Previously listed on the London Stock Exchange between 1986 and 1999, the Doncaster-based manufacturer signalled its intention last month to return to the market to support its growth plans. Turnover last year was £300m.
Private equity firm Cavendish Square Partners retains 23% of the ordinary shares, with directors and senior managers holding a further 9.8%.
The offer price of 245p put a market value on the company of £490m. The share price rose on the first day of trading to 250p.
Chief Executive David Hall said the flotation “demonstrates confidence in our business and gives us the financial firepower to continue our programme of investment”.