Heavy-Duty Main Boom Extension Cylinder (815mm Stroke)

The main boom extension cylinder is a mission-critical component in any aerial work platform, truck-mounted crane, or elevated access vehicle. Operating under constant high-cycle loading at height, these cylinders must deliver smooth, repeatable extension with zero positional drift — and in the UK construction, utilities, and telecoms sectors, the margin for mechanical failure is simply zero. Our HCYY11112009 is purpose-built to meet and exceed those demands, combining precision-honed bore geometry, multi-layer sealing technology, and a forged carbon-steel structure that handles 23 MPa working pressure as a baseline — not a ceiling.

With an 815 mm stroke and an installation distance of 1,433 mm, this boom extension cylinder occupies a structural sweet spot that suits mid-to-large platform configurations. Whether you’re specifying a replacement cylinder for an ageing fleet or sourcing components for a new-build aerial work vehicle destined for the UK hire market, the HCYY11112009 delivers the dimensional accuracy and burst-pressure headroom that fleet operators and OEM engineers expect.

How the Main Boom Extension Cylinder Works

At its core, the main boom extension cylinder is a double-acting hydraulic linear actuator. Pressurised hydraulic fluid — typically ISO VG 46 mineral oil — enters via the port on the cap end, pushing the piston and rod assembly outward to extend the boom section. Reversing the oil flow to the rod-end port retracts the cylinder with equal controlled force. The 23 MPa working pressure drives a substantial thrust force through the Φ110 mm bore, while the Φ75 mm rod diameter ensures the column strength needed to resist buckling under compressive loads at full 815 mm extension — a geometry validated by finite element analysis across the design envelope.

The cylinder barrel is manufactured from precision cold-drawn seamless steel tube, then honed to an Ra 0.2–0.4 µm internal finish. The piston rod is ground from 45# high-carbon steel, then hard-chrome plated to 0.025–0.05 mm depth and polished to mirror finish — a process that dramatically reduces seal wear and prevents the micro-pitting that shortens service life in outdoor, dust-exposed environments. All sealing faces undergo 100% pressure-decay testing before assembly sign-off.

Technical Specifications

Full factory datasheet parameters — HCYY11112009 Main Boom Extension Cylinder

Why UK Engineers Choose This Boom Cylinder

Specifying the right boom extension cylinder for aerial work vehicles operating in the UK means accounting for variable ambient temperatures, the high duty-cycles common in hire-fleet operations, and the strict load-test regimes demanded by UK LOLER inspection standards. The HCYY11112009 is designed with all of these realities in mind — not as afterthoughts, but as core engineering constraints that shaped every material choice and dimensional tolerance in the design.

Application Scenarios

The HCYY11112009 main boom extension cylinder serves a broad range of aerial and lifting applications across UK industry. Its 100 kg weight and 815 mm stroke place it firmly in the mid-frame segment, where it handles some of the most demanding duty profiles in the market — continuous hire-fleet cycles, high-throughput maintenance operations, and mission-critical utility access work where downtime costs are simply unacceptable.

Cylinder Series for Aerial Work Vehicles

The HCYY11112009 is part of a comprehensive family of boom and lift cylinders developed specifically for aerial work vehicle OEMs and operators. Whether you require a slewing cylinder, a luffing cylinder, or a secondary extension stage, the full series covers bore diameters from Φ40 mm through to Φ200 mm, strokes from 200 mm to over 2,000 mm, and working pressures up to 28 MPa. Two popular sister products from this programme include:

Customer Success: UK Aerial Platform Fleet Operator

Midlands-based powered access hire company | 120-unit fleet renewal programme

Factory Capabilities & Custom Engineering

Our manufacturing facility covers 28,000 m² of production floor space and operates 14 CNC honing lines capable of holding bore tolerances to H8 class across the full bore range. Bore diameter, rod diameter, stroke, mounting geometry, port size and thread standard, seal compound, and coating specification are all available as configurable parameters — we do not operate a catalogue-only model. If you’re developing a new aerial work vehicle for the UK market or rebuilding an existing platform to a modified specification, our engineering team can work from your SolidWorks, AutoCAD, or PDF drawings and return a dimensional and pressure confirmation within 72 hours.

Frequently Asked Questions

Common questions from UK aerial platform engineers, fleet managers, and OEM procurement teams