Abstract: A flat blow molding machine adapted to extrude flat hollow parison from clearance between a flat core and a flat die surrounding the core, characterized in that both ends of the die are slidable in a width direction with respect to a center, the core is replaceable in accordance with expansion and contraction of the die in the width direction. According to this construction, it is possible to change the width of the flat hollow parison extruded from the clearance between the core and the die by sliding the both ends of the die in the width direction and replacing the core upon expansion and contraction of the core in the width direction. Further, if the flat core is constructed from a planar replaceable portion and curved (three dimensional) non-replaceable portions and only the planar replaceable portion is exchanged upon replacement, preparing a plurality of inexpensive-to-manufacture planar replaceable portions having different lengths is enough and the cost is reduced.

Abstract: A method of fabricating a bundle-like pipe unit using a blow molding machine having a plurality of heads feeding parisons into a molding die comprises the steps of forming a plurality of hollows independent from each other in the molding die, forming one or more channels connecting the hollows to each other laterally, feeding the parisons into the hollows from the respective heads of the blow molding machine, and blowing air into the parisons in a manner such that a plurality of independent pipes are molded in the respective hollows and the pipes are joined with each other at the lateral walls thereof by the parisons which are forced into the channels upon air blowing. Suction forces are preferably applied on the parisons when the parisons are fed into the hollows of the molding die. The pipe unit thusly fabricated is light in weight and possesses flexibility as well as anti-corrosion properties due to the characteristics of the parisons.

Abstract: A method of fabricating a bundle-like pipe unit using a blow molding machine having a plurality of heads feeding parisons into a molding die includes the steps of forming a plurality of hollows independent from each other in the molding die, forming one or more channels connecting the hollows to each other laterally, feeding the parisons into the hollows from the respective heads of the blow molding machine, and blowing air into the parisons in a manner such that a plurality of independent pipes are molded in the respective hollows and the pipes are joined with each other at the lateral walls by the parisons which are forced into the channels upon air blowing. Suction forces are preferably applied on the parisons when the parisons are fed into the hollows of the molding die. The pipe unit thusly fabricated is light in weight and possesses flexibility as well as anti-corrosion properties due to the characteristics of the parisons.