The questions we are asked most often.

How long does a hydraulic cylinder rebuild take?

Standard rebuild turnaround is 3–5 working days from receipt at the workshop. Turnaround depends on component condition — if additional machining, rod replacement, or part sourcing is required, we advise before proceeding. Emergency turnaround is available for retained customers.

What is the difference between cylinder honing and cylinder rebuild?

Honing is a single process — it resizes and refinishes the bore to correct dimensional tolerance and surface finish. Rebuild is a complete cycle: strip, inspect, hone the bore, restore or replace the rod, machine worn components, fit new seals, reassemble, and pressure-test. A honing-only job is faster and lower cost; rebuild is specified when multiple components need attention.

What bore sizes can you hone?

Internal diameter range 50mm to 900mm. Maximum bore length 8,000mm for closed cylinders, 16,000mm for open-bore cylinders. Dimensional tolerance ±2 microns.

Can you cut seals for obsolete or non-standard sizes?

Yes. Santoo cuts seals from stock material to any profile and dimension. Provide a drawing, a sample, or a dimensional description. We manufacture from the first piece.

What pressure does your test bench reach?

Cylinder test bench: 700 bar working pressure, 700 litre tank capacity, SCADA-monitored. Pump test bench: open and closed loop, maximum displacement 350 cm³/rev. Test reports are issued per unit and retained on file.

Which elastomer should I specify for sour gas service?

FKM (fluorocarbon rubber) or HNBR (hydrogenated nitrile) are the standard choices for sour gas environments. FKM offers better resistance to H₂S and aromatic hydrocarbons at elevated temperatures. HNBR is preferred where mechanical strength under dynamic conditions is the primary requirement. For the most aggressive sour service, FFKM (perfluoroelastomer) is specified. Material selection should also account for the specific gas composition, temperature, and pressure. Contact our engineering team with your service conditions for a specific recommendation.

Do you supply seal kits for standard cylinder platforms?

Yes. Santoo supplies OEM-equivalent seal kits for common hydraulic cylinder platforms used in construction, mining, marine, and process industries. Non-standard kits are assembled from stock material or cut to drawing.

What certifications cover your elastomer compounds?

ISO 9001:2015 covers manufacturing quality system. API 6A covers compounds for wellhead and BOP service. NSF covers compounds for potable water and food-contact applications. WRAS covers elastomers for drinking water service. Material certificates and batch traceability are supplied with orders where certification is specified.

Can you collect and return cylinders?

Yes. Collection and return logistics are available for retained customers and for large or heavy equipment that cannot easily be transported without specialist handling. Contact the workshop to arrange.

What does a documented work-order package include?

Receipt condition notes, dimensional measurements pre- and post-operation, details of all work performed, seal compound specifications, pressure test results with SCADA data, and sign-off by the supervising engineer. The package is issued with the unit and a copy is retained on file.

Question not answered here? Ask the engineering team directly.