{"id":5334,"date":"2026-11-10T10:00:00","date_gmt":"2026-11-10T02:00:00","guid":{"rendered":"https:\/\/prancehydraulic.com\/?p=5334"},"modified":"2026-11-10T14:17:44","modified_gmt":"2026-11-10T06:17:44","slug":"hydraulic-pump-fire-resistant-fluid-compatibility","status":"publish","type":"post","link":"https:\/\/prancehydraulic.com\/pt\/blog\/hydraulic-pump-fire-resistant-fluid-compatibility\/","title":{"rendered":"Bombas Hidr\u00e1ulicas e Fluidos Resistentes ao Fogo: Compatibilidade e Redu\u00e7\u00e3o de Capacidade"},"content":{"rendered":"
\n

Hydraulic pump compatibility with fire-resistant fluid depends on the exact pump version, the fluid formulation, and the operating conditions. A pump approved for mineral hydraulic oil is not automatically approved for water-glycol or another fire-resistant fluid. Before changing the fill, obtain written confirmation of permitted pressure, speed, temperature, viscosity, seal materials, and conversion requirements. Fire resistance addresses an ignition hazard; it does not establish lubrication performance or make a pressurized leak harmless.<\/p>\n

This guide concerns deciding whether a pump and circuit can accept a different fluid. It does not provide a universal conversion recipe or a pressure reduction that can be applied to every pump bearing a familiar series name.<\/p>\n

Start with the fluid category and the actual formulation<\/h2>\n

Fire-resistant hydraulic fluids include water-containing and water-free families. Those families behave differently, and a category alone does not identify every additive, material interaction, or service requirement. Record the manufacturer, product name, revision of its technical sheet, and the specified classification. Include the safety data sheet, but do not treat that document as a substitute for equipment approval.<\/p>\n

Water-glycol fluids require particular attention to their water balance and operating temperature. Water is part of the formulation rather than ordinary contamination to remove indiscriminately. Conversely, a water-free synthetic must not be managed using instructions written for a water-containing fluid. The fluid supplier should specify the sampling method and corrective action for the actual formulation.<\/p>\n

An old container label or an operator’s recollection is weak evidence when a machine has changed owners. If the existing fill is uncertain, have it identified before planning a conversion. Mixing two uncertain liquids creates a second problem and makes later sample results difficult to interpret.<\/p>\n

Separate three different approvals<\/h2>\n

There are three questions: whether the fluid meets its own specification, whether the pump permits that fluid, and whether the complete machine permits the combination. Passing one does not answer the other two. A fluid can meet a published classification while remaining unsuitable for a particular pump construction or brake assembly.<\/p>\n

The pump approval must identify the relevant version and service conditions. Ask whether the approval covers the installed displacement, control arrangement, bearing design, and seal package. A family-level statement can be useful for screening, but it does not justify ignoring exceptions in a model-specific document.<\/p>\n

Machine approval includes valves, actuators, hoses, accumulators, filters, reservoirs, sensors, coatings, and any shared lubrication compartments. The most restrictive component can control the conversion. Replacing pump seals alone does not establish compatibility elsewhere in the circuit.<\/p>\n

Why pressure and speed limits may change<\/h2>\n

Lubrication, density, viscosity behavior, corrosion protection, and bearing conditions can differ from the mineral-oil baseline. A manufacturer may therefore impose different operating limits or require a dedicated construction. The direction and size of the change depend on the product and fluid. There is no defensible universal percentage reduction.<\/p>\n

Treat a permitted pressure and a permitted speed as part of one operating envelope. A table might distinguish continuous duty from intermittent operation, or specify conditions at the inlet and case drain. Selecting the largest number from separate rows can create a combination the document never approved.<\/p>\n

Do not equate a reduced machine setpoint with a fully engineered conversion. A pressure adjustment does not correct an incompatible hose liner, damaged reservoir coating, excessive inlet loss, or a control circuit operating outside its viscosity requirements. Establish the complete envelope before changing settings.<\/p>\n

Build a compatibility decision table<\/h2>\n

Use the following qualitative table as a review sequence. It is a decision aid, not a specification for any Prance pump. Product-specific limits must come from the applicable component documentation and written application confirmation.<\/p>\n\n\n\n\n\n\n\n\n\n\n
Review item<\/th>\nEvidence needed<\/th>\nDecision when evidence is missing<\/th>\n<\/tr>\n<\/thead>\n
Pump construction<\/td>\nComplete code and approved fluid\/version combination<\/td>\nKeep compatibility unconfirmed<\/td>\n<\/tr>\n
Operating envelope<\/td>\nPressure, speed, viscosity and temperature limits together<\/td>\nDo not carry over mineral-oil ratings<\/td>\n<\/tr>\n
Seals and hoses<\/td>\nCompound and formulation compatibility<\/td>\nObtain material confirmation before filling<\/td>\n<\/tr>\n
Reservoir and coatings<\/td>\nCompatibility of wetted materials and internal finish<\/td>\nInspect and resolve coating uncertainty<\/td>\n<\/tr>\n
Conversion cleanliness<\/td>\nResidual-fluid and flushing requirements<\/td>\nObtain a documented changeover procedure<\/td>\n<\/tr>\n
Maintenance<\/td>\nSampling, water balance and replacement criteria<\/td>\nEstablish monitoring before commissioning<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

A useful review produces an action for each unresolved row. \u201cCheck with supplier\u201d should become a precise question identifying the component, the proposed fluid, the missing condition, and the person responsible for answering it. Otherwise the same uncertainty tends to survive into commissioning.<\/p>\n

Check the inlet and case circuit again<\/h2>\n

An existing suction line was selected for a particular fluid and temperature range. A new fluid can change pressure loss and inlet behavior. Review the pump’s inlet requirements at the lowest expected starting temperature, the proposed speed, and the actual reservoir arrangement. Do not assume that an acceptable warm reading proves adequate cold-start conditions.<\/p>\n

Case-drain requirements also remain specific to the pump. Verify permitted case pressure, routing, and any commissioning instructions. Changing fluid does not justify capping a drain or routing it through an arbitrary restriction. A shared return line can expose a pump case to transient pressure that an average gauge reading misses.<\/p>\n

Inspect filter compatibility and service criteria as well. The element material, seals, differential-pressure indication, and fluid sampling practice must suit the new service. Do not replace the original filtration requirement with a generic cleanliness target taken from another machine.<\/p>\n

Plan the changeover as a controlled maintenance job<\/h2>\n

First secure the machine, isolate energy sources, relieve stored hydraulic pressure using the approved procedure, and address accumulators and gravity loads. Fluid draining and flushing should follow an equipment-specific plan. Neither an empty reservoir nor clean-looking oil proves that cylinders, hoses, coolers, and dead-end passages are free of the previous fill.<\/p>\n

Ask the fluid and equipment suppliers to define acceptable residual contamination, cleaning materials, flushing conditions, and disposal requirements. Avoid improvising a solvent or flushing mixture. A cleaning agent that removes the previous oil may still damage seals or remain trapped in the circuit.<\/p>\n

Plan how the new fluid will enter the system without carrying dirt or incompatible residues from transfer equipment. Use identified containers and suitable transfer filtration. Record the actual product and batch. Keep samples when required by the commissioning or warranty procedure, with labels that distinguish new fluid from drained fluid.<\/p>\n

Commission against a baseline rather than a feeling<\/h2>\n

Before conversion, document the machine’s approved operating condition and any existing defects. Useful observations include pump inlet conditions, working pressure, speed, fluid temperature, case behavior, leakage, noise, and actuator response. A pre-existing fault should not become an unexplained consequence of the new fluid.<\/p>\n

After filling and commissioning according to the manufacturer, compare the same operating points. Start with the authorized procedure and stop if abnormal noise, unstable control, external leakage, unexpected heating, or other stop criteria appear. Do not keep increasing load to see whether a symptom disappears.<\/p>\n

A successful short run is only an initial result. Some compatibility problems develop over time, and fluid properties can change during service. Set a review date and sampling schedule before returning the machine to normal production. Keep the acceptance criteria specific enough that another technician can repeat the assessment.<\/p>\n

\"Variable
Variable Displacement Pump OEM A10VO 31 Series: original website product photograph, view 2. Exterior appearance does not establish the control configuration or operating limits discussed in this article.<\/figcaption><\/figure>\n

What a Prance product photograph can establish<\/h2>\n

The Prance A10VO 31-series product page provides a relevant pump enquiry starting point. Its exterior photographs help identify the catalog product being discussed. They do not prove that an installed pump has a particular seal compound, internal bearing arrangement, control option, or approval for a named fire-resistant fluid.<\/p>\n

Send the full nameplate code and clear photographs with the proposed fluid sheet when requesting an application review. Include the duty cycle, inlet arrangement, current operating conditions, and reason for conversion. If the installed unit differs from the catalog description, identify that difference explicitly instead of selecting an apparently similar replacement.<\/p>\n

Treat compatibility as unconfirmed until the exact combination is supported. This protects both the buyer and the supplier from an order based on a broad series label. It also keeps a discussion of general fluid engineering from becoming an unsupported performance claim for a particular product.<\/p>\n

\"Variable
Variable Displacement Pump OEM A10VO 31 Series: original website product photograph, view 3. Exterior appearance does not establish the control configuration or operating limits discussed in this article.<\/figcaption><\/figure>\n

Avoid the most common purchasing shortcuts<\/h2>\n

Ordering by viscosity grade alone overlooks friction, materials, water content, and approval differences. Ordering by the word \u201csynthetic\u201d is similarly incomplete. Neither label explains whether a pump can operate at the existing pressure and speed, or whether the rest of the machine accepts the formulation.<\/p>\n

Another shortcut is treating previous operation as proof of approval. A machine can run for a period with unsuitable fluid before a fault becomes visible. Conversely, a fault appearing after conversion can have several causes. Preserve samples, settings, and commissioning records so that the investigation can distinguish fluid selection from cleanliness, installation, and existing wear.<\/p>\n

For procurement, request an explicit answer: approved as supplied, approved with stated modifications and limits, or not approved. Attach the supporting document revision. A clear negative answer is more useful than a vague assurance that a fluid is \u201cnormally compatible.\u201d<\/p>\n

Questions to resolve before authorizing the fill<\/h2>\n

Does fire-resistant mean the liquid cannot burn?<\/h3>\n

No. The term describes resistance under specified conditions, not immunity to every ignition scenario. Maintain the machine’s fire controls and follow the fluid safety documentation. A high-pressure release remains hazardous regardless of the fluid classification.<\/p>\n

Can I apply the same derating to every pump?<\/h3>\n

No. Permitted changes depend on the exact pump construction, fluid, and operating conditions. Use the applicable approval envelope. A percentage copied from another product can leave the installation outside its permitted limits.<\/p>\n

Is changing the seals enough?<\/h3>\n

Not necessarily. Bearings, hoses, coatings, filters, controls, and other wetted components also require review. The conversion must address the entire affected circuit, including compartments that share the same fluid.<\/p>\n

Should water always be removed from an HFC fluid?<\/h3>\n

No. Water is an intentional part of water-containing formulations. Use the fluid supplier’s analysis and correction procedure. Do not add water or remove it based on a general mineral-oil maintenance rule.<\/p>\n

What should accompany a compatibility enquiry?<\/h3>\n

Provide the complete pump code, proposed fluid product and technical sheet, pressure and speed duty, temperature range, inlet and case arrangement, current fill, and planned changeover method. Ask for the permitted configuration and conditions in writing before procurement or filling.<\/p>\n

Related product and engineering resources<\/h2>\n

Variable Displacement Pump OEM A10VO 31 Series<\/a>, hydraulic pump product range<\/a>, How to prepare a hydraulic fluid viscosity selection record for pumps, motors, and valves<\/a>, Pressure-Compensated Pump Overshoot: Why Steady Pressure Looks Normal<\/a>. Confirm the complete product code and application requirements when requesting a configuration review.<\/p>\n

Technical references<\/h2>\n