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Efficient Ventilation Molded Parts Made of Plastic - Quality You Can Breathe.


Discover a wide range of high-quality ventilation molded parts made of plastic at Kwerk GmbH. As a proud partner of HOKA, we offer PVC-U, PPs, PPs-EL, PP-H, PE-HD, and PVDF ventilation molded parts in various designs and dimensions. Our products are particularly used in corrosion-resistant extraction systems in the chemical industry, electroplating industry, paper and food industry, as well as laboratory facilities.

As a leading supplier of ventilation molded parts on our B2B platform, we provide you with access to a comprehensive selection of over 8000 molded parts, fittings, and devices for ventilation technology. From pipe bends and tees to flanges and cleaning openings - we have the right ventilation molded part for your requirements. Through our close collaboration with HOKA, we can also offer customized solutions tailored to your processes and application areas.

Our ventilation molded parts are manufactured to the highest quality standards and are characterized by reliable processing and assembly. We use modern bonding and welding techniques to ensure a robust and durable connection. In addition to our standard products, we also offer practical plug-in systems in various dimensional ranges and materials to provide you with maximum flexibility.

For optimal flow rate control, we offer a wide selection of ventilation molded parts such as dampers, cuffs, silencers, rain caps, and much more. In addition to our extensive product range, we also provide various accessories and additional services such as service and installation.

Trust the long-standing partnership between Kwerk GmbH and HOKA for first-class ventilation molded parts made of plastic. Our products meet the highest German industry standards and will reliably help you optimize your ventilation technology.

Visit our B2B platform today to obtain more information or contact us by phone. Rely on the expertise of Kwerk GmbH - your reliable partner for top-quality plastic ventilation molded parts.

Optimize your shopping experience with our detailed delivery information

Plastic pipe systems

Overview of plastic pipe systems
Technical information on ABS pipe systems
Technical information on PVC  U pipe systems
Technical information on PVC  U transparent pipe systems
Technical information on PVC  C pipe systems
Technical information on PP pipe systems
Technical information on PP-R pipe systems
Technical information on PE pipe systems
Technical information on PVDF pipe systems

Chemiedur - pipe

Technical information on UP-GF (FRP) pipe systems
UP-GF (FRP) pipes
UP-GF (FRP) molded parts and connection
UP-GF-PP (FRP) molded parts and connection
UP-GF (FRP) adhesive collars
UP-GF (FRP) loose flanges
Pot Strainer DN 200 - DN 500 Inliner PP/FRP Coated
Pot Strainer DN 200 - DN 500 Inliner FRP/CBL Coated
Angle Seat Strainer DN 200 - DN 400 Inliner FRP/CBL Coated
Manhole mad of FRP and PP/FRP

Plastic pipes

Calculator for cutting pipes
Guidelines for sawing plastic pipe
Leftovers in plastic pipe
Standardization of plastic pipes and molded parts
PVC U pipes deviations
Pressure loss in pipe systems out of PVC U, PVC C and ABS pipe systems
Distinction between Rp, R and G threads
Screw lengths for flange connections

Plastic fittings

PVC U transparent ball valves
Diaphragm valves
Block valves
Butterfly valves
Plastic needle valves


Plastic Valves according to ATEX

New EU guideline 2014/34/EU
Plastic Valves in EX zones
Y-Strainers PP-EL DN 15 - DN 50
Check valves PP-EL DN 15 - DN 50
Angle seat valves PP-EL DN 15 - DN 50

Bonding of plastic pipes

Bonding manual
Video showing the bonding of pipes

Plastic welding

Guidelines for extrusion welding

Grids / support grids

GFK grids
Grids out of PP -el electrically conductive
Profile support grids out of PP -el electrically conductive

Molded ventilation parts

Ventilation technology

Chemical hose

PVC transparent hose with fabric inlay

Industrial tanks and chemical containers

Dosing tanks and outer containers 35 – 1000 Liter
Salt dissolving tanks 60 -5000 Liter
Storage tanks and vats
Storage tanks for water
Safety and collecting troughs
Industrial tank delivery program
Dosing tanks with agitator
Dosing tank agitators
Dosing tanks with attachments
Dosing tanks made of sheet material
Customized chemical containers
Dosing tanks with level indicators



IBC screw caps DN 150/DN 200
IBC adapters out of PE
IBC adapters out of PP

Attachment parts for tank construction

Vapor separators
CO2 - absorbes
Revision nozzles
Block flange

Filter housings and filter cartridges

PENTEK 3G Slime Line filter housings
PENTEK 3G Standard filter housings
PENTEK Big Blue filter housings
PENTEK PP high temperature filter housings
PENTEK PP all nature filter housings
PENTEK filter bags for Big Blue filter housings
PENTEK surface filter cartridges
PENTEK filter cartridges for depth filtration
PENTEK filter cartridges with activated carbon
CINTROPUR filter systems
CINTROPUR water filters

Flange configurator

Blind flanges, loose flanges,  rectangular flanges

Chemical resistance

Table of chemical resistance for plastic pipe systems

Machined plastic parts

Screw-in parts
Threaded fittings
Screw fittings

Milled plastic parts

Loose flanges and blind flanges made of sheet material

Static mixers

Static mixers made of plastic


Single-type and double-type strainers
Pot strainer DN 300
Angle seat strainer DN 500

Flow meters

Variable area flow meters
Configuration tool for flow meters

Filter presses

Laboratory filter presses

Injection molded parts

Scraper made of PE for filter press

Kwerk Practice Blog

The Kwerk team blogs from the field here

Partnership at the highest level.