspection.
How much does air end rebuilding cost in Pakistan?
The cost depends on the brand, size (kW rating), and the extent of internal wear. However, rebuilding is generally 40–60% less expensive than purchasing a new air end. Contact us for a free quote.
Will my compressor perform like new after the air end is rebuilt?
Yes — when rebuilding is performed professionally with OEM-grade parts and correct compressor air end assembly procedures, the air end will perform at or near its original factory efficiency levels. Many customers report improved pressure consistency and lower energy consumption after a professional rebuild.
Get in touch
Plot#7, Sector 12A North Karachi Industrial Area, Khi
Phone
+92-333-3435693
+92-21-36941527
Fill out the form below and our team will get back to you within 24 hours with a free assessment and cost estimate for your air end rebuilding service.
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Khan Contractor
Need industrial air compressors in Karachi? Khan Contractor supplies new & used compressors, genuine parts, rentals, and maintenance services.
info@khancontractor.com
+92-333-3435693
+92-21-36941527
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Plot#7, Sector 12A North Karachi Industrial Area, Khi