Common Parts/Capscrew

Products & Range Coverage
A&S MACHINERY CO., LTD. delivers an extensive inventory of specialized high-strength capscrews and matching fasteners to support diverse heavy diesel engines, hydraulic systems, transmissions, and structural assembly requirements:
• Machine & Assembly Compatibility: Engineered for a broad range of Caterpillar equipment—including heavy diesel engines (e.g., CAT C15, C18, 3406, 3512), hydraulic pumps, transmissions, and swing bearings—our parts ensure exact thread tolerances, shank lengths, and strength grades (such as Grade 10.9 and 12.9) matching original factory designs for hex head capscrews to guarantee a perfect match.
• Complete Capscrews & Components: 1. Engine & Cylinder Block Capscrews: Cylinder head bolts, main bearing cap bolts, flywheel housing and crankshaft pulley capscrews; 2. Hydraulic Pump & Valve Capscrews: High-pressure impulse-resistant socket head capscrews, multi-way valve and motor connection bolts; 3. Powertrain & Structural Fasteners: Transmission flange specialty capscrews, axle housing and final drive high-strength fixing screws; 4. Matching Washers & Locking Hardware: High-strength quenched flat washers, thermal cycle-resistant Belleville disc springs, and high-temperature thread locking assemblies.
• OEM & Heavy-Duty Aftermarket: We offer certified original equipment manufacturer Caterpillar capscrews alongside rigorously tested heavy-duty aftermarket options manufactured via premium alloy steel hot-forging, precision thread rolling, and phosphating or Dacromet anti-corrosion treatments, delivering exceptional shear capacity and fatigue resistance at a cost-effective bulk procurement price point for global clients.

Supply Chain & Logistics
We maintain a robust operational infrastructure designed to support global machinery high-precision fastener procurement through direct supply channels, delivering reliable stock availability and rapid dispatch to build trust with international buyers.
• Massive SKU Inventory and Sorting: We maintain large-volume stock of thousands of inch and metric specifications, thread pitches, and strength grades of CAT specialty internal and external hex head capscrews. Utilizing barcode-enabled intelligent warehouse management and precision weighing sorting systems, we guarantee zero-error precise picking and direct dispatch upon order confirmation to eliminate equipment downtime caused by missing single specialty bolts leading to forced machine stoppages.
• Anti-Rust and Secure Heavy Packaging: We implement specialized industrial packaging standards for high-precision alloy steel capscrews, utilizing vapor corrosion inhibitor oil spraying, moisture-proof vacuum-sealed bags, thickened double-wall corrugated master cartons, and palletized wooden base fixation to ensure parts do not scatter, get damp, or rust during transcontinental ocean or air transit.
• Consolidated Sourcing: We support overseas clients by consolidating precision capscrews into precise bundled shipments alongside major overhaul components, such as engine overhaul kits, hydraulic pumps, and heavy undercarriage parts, maximizing container space utilization and significantly reducing international freight costs.

Engineering Solutions & Technical Support
Our technical framework focuses on resolving field-level operational challenges to eliminate equipment downtime, moving beyond simple parts distribution to deliver comprehensive engineering and service capabilities.
• Application-Specific Durability Solutions: We address common field issues in extreme working environments, such as high-load continuous-operation mining trucks and high-temperature high-humidity vibration-heavy jobsites, where engine high-temperature bolts suffer from thermal fatigue fracture and hydraulic system high-pressure flange socket head bolts experience frequent shear leaks. We also provide professional engineering upgrades, including Grade 12.9 ultra-high tensile strength alloy steel bolts, high-temperature anti-seize threaded fastening solutions, and fatigue-resistant elastic fastening combinations.
• Capscrew Troubleshooting and Torque Guidelines: We address common user concerns regarding joint fastening failures by providing professional diagnostic and replacement guidance. This includes instructions on how to determine whether bolt failure stems from insufficient preload causing alternating stress fatigue fracture or excessive torque causing plastic stretching, alongside emphasis on blind hole oil and debris cleanup and correct grease application prior to installing engine cylinder head and high-pressure hydraulic capscrews to ensure accurate preload maintenance.
• Expert Technical Support and Safety Guidelines: We provide technical documentation covering standard torque specifications, cross-pattern tightening sequences, and torque-plus-angle tightening procedures for all core Caterpillar assembly capscrews, preventing cylinder block warping or oil leaks caused by uneven tightening.

Call to Action & User Experience
Optimize your engine structural reliability and hydraulic joint security today by utilizing our interactive tools placed across strategic positions on our platform.
• Multi-Dimensional Intelligent Search and Specification Filtering: Benefit from advanced search functions that support fast product filtering by Caterpillar machine or engine model, including CAT C15 or 3406 units, capscrew head type (such as hex head versus socket head options), thread size and length specifications, or application area (such as cylinder heads, hydraulic pumps, and transmissions), to lock onto target products instantly.
• RFQ and Bulk Fastener Quotation: Access our fast-response interactive channels providing one-click bill of materials uploads for engine overhaul bolt lists to receive bundled quotations and heavy cargo freight estimates, fulfilling centralized procurement requirements for overseas mining sites, fleets, and repair shops.
• Consultation and Support: Utilize our around-the-clock professional technical support channels staffed by senior powertrain and fastener experts to assist overseas clients in verifying thread pitch and strength standards for legacy models or special Unified National Coarse and Unified National Fine threads, ensuring cross-border procurement runs error-free.