Two quotes for hydraulic cylinders can only be compared if they describe the same supply. It sounds obvious, but in practice it is not: for the same bore, stroke and declared standard, the price may include or exclude the testing of each individual piece, state or omit the material and treatment of the rod, make delivery times binding or leave them indicative, and guarantee or not the availability of spare parts over the years. Before asking which offer costs less, the buyer must ask whether the offers cover the same type of supply. This article proposes the grid for bringing quotes back to the same basis: unambiguous configuration, compliance with the standard, testing, declared materials, documentation, conditions over time. Only after this step does the price difference become information that can be interpreted, including in terms of total cost of ownership (TCO).
Why price alone compares nothing
A cylinder defined by series, bore and stroke looks like an unambiguous object, and it tempts you to read two quotes as two prices for the same thing. In reality the price pays for a scope of supply, and that scope is not standardized: each manufacturer decides what to include in the price (testing, technical documentation, options), what to declare explicitly (materials, seals, dimensional compliance) and what to guarantee over time (spare parts, handling of urgent requests). None of these items appears in the quote, but all of them determine its meaning. The operational point is neither to distrust the lowest offer nor to reward the highest on principle: it is to demand that the items of the scope be explicit in both offers, because what is not declared cannot be compared and, on delivery, cannot even be disputed. The first requirement lies upstream, in the request for quotation: a configuration specified unambiguously (series, bore, stroke, type of mounting, options such as sensors or treatments, with catalogue codes). A quote issued on an incomplete specification leaves the choice of the missing items to the supplier, and each supplier will fill them in its own way: from that point on, the offers describe different objects.
Testing: included or not, on how many pieces, with what records
Testing is the item that most often makes two apparently identical prices impossible to compare. There are three questions to ask: is testing included in the price? Does it cover 100% of the pieces or a sample? At what pressure and with what recording of the results? The standard reference is acceptance testing to ISO 10100, with a pressure test at 1.5 times the nominal pressure of the series. A cylinder tested individually on the bench, with recorded and traceable data, has demonstrated integrity and leak-tightness before shipment; a cylinder checked on a sample basis, or not checked at all, has the same apparent price but not the same content. What 100% testing involves in practice, and which defects it catches before they reach the field, is described in the article dedicated to hydraulic cylinder testing.
Materials, seals and documentation: declared beats implied
The quote must state what the cylinder is made of in the components that determine its service life: rod material and treatment (for example chrome-plated CK45 steel; for aggressive environments there are options with a corrosion-resistant Nikrom or stainless steel rod, up to the version with a nickel-plated cylinder and stainless steel rod for the most severe conditions) and type of seals. The buyer does not need to judge the metallurgy: the data need to be written down, because two offers that are silent on these components can be neither compared with each other nor checked on delivery. The same criterion applies to documentation: the complete datasheet, with declared operating and test pressures, and the 2D/3D CAD models for integration into design drawings are part of the supply, not a courtesy. A supplier that makes its technical department available as early as the quotation stage is taking on in advance a cost that would otherwise fall on the buyer.
Time: delivery, urgent requests, continuity of supply
The last dimension of the scope concerns not the piece but the service around it. Three elements should be read in the quote: the delivery date (binding or indicative?); the existence of a channel for urgent requests, with defined times, because when a cylinder stops a line the damage is measured in resupply time, and knowing in advance whether the supplier has a procedure for urgent orders (for example supply within 48 hours) is worth more than any discount; the continuity of spare parts supply over the years, which ISO compliance structurally facilitates. An offer with clearly specified times and a defined recovery channel contains a service that an offer without these clauses does not.
From comparability to total cost of ownership (TCO)
Once the offers have been brought back to the same basis, the price differences become readable: what one quote includes and the other does not has an identifiable value, and the comparison stops being a comparison between numbers and becomes a comparison between supplies. This is where the reasoning on total cost of ownership comes in: why a lower purchase price can translate into a higher overall cost in terms of downtime, spare parts and service life is the subject of the article on the paradox of the cheap cylinder. The methodological point of this article is the premise: TCO can only be assessed on comparable offers. Applying it to quotes that describe different supplies produces conclusions with no foundation.
The offer comparability grid
Quote item | What must be made explicit | Notes |
Configuration | Series, bore, stroke, type of mounting, options (sensors, treatments) with catalogue codes | Two prices referring to different configurations describe different objects: every option included or excluded shifts the price |
Testing | Whether it is included in the price, on what share of the pieces (100% or sample), at what pressure (ISO 10100: 1.5× nominal), with what records | A piece tested on the bench and one not tested have the same apparent price but not the same content |
Materials and seals | Rod material and treatment, type of seals | Undeclared components can be neither compared between offers nor checked on delivery |
Documentation | Datasheet with operating and test pressures, 2D/3D CAD models | Without documentation, integration into design drawings and design checks remain a cost borne by the buyer |
Lead times and continuity | Delivery date (binding or indicative), channel for urgent requests with defined times, availability of spare parts over the years | The value of a supply includes the ability to restore operation: downtime is measured in resupply time |
CAD configurator: the specification that makes offers comparable
The online CAD configurator (active since 2004) generates an unambiguous configuration (series, bore, stroke, mountings, options) with the corresponding 2D/3D CAD model: it is exactly the complete specification on which a quote becomes comparable, and it can also be used as the basis for the request for quotation to other internal stakeholders (design, purchasing).
ISO range, 100% tested
The Conforti hydraulic cylinder range complies with ISO 6020/2 (CD/DK/MD tie-rod series, 160 bar operating pressure; HD/HK counterflange series, 210 bar) and ISO 6022 (DP series for heavy duty applications, 250 bar), with every cylinder individually tested to ISO 10100 and data recorded; for urgent requests, supply within 48 hours is available. These are the items of the grid, declared in the catalogue and therefore already comparable.