A hydraulic cylinder with the same bore and stroke is not automatically a replacement for a German machine builder. Confirm the interfaces, rod, load, pressure and operating conditions before the manufacturer and customer approve it. We can coordinate agreed German sample reception, document handover and commercial follow-up, alongside entity and tax arrangements. Application design and technical acceptance remain with the responsible engineers.
An enquiry may mean build-to-print supply, reproducing an authorised sample, or qualifying an alternative source for an installed machine. Identify which one before offering a firm scope. A nameplate photograph alone rarely settles every connection, seal or acceptance requirement.
Define the replacement deliverable
Request an authorised drawing revision and application information. Confirm permission to share customer designs; photographs support identification but do not replace a manufacturing specification. Measurement, dismantling and engineering approval need their own arrangements.
Create a missing-information list with an owner and its effect on price or suitability. You can discuss a conditional budget while engineering details remain open. Do not describe that budget as an approved drop-in replacement.
| Input | Technical decision | Commercial output |
|---|---|---|
| Bore, rod, stroke and closed dimensions | Area, space and load suitability | Identified candidate configuration |
| Mounting, connection dimensions and rod end | Interfaces, tolerances and side-load conditions | Revision-controlled interface drawing |
| Pressure, flow, cycle, fluid and temperature | Seals, speed, cushioning and load conditions | Manufacturer response and limitations |
| Failure history and acceptance request | Whether the cause is understood | Trial scope, ownership and fees |
Separate extension from retraction
Parker’s HMI catalogue gives the theoretical relationship F(kN)=P(bar)×A(mm²)/10000 on printed page 21, PDF page 23. Effective rod-side area excludes the rod cross-section. This is an arithmetic basis, not proof of an installed cylinder’s performance.
For an invented example, assume a 63mm bore,36mm rod and 160bar applied separately to either side, with opposite-side backpressure ignored. Piston area is about 3117.25mm² and annular area 2099.37mm²: theoretical extension is 49.88kN and retraction 33.59kN. These are assumed dimensions, not our test results or an offered product rating.
Effective area changes with the direction of force
When purchasing asks for 40kN, establish direction, location and whether the request is continuous or peak. This example exceeding 40kN in extension would not satisfy the same theoretical retraction demand. Neither number establishes a design margin. The application owner must approve the actual requirements.
Check speed and installation conditions
With a further assumed effective flow of 20L/min and no leakage, v=Q/A gives approximately 107mm/s extension and 159mm/s retraction. This is a quotation consistency check, not an instruction to change a machine’s pressure or flow. Real valves, lines, controls and backpressure need review.
Changing rod size affects annular area as well as load-related checks. Do not discuss only nominal force. Obtain the supplier’s rod and stroke assessment against the specified mounting and duty; Parker treats these checks separately from its theoretical-force table.
Make the sample evaluation traceable
Name the receiving contact, technical installer, test provider and approval owner before sending the sample. Agreed German receipt can record packaging, quantity and visible identity. It does not include a pressure-test certificate, commissioning or an engineering release by implication.
Keep the sample ID, drawing revision, operating conditions, test method and agreed acceptance criteria together. An issue recorded on video is evidence to investigate, not a diagnosis for a sales representative to invent. Where external testing is required, agree competence, scope, cost and the commissioning party first.
| Stage | Record | Responsible output |
|---|---|---|
| Pre-dispatch | Approved candidate and missing items | Manufacturer technical response |
| Receipt | Quantity, identity and damage observations | Agreed receiving record |
| Evaluation | Method, conditions and findings | Customer/competent technical assessment |
| Exception | Affected revision and evidence | Written disposition and cost authority |
Carry the approved version into supply
Link the approved drawing, material/seal configuration, interfaces, packaging and marking to the purchase line. One accepted sample does not approve the whole range. Changes require the contractually agreed review rather than a silent substitution.
Separate sample price, transport, test work, returns, production pricing and payment. Establish the stock owner, seller and importer before arranging local invoices or VAT. A German receiving address is not evidence of model-specific repair capability or supplier qualification.
Arrange German commercial support
Send the shareable drawing, candidate model, customer requirement, current order stage and local assignment. We can discuss German sample reception, meetings, document transmission and authorised commercial follow-up, plus company and VAT arrangements.
Agree storage conditions, confidentiality, price authority, fees and exception handling. Engineering decisions and acceptance stay with the appointed technical parties. Discuss German hydraulic-cylinder support →
Sources and checks
Checked: 2026-10-29