Pretensioner tube in retractor assembly

A seatbelt pretensioner system for use in a seatbelt pretensioning retractor assembly having a spindle and a frame, the seatbelt pretensioner system comprising:

• a housing adapted for being mounted to the frame and having an interior cavity;
• a pretensioner tube including a body portion and an exit portion, the tube having a first tube end in fluid communication with a gas generator and a second tube end in fluid communication with the interior cavity of the housing;
• a pinion rotatably mounted in the housing and fixedly coupled to the spindle adapted for taking up seatbelt webbing during pretensioning;
• a pretensioner rod disposed inside the pretensioner tube, the pretensioner rod having a proximal end disposed towards the gas generator and a distal end disposed away from the gas generator;
• a stopper disposed between the gas generator and the pretensioner rod,
• wherein the exit portion of the tube is formed with a necked down section such that the exit portion is configured to prevent the stopper from passing therethrough, and
• a flange formed at the second tube end having a circular shape to reinforce the pretensioner tube, the flange radially extending around an entire circumference of the second tube end.