Size a jockey pump to replace normal system leakage and small pressure losses without meeting sprinkler or hose demand and without repeatedly starting the main fire pump. Determine realistic leakage, system volume and pressure behavior, required pressure, acceptable run time, and the coordinated start-stop sequence. Select a small pump whose curve can reach the intended stop pressure at low flow, then verify that a genuine fire demand produces enough pressure decay to start the main fire pump. Keep the calculation and acceptance record with the final project documents so future tests use the same basis.
السلام والنشاط: مضخات الحريق ومحركاتها هي معدات للسلامة في الحياة. يجب أن تتوافق أعمال الأنظمة الهيدروليكية، والكهربائية، والديزل، والوقود، والبطاريات، والضغط، والمعدات الدوارة، والاختبار، وتعطيل الأنظمة مع التصميم الحالي المعتمد، وتتعليمات الشركة المصنعة، والمعايير المطبقة، والجهة المختصة ذات الصلاحية. يوضح هذا الدليل مسار القرار الهندسي؛ ولا يمنح الإذن بإجراء تعديلات ميدانية، أو تجاوزات، أو تشغيل بواسطة أشخاص غير مؤهلين.
Define the jockey pump's job
It maintains normal system pressure after small losses. It is not a substitute for the main fire pump and should not mask material leakage. Treat this as a system condition rather than an isolated component choice. Identify the source of every input, the unit used, the operating condition it represents, and the person responsible for approval. If information is preliminary, mark the assumption and test how the decision changes at a conservative boundary. This prevents a neat calculation from hiding an uncertain water level, pressure, valve position, driver condition, or simultaneous demand.
For jockey pump sizing, verify this section against the selected pump curve, the actual site arrangement, manufacturer instructions, and the current requirements accepted by the authority having jurisdiction. Check the installed condition as well as the drawing because pipe routes, elevations, supports, controls, and access often change during construction. Record the result in a form that can be repeated during commissioning and later inspection. Do not change a safety-critical setting or isolate fire protection without the approved impairment and restoration process.
Estimate normal leakage
Use maintenance history, measured pressure decay, known valve and device leakage, and system condition. Investigate abnormal leakage instead of permanently oversizing the jockey pump. The most useful evidence is measured or approved project data, not a copied rule of thumb. Identify the source of every input, the unit used, the operating condition it represents, and the person responsible for approval. If information is preliminary, mark the assumption and test how the decision changes at a conservative boundary. This prevents a neat calculation from hiding an uncertain water level, pressure, valve position, driver condition, or simultaneous demand.
For jockey pump sizing, verify this section against the selected pump curve, the actual site arrangement, manufacturer instructions, and the current requirements accepted by the authority having jurisdiction. Check the installed condition as well as the drawing because pipe routes, elevations, supports, controls, and access often change during construction. Record the result in a form that can be repeated during commissioning and later inspection. Do not change a safety-critical setting or isolate fire protection without the approved impairment and restoration process.
Understand system volume
Large networks, tanks, and trapped air affect how quickly pressure changes. System compressibility influences cycling but does not create a universal sizing ratio. Review this condition at normal, test, and credible abnormal states before procurement. Identify the source of every input, the unit used, the operating condition it represents, and the person responsible for approval. If information is preliminary, mark the assumption and test how the decision changes at a conservative boundary. This prevents a neat calculation from hiding an uncertain water level, pressure, valve position, driver condition, or simultaneous demand.
For jockey pump sizing, verify this section against the selected pump curve, the actual site arrangement, manufacturer instructions, and the current requirements accepted by the authority having jurisdiction. Check the installed condition as well as the drawing because pipe routes, elevations, supports, controls, and access often change during construction. Record the result in a form that can be repeated during commissioning and later inspection. Do not change a safety-critical setting or isolate fire protection without the approved impairment and restoration process.
Set the required pressure range
The jockey pump must reach the approved stop pressure while its start point remains above the main fire pump start point in the coordinated sequence. The design team should turn this point into a traceable calculation or drawing note. Identify the source of every input, the unit used, the operating condition it represents, and the person responsible for approval. If information is preliminary, mark the assumption and test how the decision changes at a conservative boundary. This prevents a neat calculation from hiding an uncertain water level, pressure, valve position, driver condition, or simultaneous demand.
For jockey pump sizing, verify this section against the selected pump curve, the actual site arrangement, manufacturer instructions, and the current requirements accepted by the authority having jurisdiction. Check the installed condition as well as the drawing because pipe routes, elevations, supports, controls, and access often change during construction. Record the result in a form that can be repeated during commissioning and later inspection. Do not change a safety-critical setting or isolate fire protection without the approved impairment and restoration process.
جدول قرارات عملي
| Sizing input | Effect on jockey pump | How to verify |
|---|---|---|
| Normal leakage | Sets required makeup flow | Pressure-decay test and history |
| System volume | Affects pressure-change rate | Drawings and field behavior |
| Target pressure | Sets required head | Approved pressure sequence |
| منحنى المضخة | Shows low-flow head capability | Manufacturer curve |
| Check valves | Leakage can cause cycling | Isolation and leak checks |
| أنبوب الاستشعار | Controls measured pressure | Field route and valve position |
Check the pump curve
Select against low-flow, high-head operation. Confirm minimum stable operation, shutoff head, motor load, and manufacturer limitations. Treat this as a system condition rather than an isolated component choice. Identify the source of every input, the unit used, the operating condition it represents, and the person responsible for approval. If information is preliminary, mark the assumption and test how the decision changes at a conservative boundary. This prevents a neat calculation from hiding an uncertain water level, pressure, valve position, driver condition, or simultaneous demand.
For jockey pump sizing, verify this section against the selected pump curve, the actual site arrangement, manufacturer instructions, and the current requirements accepted by the authority having jurisdiction. Check the installed condition as well as the drawing because pipe routes, elevations, supports, controls, and access often change during construction. Record the result in a form that can be repeated during commissioning and later inspection. Do not change a safety-critical setting or isolate fire protection without the approved impairment and restoration process.
Limit short cycling
Review check-valve leakage, pressure-tank function where used, sensing line location, system volume, and the gap between start and stop settings. The most useful evidence is measured or approved project data, not a copied rule of thumb. Identify the source of every input, the unit used, the operating condition it represents, and the person responsible for approval. If information is preliminary, mark the assumption and test how the decision changes at a conservative boundary. This prevents a neat calculation from hiding an uncertain water level, pressure, valve position, driver condition, or simultaneous demand.
For jockey pump sizing, verify this section against the selected pump curve, the actual site arrangement, manufacturer instructions, and the current requirements accepted by the authority having jurisdiction. Check the installed condition as well as the drawing because pipe routes, elevations, supports, controls, and access often change during construction. Record the result in a form that can be repeated during commissioning and later inspection. Do not change a safety-critical setting or isolate fire protection without the approved impairment and restoration process.
Coordinate controls and alarms
Keep the sensing line independent and correctly arranged, protect it from blockage or trapped air, and document controller modes and alarm response. Review this condition at normal, test, and credible abnormal states before procurement. Identify the source of every input, the unit used, the operating condition it represents, and the person responsible for approval. If information is preliminary, mark the assumption and test how the decision changes at a conservative boundary. This prevents a neat calculation from hiding an uncertain water level, pressure, valve position, driver condition, or simultaneous demand.
For jockey pump sizing, verify this section against the selected pump curve, the actual site arrangement, manufacturer instructions, and the current requirements accepted by the authority having jurisdiction. Check the installed condition as well as the drawing because pipe routes, elevations, supports, controls, and access often change during construction. Record the result in a form that can be repeated during commissioning and later inspection. Do not change a safety-critical setting or isolate fire protection without the approved impairment and restoration process.
Commission the sequence
Create a controlled small pressure loss, verify jockey start and stop, then create the approved larger demand and verify main pump start without delay. The design team should turn this point into a traceable calculation or drawing note. Identify the source of every input, the unit used, the operating condition it represents, and the person responsible for approval. If information is preliminary, mark the assumption and test how the decision changes at a conservative boundary. This prevents a neat calculation from hiding an uncertain water level, pressure, valve position, driver condition, or simultaneous demand.
For jockey pump sizing, verify this section against the selected pump curve, the actual site arrangement, manufacturer instructions, and the current requirements accepted by the authority having jurisdiction. Check the installed condition as well as the drawing because pipe routes, elevations, supports, controls, and access often change during construction. Record the result in a form that can be repeated during commissioning and later inspection. Do not change a safety-critical setting or isolate fire protection without the approved impairment and restoration process.
كيف يرتبط هذا بمعدات BORRAPUMP
توفر شركة BORRAPUMP معدات ضخ هندسية لمشاريع المياه والحماية من الحريق. راجع ما يخص ذلك تكوين منتج BORRAPUMP كمنطلق، ثم قم بتقديم التدفق المطلوب، والرأس، ومصدر المياه، والمشغل، والطاقة، وأدوات التحكم، وظروف الموقع، والمتطلبات المطبقة، والكمية، والوجهة. يجب أن يستخدم الاختيار النهائي الأساس الهيدروليكي للمشروع والتقديم المعتمد؛ لا يدعي هذا الدليل أن ترتيباً واحداً في الكتالوج يناسب كل اختصاص أو مخاطرة.
أدلة BORRAPUMP ذات الصلة
- مضخات الحريق التي تعمل بالديزل مقابل الكهرباء
- اختيار منظومة مضخات الحريق
- دليل اختبار قبول المعيار NFPA 20
مراجع موثوقة
تحدد المصادر التالية حدود المعايير، وسياق السلامة من الحرائق، ومبادئ نظام المضخات المستخدمة في هذا الدليل. قم دائماً بتطبيق الإصدار والاعتماد المحلي المقبول للمشروع.
- صفحة تطوير معيار NFPA 20
- موارد أنظمة المضخات التابعة لوزارة الطاقة الأمريكية
- أبحاث المعهد الوطني للمعايير والتقنية (نيست) للحماية من الحريق
فيديو تعليمي
الخلفية التعليمية بواسطة الهندسة العملية: هل المضخات تولد ضغطاً أم تدفقاً؟. يدعم الفيديو مفهوم الهندسة الأساسي ولا يحل محل متطلبات الحماية من الحريق الخاصة بالمشروع.
الأسئلة الشائعة
Can I size a jockey pump as a percentage of the fire pump?
Do not rely on a percentage alone. Use actual leakage, system pressure behavior, the jockey curve, and approved criteria.
Why does the jockey pump short-cycle?
Possible causes include leakage, check-valve backflow, small system volume, trapped air, pressure-tank problems, or narrow settings.
Should the jockey pump handle sprinkler flow?
No. A fire demand must start the main fire pump according to the approved sequence.
Can an oversized jockey pump delay the main pump?
It can mask a growing demand or create poor control behavior, so size and test the complete sequence.
قائمة التحقق من التحقق النهائي
قبل الموافقة، قم بتأكيد الأساس الهيدروليكي، وحالة مصدر المياه، ومنحنى المضخة المختار، وبيانات المحرك ووحدة التحكم، وتصنيفات ضغط المكونات، وترتيب الصمامات، وطريقة الاختبار، وسُبل الوصول، والصرف، والإنذارات، وإجراءات إعادة التشغيل. قم بحل أي اختلافات بين المخططات والنظام المُركَّب. وأثناء التشغيل التجريبي، استخدم أدوات معايرة وسجّل ضغط السحب، وضغط الطرد، ومعدل التدفق، والسرعة، وحالة المحرك، والإنذارات، والملاحظات غير الطبيعية عند كل نقطة مطلوبة. احتفظ بالنتائج المقبولة مع سجلات غرفة المضخات لكي تُقارن عمليات الفحص اللاحقة النتائج المتشابهة ببعضها.