Total product quality
A Fan Data Sheet is automatically produced for any customer enquiry, enabling Witt to produce a detailed specification and quotation, typically within 24 hours. This includes technical fan specification, fan performance and motor power curves; sound prediction within various octave bands, dimension drawing; together with a total and individual component price breakdown. A simplified version of the fan selection system is available to our customers for download. This enables you to make a pre-selection of fans and to perform a sound calculation.
On receipt of order all data is automatically transferred into the requisite documentation, specifically order confirmation, parts list; purchase orders; works instructions, delivery note, manufacturer's certificate, CE conformity declaration and invoice. The individual name plates, bearing an unique reference number, are automatically created to ensure that the history of any fan and its components can be fully traced back through all stages of production and administration.
CNC based manufacture
Witt & Sohn production facilities are equipped with the latest state-of-the-art machinery. From the parts list the components are produced on computerised numerically controlled (CNC) machines to minimise throughput time and achieve precise tolerances. At all stages of administration and production every piece of information is entered only once and is checked by the customer against the Fan Data Sheet in the order confirmation. On completion of the fan, a test run and final inspection is carried out.
Product diversity and Production process
For ease of maintenance we also offer a swing-out fan type. The solid construction makes them easy to open, even after frequent use and we still achieve excellent efficiency.
All work is carried out by highly skilled production personnel. Witt & Sohn take particular pride in the level of technical expertise and commitment of their workforce, many of whom have been with the Company for 20 years or more. Witt & Sohn's ability to work with many materials is due to the high levels of welding expertise in the Company, continuously updated by an ongoing commitment to training and the achievement of appropriate welding certificates.
Witt & Sohn's modern test facilities are used to develop and test even large scale fans prior to shipment up to and including motor powers of 2 MW. For testing of fans with high voltage motors, since 2017 a seperate 10 kV supply supported by a network of transformers enables the most commonly used high voltage motors to be checked. Frequency converters up to 800 kW and soft starts up to 100 kW complete Witt's test capabilities. 50 and 60 cycles are also available.
Recent customer surveys show that more than 90% of customers recognise Witt & Sohn's products as being of excellent quality with very long life expectancy. Customer complaints (including customer errors and incomplete deliveries) are consistently less than one percent of total shipments.
Reinforcing their commitment to total quality Witt & Sohn offer an 18 months warranty after shipment (12 months after installation) on all fans. Longer warranty periods can be agreed upon in conjunction with a service contract.