Demand for gas in the UK is expected to hit a record high today, as the big freeze continues.Gas pipeline operator National Grid forecast that demand would reach 456.7m cubic metres (mcm) of gas, beating the previous record figure of 449 mcm seven years ago to the day.National Grid had to issue its second gas balancing alert, having warned on Monday that heavy users, including factories and NHS trusts, might have to cut back on consumption.Gas supplies have been withdrawn from 94 industrial companies that have 'interruptible supply' contracts in order to ensure that residential customers have adequate supplies.Many of these will switch to back-up generators, a National Grid spokeswoman said.The pipeline operator has been hit by supply problems from Norway at the worst possible time, as demand for gas hits an all time high.National Grid said Norwegian input data via the Langeled pipeline dropped off sharply this morning at around 11:00 from 70 mcm or more to around 25 mcm.