{"id":3184,"date":"2026-07-08T10:29:03","date_gmt":"2026-07-08T02:29:03","guid":{"rendered":"https:\/\/prancehydraulic.com\/blog\/hydraulic-cast-iron-gear-pump-guide\/"},"modified":"2026-11-01T14:10:57","modified_gmt":"2026-11-01T06:10:57","slug":"hydraulic-cast-iron-gear-pump-guide","status":"publish","type":"post","link":"https:\/\/prancehydraulic.com\/fr\/blog\/hydraulic-cast-iron-gear-pump-guide\/","title":{"rendered":"Pompe \u00e0 engrenages hydraulique en fonte : principe de fonctionnement, sp\u00e9cifications et applications"},"content":{"rendered":"<div class=\"b2b-article\" style=\"max-width: 820px; margin: 0 auto;\">\n<p style=\"margin: 0 0 16px; line-height: 1.7;\"><strong>Hydraulic Cast Iron Gear pump<\/strong> \u2014 Cast iron hydraulic gear pumps use positive displacement gear meshing to move fluid in mobile and industrial circuits where rugged housings and moderate-to-high pressure are required. This guide focuses on hydraulic sizing, application fit, and procurement documentation for export and industrial buyers. Cross-check public data on prancehydraulic.com and confirm project limits with your design engineer.<\/p>\n<nav style=\"background: #f7f9fb; border: 1px solid #e3e8ee; border-radius: 8px; padding: 14px 18px; margin: 0 0 24px;\">\n<p style=\"margin: 0 0 16px; line-height: 1.7;\"><strong>On this page<\/strong><\/p>\n<ul style=\"margin: 0 0 18px 1.2em; line-height: 1.7;\">\n<li style=\"margin: 0 0 16px; line-height: 1.7;\"><a href=\"#part-1-core-concepts-and-working-principle\">Part 1. Core Concepts and Working Principle<\/a><\/li>\n<li style=\"margin: 0 0 16px; line-height: 1.7;\"><a href=\"#part-2-specifications-limits-and-selection-crite\">Part 2. Specifications, Limits, and Selection Criteria<\/a><\/li>\n<li style=\"margin: 0 0 16px; line-height: 1.7;\"><a href=\"#part-3-field-application-and-installation-notes\">Part 3. Field Application and Installation Notes<\/a><\/li>\n<li style=\"margin: 0 0 16px; line-height: 1.7;\"><a href=\"#part-4-documentation-and-handover-checklist\">Part 4. Documentation and Handover Checklist<\/a><\/li>\n<li style=\"margin: 0 0 16px; line-height: 1.7;\"><a href=\"#part-5-commissioning-monitoring-and-long-term-op\">Part 5. Commissioning, Monitoring, and Long-Term Operations<\/a><\/li>\n<\/ul>\n<\/nav>\n<figure class=\"prance-original-photo\" style=\"margin:24px 0\"><img src=\"https:\/\/prancehydraulic.com\/wp-content\/uploads\/2026\/05\/HDH2D10A0L24S3H-1.webp\" alt=\"Original catalog photograph: External Gear Pump HDH\" width=\"800\" height=\"800\" loading=\"lazy\" decoding=\"async\" style=\"display:block;max-width:100%;height:auto;margin:auto\"\/><figcaption>External Gear Pump HDH. Original catalog photograph; exterior reference only. This is not a photograph of the test, fault or installation described. Confirm the exact configuration from its documentation.<\/figcaption><\/figure>\n<h2 id=\"part-1-core-concepts-and-working-principle\" style=\"margin: 42px 0 14px; font-size: 1.35em; line-height: 1.3;\">Part 1. Core Concepts and Working Principle<\/h2>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">This section explains how hydraulic cast iron gear pump fits in open-circuit and industrial hydraulic systems as a positive-displacement component.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Buyers should confirm displacement, rated pressure, speed limits, and fluid compatibility before comparing quotations.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Misalignment between catalog peaks and actual duty cycle is a common source of overheating, noise, and early wear.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Size displacement from required flow at actual shaft speed: Q \u2248 displacement \u00d7 speed \u00d7 volumetric efficiency factor.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Confirm inlet conditions\u2014line size, height, temperature, and fluid viscosity at cold start\u2014not only steady-state catalog data.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Cross-check <a href=\"https:\/\/prancehydraulic.com\/product\/external-gear-pump-hdh\/\">Prance Hydraulic product line<\/a> against your circuit pressure, relief setting, and filtration plan.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">For export machines, confirm port standards (SAE\/ISO), rotation, and shaft type before issuing PO.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Include duty pressure, flow, fluid type, ambient temperature, and duty cycle in every RFQ.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Confirm imperial and metric port and shaft dimensions for export machines before fabrication.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Define warranty response, spare parts lead time, and who performs startup in the purchase order.<\/p>\n<div class=\"tip-box\" style=\"border-left: 4px solid #2e7d32; background: #f3faf4; padding: 12px 16px; margin: 0 0 18px; line-height: 1.7;\"><strong>Tip:<\/strong> Request duty-point data sheets, not marketing summaries alone.<\/div>\n<h2 id=\"part-2-specifications-limits-and-selection-crite\" style=\"margin: 42px 0 14px; font-size: 1.35em; line-height: 1.3;\">Part 2. Specifications, Limits, and Selection Criteria<\/h2>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Continuous versus intermittent pressure ratings must match your relief valve setting and load cycle.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Inlet conditions, filtration (ISO 4406), and fluid viscosity at cold start affect both performance and service life.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Mounting, shaft, rotation, and port orientation should be frozen before mechanical design sign-off.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Case drain lines on piston units must return to tank without excessive backpressure; plug unused ports per manufacturer guidance.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Parallel pump circuits need isolation and load-sharing review to avoid fighting or overheating.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Heat exchangers or tank volume may be required when duty cycle is high\u2014do not size tank from catalog defaults alone.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Use <a href=\"https:\/\/prancehydraulic.com\/hydraulic-solutions\/\">hydraulic solutions<\/a> pages for integrated system questions that span pump, valve, and motor selection.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Include duty pressure, flow, fluid type, ambient temperature, and duty cycle in every RFQ.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Confirm imperial and metric port and shaft dimensions for export machines before fabrication.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Define warranty response, spare parts lead time, and who performs startup in the purchase order.<\/p>\n<table style=\"width: 100%; border-collapse: collapse; margin: 0 0 20px;\">\n<thead>\n<tr>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">Parameter<\/th>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">What to verify<\/th>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">Typical source<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Pressure \/ flow<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Duty point vs continuous rating<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Manufacturer curve<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Speed range<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Motor\/pump RPM limits<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Datasheet<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Fluid \/ temperature<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Viscosity window<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">O&amp;M manual<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Filtration<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Inlet cleanliness target<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">ISO 4406 \/ OEM spec<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<figure style=\"margin: 26px 0; text-align: center;\"><\/figure>\n<div class=\"warning-box\" style=\"border-left: 4px solid #f9a825; background: #fffbf0; padding: 12px 16px; margin: 0 0 18px; line-height: 1.7;\"><strong>Important:<\/strong> Do not operate hydraulic pumps or motors without adequate inlet supply and relief protection\u2014cavitation and over-pressure cause rapid wear and safety hazards.<\/div>\n<h2 id=\"part-3-field-application-and-installation-notes\" style=\"margin: 42px 0 14px; font-size: 1.35em; line-height: 1.3;\">Part 3. Field Application and Installation Notes<\/h2>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">On site, Hydraulic Cast Iron Gear pump selection must match actual piping, tank, and relief architecture\u2014not spreadsheet assumptions alone.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Verify rotation, mounting torque, and port orientation before first pressurization.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Inlet vacuum and return backpressure limits are common root causes of premature failure.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Document startup pressure, temperature, and case drain (if applicable) at acceptance.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">After startup, log pressure, flow, case drain, and temperature at working load for baseline troubleshooting.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Seal and bearing wear often appears as noise, heat, or rising case drain before total loss of function.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Submit non-catalog duty points via <a href=\"https:\/\/prancehydraulic.com\/contact-us\/\">Prance Hydraulic engineering contact<\/a> for application review.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Keep fluid analysis on a schedule when contamination or water ingress is possible.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Include duty pressure, flow, fluid type, ambient temperature, and duty cycle in every RFQ.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Confirm imperial and metric port and shaft dimensions for export machines before fabrication.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Define warranty response, spare parts lead time, and who performs startup in the purchase order.<\/p>\n<table style=\"width: 100%; border-collapse: collapse; margin: 0 0 20px;\">\n<thead>\n<tr>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">Check item<\/th>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">Why it matters<\/th>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">Typical owner<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Inlet \/ return line size<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Prevents cavitation and overheating<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Hydraulic designer<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Relief setting vs component rating<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Prevents over-pressure damage<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Commissioning<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Filtration beta ratio<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Protects clearances<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Maintenance<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">As-built schematic<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Supports future service<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Owner O&amp;M<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<div class=\"tip-box\" style=\"border-left: 4px solid #2e7d32; background: #f3faf4; padding: 12px 16px; margin: 0 0 18px; line-height: 1.7;\"><strong>Tip:<\/strong> Photograph nameplates and port labels during acceptance\u2014they are required for correct spare parts.<\/div>\n<div class=\"tip-box\" style=\"border-left: 4px solid #2e7d32; background: #f3faf4; padding: 12px 16px; margin: 0 0 18px; line-height: 1.7;\"><strong>Tip:<\/strong> Archive baseline pressure, flow, and temperature readings after commissioning.<\/div>\n<h2 id=\"part-4-documentation-and-handover-checklist\" style=\"margin: 42px 0 14px; font-size: 1.35em; line-height: 1.3;\">Part 4. Documentation and Handover Checklist<\/h2>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Industrial acceptance relies on documented ratings and test evidence\u2014not verbal assurances.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Use the tables below as a hydraulic RFQ and handover starting point; your EPC contract may require more.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Cross-check <a href=\"https:\/\/prancehydraulic.com\/product\/external-gear-pump-hdh\/\">related Prance Hydraulic product pages<\/a> for public specifications and request gaps in writing.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Normalize Incoterms, warranty, and commissioning scope when comparing suppliers.<\/p>\n<table style=\"width: 100%; border-collapse: collapse; margin: 0 0 20px;\">\n<thead>\n<tr>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">Document \/ item<\/th>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">Purpose<\/th>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">When to request<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Performance \/ displacement curve<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Verify flow at speed and pressure<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Before purchase order<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Mounting \/ shaft \/ port drawing<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Mechanical and piping design<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Design phase<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Filtration and fluid spec<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Prevent premature wear<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Before first fill<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Spare seal \/ kit list<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Lifecycle planning<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Contract negotiation<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Commissioning checklist<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Acceptance at duty point<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Before handover<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<table style=\"width: 100%; border-collapse: collapse; margin: 0 0 20px;\">\n<thead>\n<tr>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">Application<\/th>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">Typical component<\/th>\n<th style=\"border: 1px solid #d9e1e8; padding: 9px 12px; background: #f4f7fa; text-align: left;\">Selection note<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Mobile construction auxiliaries<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Gear or piston pump<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Confirm pressure, speed, and tank size<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Industrial power unit<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Gear, vane, or piston pump<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Match displacement to motor RPM and relief setting<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Crane \/ drill rig drives<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Piston motor (e.g. A6VM class)<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Check case drain and speed limits<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Wheel \/ conveyor drive<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Orbit motor<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Size displacement for torque at low speed<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Direction \/ proportional control<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Solenoid or proportional valve<\/td>\n<td style=\"border: 1px solid #d9e1e8; padding: 9px 12px; vertical-align: top;\">Match flow, pressure drop, and electrical interface<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<div class=\"tip-box\" style=\"border-left: 4px solid #2e7d32; background: #f3faf4; padding: 12px 16px; margin: 0 0 18px; line-height: 1.7;\"><strong>Tip:<\/strong> Store factory test reports with the component serial number.<\/div>\n<div class=\"tip-box\" style=\"border-left: 4px solid #2e7d32; background: #f3faf4; padding: 12px 16px; margin: 0 0 18px; line-height: 1.7;\"><strong>Tip:<\/strong> Keep fluid analysis reports with the machine maintenance file.<\/div>\n<h2 id=\"part-5-commissioning-monitoring-and-long-term-op\" style=\"margin: 42px 0 14px; font-size: 1.35em; line-height: 1.3;\">Part 5. Commissioning, Monitoring, and Long-Term Operations<\/h2>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Commissioning should verify performance at working pressure and speed, not only correct rotation direction.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Log baseline pressure, temperature, case drain (if fitted), and noise at acceptance load.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Train maintenance on lockout\/tagout, filter change intervals, and fluid sampling procedures.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Trend case drain and temperature in service\u2014step changes often precede seal or bearing failure.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">After circuit modifications, re-verify relief settings and hose ratings before returning to production.<\/p>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Keep spare seal kits and critical filters based on lead time and downtime cost.<\/p>\n<div class=\"tip-box\" style=\"border-left: 4px solid #2e7d32; background: #f3faf4; padding: 12px 16px; margin: 0 0 18px; line-height: 1.7;\"><strong>Tip:<\/strong> Re-sample fluid after the first 100 hours if the system was flushed at commissioning.<\/div>\n<h2 style=\"margin: 42px 0 14px; font-size: 1.35em; line-height: 1.3;\">Recommended Prance Hydraulic Products<\/h2>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">For project support, explore our <a href=\"https:\/\/prancehydraulic.com\/product\/external-gear-pump-hdh\/\">related product line<\/a>, <a href=\"https:\/\/prancehydraulic.com\/hydraulic-solutions\/\">solution options<\/a>, and <a href=\"https:\/\/prancehydraulic.com\/about-us\/\">OEM\/ODM capabilities<\/a> on prancehydraulic.com.<\/p>\n<figure class=\"prance-original-photo\" style=\"margin:24px 0\"><img src=\"https:\/\/prancehydraulic.com\/wp-content\/uploads\/2026\/05\/HDH2D10A0L24S3H-2.webp\" alt=\"Original catalog photograph: External Gear Pump HDH\" width=\"800\" height=\"800\" loading=\"lazy\" decoding=\"async\" style=\"display:block;max-width:100%;height:auto;margin:auto\"\/><figcaption>External Gear Pump HDH. Original catalog photograph; exterior reference only. This is not a photograph of the test, fault or installation described. Confirm the exact configuration from its documentation.<\/figcaption><\/figure>\n<h2 style=\"margin: 42px 0 14px; font-size: 1.35em; line-height: 1.3;\">FAQ<\/h2>\n<h3 style=\"margin: 28px 0 10px; font-size: 1.15em; line-height: 1.35;\">What is a cast iron hydraulic gear pump?<\/h3>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">It is a positive-displacement pump with cast iron housing and meshing gears that move a fixed volume of hydraulic fluid each revolution.<\/p>\n<h3 style=\"margin: 28px 0 10px; font-size: 1.15em; line-height: 1.35;\">How does a hydraulic gear pump work?<\/h3>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Gear teeth separate at the inlet to draw fluid in, carry it around the housing, and force it out at the outlet as teeth mesh again.<\/p>\n<h3 style=\"margin: 28px 0 10px; font-size: 1.15em; line-height: 1.35;\">What pressure can a cast iron gear pump handle?<\/h3>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Many industrial and mobile cast iron designs are specified in roughly 200\u2013300 bar (about 2900\u20134350 psi); confirm continuous vs peak ratings on the datasheet.<\/p>\n<h3 style=\"margin: 28px 0 10px; font-size: 1.15em; line-height: 1.35;\">What is the difference between external and internal gear pumps?<\/h3>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">External gear pumps use two external gears; internal designs use a crescent partition and often run quieter with good high-viscosity suction performance.<\/p>\n<h3 style=\"margin: 28px 0 10px; font-size: 1.15em; line-height: 1.35;\">Where are cast iron gear pumps used?<\/h3>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Common uses include construction and agricultural auxiliaries, industrial power units, lubrication circuits, and moderate-pressure transfer lines.<\/p>\n<h3 style=\"margin: 28px 0 10px; font-size: 1.15em; line-height: 1.35;\">How do you size a hydraulic gear pump?<\/h3>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Calculate required flow from displacement \u00d7 shaft speed, then verify pressure rating, inlet conditions, fluid viscosity, and filtration match the duty cycle.<\/p>\n<h3 style=\"margin: 28px 0 10px; font-size: 1.15em; line-height: 1.35;\">Why use cast iron instead of aluminum for gear pumps?<\/h3>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Cast iron adds rigidity and damping under cyclic pressure; aluminum may be lighter but is selected when weight matters and duty is less severe.<\/p>\n<h3 style=\"margin: 28px 0 10px; font-size: 1.15em; line-height: 1.35;\">What filtration is required for hydraulic gear pumps?<\/h3>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\">Manufacturer literature often references ISO 4406 cleanliness around 18\/16\/13 at the pump inlet\u2014finer filtration generally extends gear and bearing life.<\/p>\n<h2 style=\"margin: 42px 0 14px; font-size: 1.35em; line-height: 1.3;\">References<\/h2>\n<ul style=\"margin: 0 0 18px 1.2em; line-height: 1.7;\">\n<li><a href=\"https:\/\/www.michael-smith-engineers.co.uk\/resources\/useful-info\/gear-pumps\" rel=\"nofollow noopener\" target=\"_blank\">Michael Smith Engineers \u2014 Gear Pumps<\/a><\/li>\n<li><a href=\"https:\/\/powersource.danfoss.com\/products\/pumps\/mobile-pumps\/gear-pumps\/rugid-cast-iron-gear-pumps?tab=overview\" rel=\"nofollow noopener\" target=\"_blank\">Danfoss PowerSource \u2014 Rugid cast iron gear pumps<\/a><\/li>\n<li><a href=\"https:\/\/assets.danfoss.com\/documents\/238589\/AI299873918277en-000103.pdf\" rel=\"nofollow noopener\" target=\"_blank\">Danfoss XD Series datasheet<\/a><\/li>\n<li><a href=\"https:\/\/prancehydraulic.com\/product\/external-gear-pump-hdh\/\" rel=\"nofollow noopener\">Prance External Gear Pump HDH<\/a><\/li>\n<\/ul>\n<p style=\"margin: 0 0 16px; line-height: 1.7;\"><strong>Ready to discuss your project?<\/strong> Contact <a href=\"https:\/\/prancehydraulic.com\/contact-us\/\">Prance Hydraulic engineering support<\/a> with your project parameters and technical requirements.<\/p>\n<\/div>\n<p><script type=\"application\/ld+json\">{\"@context\": \"https:\/\/schema.org\", \"@type\": \"FAQPage\", \"mainEntity\": [{\"@type\": \"Question\", \"name\": \"What is a cast iron hydraulic gear pump?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"It is a positive-displacement pump with cast iron housing and meshing gears that move a fixed volume of hydraulic fluid each revolution.\"}}, {\"@type\": \"Question\", \"name\": \"How does a hydraulic gear pump work?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Gear teeth separate at the inlet to draw fluid in, carry it around the housing, and force it out at the outlet as teeth mesh again.\"}}, {\"@type\": \"Question\", \"name\": \"What pressure can a cast iron gear pump handle?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Many industrial and mobile cast iron designs are specified in roughly 200\u2013300 bar (about 2900\u20134350 psi); confirm continuous vs peak ratings on the datasheet.\"}}, {\"@type\": \"Question\", \"name\": \"What is the difference between external and internal gear pumps?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"External gear pumps use two external gears; internal designs use a crescent partition and often run quieter with good high-viscosity suction performance.\"}}, {\"@type\": \"Question\", \"name\": \"Where are cast iron gear pumps used?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Common uses include construction and agricultural auxiliaries, industrial power units, lubrication circuits, and moderate-pressure transfer lines.\"}}, {\"@type\": \"Question\", \"name\": \"How do you size a hydraulic gear pump?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Calculate required flow from displacement \u00d7 shaft speed, then verify pressure rating, inlet conditions, fluid viscosity, and filtration match the duty cycle.\"}}, {\"@type\": \"Question\", \"name\": \"Why use cast iron instead of aluminum for gear pumps?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Cast iron adds rigidity and damping under cyclic pressure; aluminum may be lighter but is selected when weight matters and duty is less severe.\"}}, {\"@type\": \"Question\", \"name\": \"What filtration is required for hydraulic gear pumps?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Manufacturer literature often references ISO 4406 cleanliness around 18\/16\/13 at the pump inlet\u2014finer filtration generally extends gear and bearing life.\"}}]}<\/script><br \/>\n<script type=\"application\/ld+json\">{\"@context\": \"https:\/\/schema.org\", \"@type\": \"BlogPosting\", \"headline\": \"Hydraulic Cast Iron Gear Pump: Working Principle, Specs & Applications\", \"description\": \"Learn how cast iron hydraulic gear pumps work, typical 200\u2013300 bar ratings, sizing tips, and applications in construction, agriculture, and industrial circuits.\", \"keywords\": \"Hydraulic Cast Iron Gear pump\", \"inLanguage\": \"en-US\", \"author\": {\"@type\": \"Organization\", \"name\": \"Wenzhou Prance Hydraulic Equipment Co., Ltd.\", \"url\": \"https:\/\/prancehydraulic.com\"}, \"publisher\": {\"@type\": \"Organization\", \"name\": \"Wenzhou Prance Hydraulic Equipment Co., Ltd.\", \"url\": \"https:\/\/prancehydraulic.com\", \"logo\": {\"@type\": \"ImageObject\", \"url\": \"https:\/\/prancehydraulic.com\/wp-content\/uploads\/2026\/03\/cropped-favicon.webp\"}}, \"mainEntityOfPage\": {\"@type\": \"WebPage\", \"@id\": \"https:\/\/prancehydraulic.com\/blog\/hydraulic-cast-iron-gear-pump-guide\/\"}, \"url\": \"https:\/\/prancehydraulic.com\/blog\/hydraulic-cast-iron-gear-pump-guide\/\", \"image\": \"https:\/\/prancehydraulic.com\/wp-content\/uploads\/2026\/05\/HDH2D10A0L24S3H-3.webp\", \"datePublished\": \"2026-07-08\", \"dateModified\": \"2026-07-11\"}<\/script><br \/>\n<!-- prance-internal-link-backfill --><\/p>\n<section class=\"pls-related-products\">\n<h2>Related products and next steps<\/h2>\n<ul>\n<li><a href=\"https:\/\/prancehydraulic.com\/product\/external-gear-pump-hdh\/\">HDH External Gear Pump<\/a><\/li>\n<li><a href=\"https:\/\/prancehydraulic.com\/product\/internal-gear-pump-hg-for-plastic-injection-molding-machine\/\">HG Internal Gear Pump<\/a><\/li>\n<li><a href=\"https:\/\/prancehydraulic.com\/hydraulic-pumps\/\">Hydraulic Pumps<\/a><\/li>\n<\/ul>\n<p><em>Prance Hydraulic is an independent supplier. Third-party trademarks are referenced for compatibility search purposes only.<\/em><\/p>\n<\/section>\n","protected":false},"excerpt":{"rendered":"<p>Apprenez le fonctionnement des pompes \u00e0 engrenages hydrauliques en fonte, leurs pressions nominales typiques de 200 \u00e0 300 bars, des conseils de dimensionnement et leurs applications dans les circuits de construction, agricoles et industriels.<\/p>","protected":false},"author":5,"featured_media":2311,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-3184","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"blocksy_meta":[],"acf":[],"_links":{"self":[{"href":"https:\/\/prancehydraulic.com\/fr\/wp-json\/wp\/v2\/posts\/3184","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prancehydraulic.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prancehydraulic.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prancehydraulic.com\/fr\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/prancehydraulic.com\/fr\/wp-json\/wp\/v2\/comments?post=3184"}],"version-history":[{"count":12,"href":"https:\/\/prancehydraulic.com\/fr\/wp-json\/wp\/v2\/posts\/3184\/revisions"}],"predecessor-version":[{"id":5086,"href":"https:\/\/prancehydraulic.com\/fr\/wp-json\/wp\/v2\/posts\/3184\/revisions\/5086"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/prancehydraulic.com\/fr\/wp-json\/wp\/v2\/media\/2311"}],"wp:attachment":[{"href":"https:\/\/prancehydraulic.com\/fr\/wp-json\/wp\/v2\/media?parent=3184"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prancehydraulic.com\/fr\/wp-json\/wp\/v2\/categories?post=3184"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prancehydraulic.com\/fr\/wp-json\/wp\/v2\/tags?post=3184"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}