Case Study: Hydraulic Cylinder Coating Line, Shandong
Summary
A coating line for a hydraulic cylinder manufacturer in Linyi, Shandong, that produces around one million cylinders a year for construction machinery, port equipment, marine and energy applications. Long, heavy cylinder barrels are carried on a conveyor and hanging method that keep them stable over their full length, pass spray booths arranged in sequence so coverage builds evenly around the tube, and cure in an oven sized to the barrel lengths in production. Exhaust treatment is included, and the line runs as part of the client's regular production in 2026.
Project Background
The client, based in Linyi, Shandong, makes hydraulic cylinders, hoses and assemblies for construction machinery, port equipment, marine and energy applications, at a scale of around one million cylinders a year.
The Challenge
Cylinder barrels are long, heavy and round. They need even coverage around the full circumference and along the full length, and at the client’s volumes the line cannot slow down to handle each barrel by hand.
MUSI's Solution
MUSI arranged the line for long cylindrical parts: a conveyor and hanging method that keep barrels stable over their full length, spray booths set in sequence so coverage builds evenly around the tube, and curing sized to the barrel lengths in production.
Equipment Scope
- Pretreatment
- Conveyor for long cylindrical parts
- Spray booths in sequence with exhaust ducting
- Curing oven
- Exhaust treatment
Results
The line runs as part of the client’s regular cylinder production, coating barrels evenly along their full length at production volume.
Selection logic: why this configuration
Sequential booths with the barrel passing through in a fixed orientation were chosen over a single booth with rotation because barrels at this volume cannot be turned by hand and hanging them for rotation was not stable at their length. A conveyor and hanger designed for long cylindrical parts keeps barrels from swinging, which is what allows even film along the full length at production speed.
Scope of supply and key components
| Item | Specification | Notes |
|---|---|---|
| Pretreatment | For machined cylinder barrels | |
| Conveyor | For long cylindrical parts, stable hanging | |
| Spray booths | In sequence with exhaust ducting | Even coverage around the barrel |
| Curing oven | Sized to barrel length | |
| Exhaust treatment |
Key components
Key components are available from international brands, configurable per customer specification, so that spare parts can be sourced locally over the life of the line. Brand names below are the usual options for this type of equipment; the brands actually fitted are fixed in the contract specification.
| Component | Brands available on request |
|---|---|
| Automatic liquid guns, pumps and 2K proportioners | Graco ProMix 2KS, Sames Airmix, WAGNER AirCoat, Nordson, Binks (Carlisle Fluid Technologies) |
| Oven and dryer gas burners | Riello RS series, Weishaupt monarch WM-G, Baltur TBG, Honeywell Maxon OVENPAK, Eclipse |
| PLC and HMI | Siemens SIMATIC S7-1500, Mitsubishi Electric MELSEC iQ-R, Schneider Electric Modicon, OMRON NX, Rockwell Automation Allen-Bradley |
| Variable-frequency drives | ABB ACS580, Siemens SINAMICS G120, Danfoss VLT, Schneider Electric Altivar, Yaskawa, Mitsubishi Electric |
| Conveyor gear motors | SEW-EURODRIVE, NORD DRIVESYSTEMS, Bonfiglioli, Siemens, Sumitomo Drive Technologies |
| Booth ceiling and intake filter media | Freudenberg Viledon, AAF SureStop, Camfil, MANN+HUMMEL |
| Pretreatment pumps and chemistry | Grundfos CR, KSB Etanorm, Xylem; Henkel BONDERITE, Chemetall Gardobond, PPG Zircobond, Nippon Paint |
| Sensors and temperature controllers | SICK, Pepperl+Fuchs, OMRON E5CC, Honeywell UDC, Yokogawa UT, ifm, KEYENCE |
Not included in the scope of supply
- Civil works, foundations and pits
- Building services up to the battery limit: power supply, gas, compressed air, water and drainage
- Local permits, emission approvals and third-party inspections
- Paint or powder supply, unless stated in the contract
Services included with every line: engineering design, manufacturing, shipping documentation, installation supervision, commissioning, operator training, warranty and spare parts.
Typical programme
The durations below are typical for equipment of this class and are given for planning; they are not the recorded schedule of this project. A complete line usually runs 90–180 days from contract to acceptance, a single unit 30–60 days.
| Stage | Typical duration | What happens |
|---|---|---|
| Site survey and workpiece review | 5–10 days | Remote review of drawings and photos, or an engineer visit |
| Layout and detail design | 15–30 days | Layout drawing, utilities list and specification sign-off |
| Manufacturing | 45–90 days | Booths, ovens, conveyor, pretreatment and controls built and pre-assembled at the works |
| Shipping | 20–45 days | Sea freight; equipment shipped in sections for on-site assembly |
| Installation | 15–40 days | MUSI supervision with the client's installation crew or MUSI crew |
| Commissioning, training and acceptance | 7–15 days | Trial runs on the client's parts, operator training, acceptance record |
Applicability and limits
The layout applies to round barrels and assemblies within the hanger length and weight; very long cylinders for cranes or marine use may need a floor-mounted handling system. Machined rod surfaces are masked according to the client's drawing, which sets part of the cycle time.
Results shown in this case study reflect the stated operating conditions and should not be interpreted as guaranteed performance under different feed, production, environmental, or site conditions.
After-sales and spare parts
Warranty on a MUSI coating line runs from acceptance: 12 months on the complete line excluding consumables, 36 months on critical components such as motors, drives and the PLC, and 60 months on structural parts such as steel structure, ducting and oven bodies. Failures within warranty, excluding misuse, are repaired free of charge.
Support starts remotely: the service line is staffed around the clock, a preliminary diagnosis with recommendations is given within 2 hours, and where a site visit is needed an engineer reaches any major city within 72 hours. A spare-parts inventory is held at the Changzhou headquarters with same-day shipping, and customers can keep a dedicated parts stock at MUSI for emergencies. Details are on the after-sales service page.
FAQ
How are hydraulic cylinder barrels coated evenly? By passing them through spray booths arranged in sequence so each booth adds coverage from a different angle, with the barrel held stable on a hanger designed for long round parts.
How is the chrome rod protected from paint? Rod and port faces are masked per the client's drawing before the parts enter the line; masking and unmasking are part of the loading stations.
What line speed is possible at one million cylinders a year? The conveyor and oven were sized to the client's annual volume and barrel lengths; the speed is set by the cure time of the longest barrel.
Why not rotate the barrels in one booth? At these lengths and volumes hanging for rotation was not stable; sequential booths give the same coverage without turning the part.
Is the line in production? Yes, coating barrels along their full length at the client's production volume.
Next step: a configuration proposal for a similar line
If your parts, volumes or plant conditions are close to this project, MUSI can return a line configuration and layout proposal. To prepare it we need four things:
- Photos and dimensions of the workpieces, with weight and material
- Required output (pieces per hour or per day, and shifts)
- Number of colours and how often colour changes are needed
- Available floor space and ceiling height, with the utilities on site
Message us on WhatsApp with these details, or use the quotation form.
Published 2026-09-26 · Updated 2026-09-30 · Last technical review: 2026-09-30
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Provided by Lin Cong, Technical Director, MUSI Technology