The labor union of Hyundai Heavy Industries said Thursday it is set to go on a partial strike next week, demanding a significant raise in their salary.

The unionized workers said they will launch a three-hour strike on Wednesday and the high-ranking officials of the union will begin a seven-hour strike daily, starting next Friday.

The union members are demanding up to 127,560 won ($107.44) increase in their monthly base pay, double their special wage for living in rural areas and abolishment of the performance-based pay system. The management has maintained its stance to freeze the pay.

The union is also requesting the adoption of an ordinary wage system, based on the Seoul Central District Court’s latest ruling earlier this year.

Market watchers said it would not be easy for the management and workers to reach an agreement as the two sides have a wide gap in their view.

The shipbuilder is already reeling from a prolonged slump, recording 171 billion won loss in the second quarter.

The company’s partner firms are voicing concerns about the union’s move, especially after other major shipbuilders have adopted a wage freeze due to the recent industry downfall hit by the sluggish offshore plant business.

Daewoo Shipbuilding & Marine Engineering, Hanjin Heavy Industries & Construction and STX all have announced a wage freeze, according to reports.

Meanwhile, the union is being criticized for its decision to grant monetary rewards to workers who participate in the strike. The union is reportedly giving gift certificates to substitute their hourly pay at work.

“In the case of Hyundai Motor’s labor union, absentees are given penalties for not joining the strike. But for Hyundai Heavy, we have too many absentees due to the nature of this job. So we decided to give incentives to those who join the move, instead of taking disciplinary action on others,” a union member said.

By Suk Gee-hyun (monicasuk@heraldcorp.com)