{"id":80329,"date":"2026-10-22T01:20:00","date_gmt":"2026-10-22T01:20:00","guid":{"rendered":"https:\/\/www.ktb-europe.com\/?p=80329"},"modified":"2026-10-21T21:55:20","modified_gmt":"2026-10-21T21:55:20","slug":"industrial-vacuum-pump-types","status":"publish","type":"post","link":"https:\/\/www.ktb-europe.com\/en\/blog\/vakuumpumpe-industrie-bauarten\/","title":{"rendered":"Industrial vacuum pump: which type suits your process?"},"content":{"rendered":"

The thermoforming packaging machine suddenly takes longer before the film sits cleanly. The vacuum clamping table on the CNC router no longer holds thin panels firmly. The dryer does not reach its usual pressure. Behind all three cases is the same component: a vacuum pump that no longer delivers what the process requires \u2013 or that never really suited the process in the first place.<\/p>\n

Vacuum pumps come in many types. Each has a pressure range in which it works well, and media that it tolerates well or badly. If you need to replace a pump or select a new one, you should know these differences.<\/p>\n

This guide explains the most important industrial vacuum pumps, classifies them by pressure range and application, and shows which details you need for selection and replacement.<\/p>\n

Understanding vacuum: pressure ranges and pumping speed<\/h2>\n

Vacuum means a pressure below atmospheric pressure, which at sea level is around 1013 mbar. In practice, vacuum is usually stated as absolute pressure. The smaller the number, the better the vacuum. The common classification:<\/p>\n\n\n\n\n\n\n\n\n
Range<\/th>\nAbsolute pressure<\/th>\nTypical applications<\/th>\n<\/tr>\n<\/thead>\n
Rough vacuum<\/td>\nAtmosphere to 1 mbar<\/td>\nPackaging, holding and clamping, conveying, degassing<\/td>\n<\/tr>\n
Medium vacuum<\/td>\n1 to 0.001 mbar<\/td>\nVacuum drying, distillation, freeze drying<\/td>\n<\/tr>\n
High vacuum<\/td>\n0.001 to 0.0000001 mbar<\/td>\nCoating, heat treatment, analytics<\/td>\n<\/tr>\n
Ultra-high vacuum<\/td>\nbelow that<\/td>\nResearch, semiconductor technology<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Most industrial applications lie in the rough and medium vacuum ranges. Alongside the achievable ultimate pressure, what counts is the pumping speed<\/strong>, stated in m\u00b3\/h. It describes the volume of gas the pump moves per unit of time and determines how quickly a vessel is evacuated. Important: pumping speed depends on pressure and falls off close to the ultimate pressure. So look at the pumping speed curve in the data sheet, not just the nominal value.<\/p>\n

The main types<\/h2>\n

Oil-lubricated rotary vane pump<\/h3>\n

The rotary vane pump is the classic for rough and medium vacuum. An eccentrically mounted rotor with sliding vanes forms chambers that draw in, compress and expel the gas. Oil seals the gaps, lubricates and dissipates heat. Single-stage pumps typically reach ultimate pressures of around 0.1 mbar; two-stage pumps go further into the medium vacuum range.<\/p>\n

Strengths: good ultimate vacuum, compact design, wide choice. Weaknesses: the oil can be contaminated by vapours and particles, oil changes are part of regular maintenance, and an oil mist separator is needed at the exhaust. Typical uses: packaging, clamping tables, refrigeration and air-conditioning technology, laboratory systems.<\/p>\n

Dry-running rotary vane pump<\/h3>\n

The vanes are made of a self-lubricating material, usually graphite-based. The pump works without oil in the compression chamber and only reaches rough vacuum. It is suited to clean, dry air, for example in the printing industry or in handling. The vanes are wear parts.<\/p>\n

Claw vacuum pump<\/h3>\n

Two claw-shaped rotors turn against each other without contact. With no friction in the compression chamber, the pump is low-wear and compresses oil-free. It works in the rough vacuum range and is used for central vacuum supplies, in the packaging and wood industries and in conveying systems.<\/p>\n

Screw vacuum pump<\/h3>\n

Two counter-rotating screw rotors convey the gas without contact and dry. Screw pumps reach medium vacuum and tolerate vapours and, to a certain extent, condensate. They are therefore widespread in chemicals and pharmaceuticals, in drying, distillation and solvent recovery. Special versions are available for aggressive or explosive media.<\/p>\n

Liquid ring pump<\/h3>\n

An impeller rotates eccentrically in a casing partly filled with operating liquid, usually water. The rotating liquid ring forms the pumping chambers. The pump is robust and tolerates vapours, liquid carry-over and contaminated gases. Its ultimate pressure is limited by the vapour pressure of the operating liquid and rises with the liquid\u2019s temperature. Uses: chemicals, the paper industry, food, degassing.<\/p>\n

Diaphragm pump<\/h3>\n

An oscillating diaphragm conveys the gas completely oil-free. Diaphragm pumps are small, have a limited pumping speed and work in the rough vacuum range. They are found in laboratories, analytics and as backing pumps for small systems.<\/p>\n

Roots pump and turbomolecular pump<\/h3>\n

Neither works alone; both work together with a backing pump. The Roots pump<\/strong> sits as a booster in front of a rotary vane, screw or liquid ring pump and considerably increases the pumping speed in the medium vacuum range. The turbomolecular pump<\/strong> produces high vacuum and likewise needs a backing pump.<\/p>\n

Side channel blower<\/h3>\n

It produces only a low vacuum but moves large volume flows. Typical uses are pneumatic conveying systems, extraction systems and vacuum lifters with large leaks.<\/p>\n

Which type suits which process?<\/h2>\n\n\n\n\n\n\n\n\n\n\n
Process<\/th>\nCommonly used types<\/th>\nWhat matters<\/th>\n<\/tr>\n<\/thead>\n
Vacuum packaging<\/td>\nRotary vane, claw<\/td>\nfast evacuation, moisture from the product<\/td>\n<\/tr>\n
Clamping tables, handling<\/td>\nRotary vane dry or oil-lubricated, claw, side channel<\/td>\nvolume flow with leakage via workpiece and seals<\/td>\n<\/tr>\n
Drying, distillation<\/td>\nScrew, liquid ring, rotary vane with gas ballast<\/td>\nvapours, condensate, solvents<\/td>\n<\/tr>\n
Degassing of plastic melts<\/td>\nLiquid ring, screw, rotary vane with separator<\/td>\ndeposits, monomers, particles<\/td>\n<\/tr>\n
Central vacuum supply<\/td>\nClaw, screw, rotary vane<\/td>\ndemand-based control, redundancy<\/td>\n<\/tr>\n
Coating, heat treatment<\/td>\nBacking pump plus Roots or turbomolecular pump<\/td>\nhigh vacuum, pumping station<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

The selection criteria at a glance<\/h2>\n
    \n
  1. Working pressure:<\/strong> what absolute pressure does the process really need? A pump that only just reaches its ultimate pressure is working in an unfavourable part of its curve.<\/li>\n
  2. Pumping speed:<\/strong> what volume has to be evacuated in what time, and how large are the leaks in the system?<\/li>\n
  3. Medium:<\/strong> dry air, water vapour, solvents, aggressive gases, particles or dusts? This determines whether oil-lubricated, dry or liquid-sealed is the better choice.<\/li>\n
  4. Oil-free operation:<\/strong> in food, pharmaceutical or cleanroom applications, an oil-free process may be mandatory.<\/li>\n
  5. Explosion protection:<\/strong> if explosive mixtures are pumped or the pump stands in a hazardous area, it must be suitable for the relevant zone. In the EU, the legal basis for equipment is Directive 2014\/34\/EU.<\/li>\n
  6. Mode of operation:<\/strong> continuous operation, frequent start-stop cycles or operation close to atmospheric pressure affect wear and heating.<\/li>\n
  7. Maintenance and environment:<\/strong> oil changes, vane changes, operating liquid, waste heat in the room and noise level.<\/li>\n<\/ol>\n

    Typical faults and their causes<\/h2>\n