{"product_id":"heavy-duty-shop-rotary-screw-model-no-r518hg11","title":"Heavy Duty Shop Rotary  -  Screw - Model No. : R518HG11","description":"\u003ch2\u003eCastair 5HP 1-Phase Rotary Screw 80 Gallon Horizontal G11 Air End — R518HG11\u003c\/h2\u003e\n\n\u003cp\u003eThe Castair R518HG11 is a 5-horsepower, single-phase, 80-gallon horizontal rotary screw air compressor equipped with the G11 air end — Castair's heavy-duty screw element for this horsepower range. Single-phase 230V power makes this unit accessible to shops without 3-phase service. The G11 air end designation identifies the specific rotary screw element used, which affects maintenance kit selection (MKG11 is the corresponding PM kit). At 5HP rotary screw output, expect approximately 20 CFM at 100 PSI, 100% duty cycle, and the consistent quiet output that separates rotary screw from piston in a production shop environment.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eNote: Exact CFM, weight, and dimensions for the G11 variant are based on Castair's rotary screw product line conventions. The P75 air end models (R518HP75) are confirmed at 20 CFM @ 100 PSI, 44\" height, 480 lbs. Contact 866-217-0063 to confirm G11 variant specs before ordering.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003ch3\u003eG11 Air End — What This Means for Maintenance\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eAir end identification:\u003c\/strong\u003e Castair uses different rotary screw elements across their product line. The G11 designation identifies the specific screw element, which determines which filters and maintenance kit apply.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eG11 maintenance kit:\u003c\/strong\u003e Part number MKG11 — covers 5-15HP units with G11 air end. Includes 2 air filters, 4 oil filters, 1 separator filter, and 5 gallons of Cast-Lube synthetic oil at a 10% discount versus individual pricing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eG11 air filter:\u003c\/strong\u003e Part RAFG11 — paper element, ID: 2-5\/8\", OD: 3-7\/8\", height: 3-1\/8\". Stock these on the shelf.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eG11 oil filter:\u003c\/strong\u003e Part ROFD3-4-G11 — spin-on, same as the D3, D31, and D4 air ends. Widely available.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eG11 separator filter:\u003c\/strong\u003e Part RSFD3-4-6-G11-P75 — covers G11 and other common Castair air ends.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHorizontal Tank — Layout and Installation\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDimensions:\u003c\/strong\u003e 64 × 32 × 44\" (L×W×H)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow profile:\u003c\/strong\u003e The horizontal tank keeps overall height to 44 inches — suitable for shops with lower ceilings or overhead constraints.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLonger floor run:\u003c\/strong\u003e Measure 64 inches of clear wall space plus service clearance before installing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAlternative orientation:\u003c\/strong\u003e R518VG11 (vertical) is the same unit in vertical configuration. Same output, different footprint.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e5HP Rotary Screw Output — Real Shop Capacity\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cstrong\u003eExpected: approximately 20 CFM at 100 PSI\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1\/2-inch impact:\u003c\/strong\u003e 4-8 CFM — two running simultaneously, comfortable\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e3\/8-inch air ratchet:\u003c\/strong\u003e 4-6 CFM — multiple tools at once\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDA sander:\u003c\/strong\u003e 12-20 CFM — one sander at a time\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHVLP spray gun:\u003c\/strong\u003e 9-14 CFM — painting with one gun\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1-inch impact:\u003c\/strong\u003e 10-25 CFM — fine for intermittent use; continuous heavy use should step up to 7.5HP\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCastair Build Quality\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e100% duty cycle:\u003c\/strong\u003e Rotary screw design runs continuously without piston-style thermal limitations.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAll cast iron construction:\u003c\/strong\u003e Castair builds with cast iron throughout — pumps, heads, all primary components. Not aluminum.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndustrial 1725 RPM motor, full 15% service factor:\u003c\/strong\u003e Commercial grade. Runs cool, handles occasional peak loads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSingle solenoid air end control:\u003c\/strong\u003e No computers. No lockout codes. Field-repairable with standard parts.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnalog pressure and temperature gauges standard:\u003c\/strong\u003e Read at a glance without navigating menus.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh pressure and dual high temperature shutdown standard:\u003c\/strong\u003e Built-in protection. Not an option.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFactory-filled with Cast-Lube synthetic oil:\u003c\/strong\u003e 4,000-hour or one-year change interval.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuilt-in air\/oil separator with spin-on filter:\u003c\/strong\u003e Keeps oil out of compressed air. Standard spin-on format.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOff-shelf V-belts with adjustable tensioner:\u003c\/strong\u003e Available at any industrial supply.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAir\/oil lines in copper pipe:\u003c\/strong\u003e Heat and vibration resistant. Standard fittings.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAir-cooled aftercooler\/oil cooler standard:\u003c\/strong\u003e Removable for cleaning.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHour meter standard:\u003c\/strong\u003e Track actual run hours.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e10-minute auto shutdown timer:\u003c\/strong\u003e Electricity savings when air demand stops.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eASME-rated 80-gallon tank:\u003c\/strong\u003e Code-compliant for commercial installation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePre-wired magnetic starter:\u003c\/strong\u003e Connect 230V single-phase incoming power.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePressure options:\u003c\/strong\u003e 135 PSI standard, 150 or 175 PSI available.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003e2-year warranty on air end, electric motor, and tank\u003c\/strong\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eAvailable Configurations — 5HP 1-Phase Lineup\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eR518HG11 (this unit):\u003c\/strong\u003e 5HP, 1-Phase, 80 Gal Horizontal, G11 air end\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eR518VG11 (vertical):\u003c\/strong\u003e Same specs, vertical tank\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eR518HP75:\u003c\/strong\u003e 5HP, 1-Phase, 80 Gal Horizontal, P75 air end — 20 CFM @ 100 PSI — 64 × 32 × 44\" — 480 lbs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eR538HP75:\u003c\/strong\u003e 5HP, 3-Phase 230V, 80 Gal Horizontal — 20 CFM @ 100 PSI — 470 lbs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eR718HP75:\u003c\/strong\u003e 7.5HP, 1-Phase, 80 Gal Horizontal — 31 CFM @ 100 PSI — 555 lbs\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhen Does a Shop Need This vs. Stepping Up or Down?\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eRight for:\u003c\/strong\u003e Single-phase shop, 1-2 bays, steady air tool use through the day. The rotary screw never needs to rest, so one tech running tools continuously is well within spec.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStep up to 7.5HP if:\u003c\/strong\u003e Multiple techs running air tools at the same time. 31 CFM @ 100 PSI handles the overlap without pressure drop.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChoose 3-phase if:\u003c\/strong\u003e Your facility has 3-phase service. The 3-phase motor draws less amperage per leg and starts smoother.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eG11 vs. P75 air end:\u003c\/strong\u003e Both deliver the same 5HP output. The difference is the internal screw element and the corresponding maintenance parts. Confirm which model you're ordering before purchasing PM kits.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e R518HG11\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHorsepower:\u003c\/strong\u003e 5 HP\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePhase:\u003c\/strong\u003e 1-Phase\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVoltage:\u003c\/strong\u003e 230V single-phase\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTank:\u003c\/strong\u003e 80 gallon, horizontal, ASME-rated\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAir End:\u003c\/strong\u003e G11\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExpected CFM @ 100 PSI:\u003c\/strong\u003e Approximately 20 (confirm with Castair)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDimensions (L×W×H):\u003c\/strong\u003e 64 × 32 × 44\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompressor Type:\u003c\/strong\u003e Rotary screw\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDuty Cycle:\u003c\/strong\u003e 100%\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard Pressure:\u003c\/strong\u003e 135 PSI (150 or 175 PSI optional)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMotor Speed:\u003c\/strong\u003e 1725 RPM industrial, full 15% service factor\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDrive:\u003c\/strong\u003e Belt drive, off-shelf V-belts with adjustable tensioner\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLubrication:\u003c\/strong\u003e Oil-injected, Cast-Lube synthetic, 4,000-hour\/1-year interval\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eControls:\u003c\/strong\u003e Single solenoid, pre-wired magnetic starter, analog gauges, hour meter, 10-minute auto shutdown\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShutdowns:\u003c\/strong\u003e High pressure, dual high temperature (standard)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaintenance Kit:\u003c\/strong\u003e MKG11\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 2-year on air end, electric motor, and tank\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer:\u003c\/strong\u003e Castair, Inc. (Spicer, Minnesota)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat's in the Box\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eCastair rotary screw compressor with G11 air end, mounted on 80-gallon horizontal ASME tank\u003c\/li\u003e\n\u003cli\u003ePre-wired magnetic starter and controls\u003c\/li\u003e\n\u003cli\u003eAir\/oil separator with spin-on filter\u003c\/li\u003e\n\u003cli\u003eAir-cooled aftercooler\/oil cooler\u003c\/li\u003e\n\u003cli\u003eHour meter\u003c\/li\u003e\n\u003cli\u003ePre-filled with Cast-Lube synthetic oil\u003c\/li\u003e\n\u003cli\u003eAnalog pressure and temperature gauges\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhy Buy From Air Compressor Factory Direct?\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCastair specialist:\u003c\/strong\u003e We know the G11 vs P75 air end difference and can make sure you order the right PM kit from the start\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFree shipping\u003c\/strong\u003e on qualifying orders\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFree technical support:\u003c\/strong\u003e Call 866-217-0063 — we stock and support the full Castair line\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFull manufacturer warranty\u003c\/strong\u003e honored and supported\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHonest guidance:\u003c\/strong\u003e If the 7.5HP unit is what your shop actually needs, we'll tell you\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\u003cstrong\u003eCall 866-217-0063 for quick answers and help!\u003c\/strong\u003e\u003c\/p\u003e","brand":"Cast Air","offers":[{"title":"Default Title","offer_id":53342581588181,"sku":"R518HG11","price":7804.7,"currency_code":"USD","in_stock":true}],"url":"https:\/\/aircompressorfactorydirect.com\/products\/heavy-duty-shop-rotary-screw-model-no-r518hg11","provider":"Air Compressor Factory Direct","version":"1.0","type":"link"}