McElroy 2CU, Руководство оператора

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Overview
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Theory of Heat Fusion
The principle of heat fusion is to heat two pipe surfaces to a designated
temperature, and then fuse them together by application of force. This
develops pressure which causes flow of the melted materials, which
causes mixing and thus fusion. When the thermoplastic material is heated,
the molecular structure is transformed into an amorphous condition. When
fusion pressure is applied, the molecules from each thermoplastic part mix.
As the joint cools, the molecules return to their form, the original interfaces
are gone, and the fitting and pipe have become one monolithic unit. A
strong, fully leak tight connection is the result.
The principal operations include:
Clamping The pipe pieces are held axially and radially to allow all
subsequent operations to take place.
Facing
The pipe ends are faced to establish clean, parallel mating
surfaces perpendicular to the centerline of the pipes.
Aligning The pipe ends are aligned with each other to minimize
mismatch of the pipe walls.
Heating
A melt pattern that penetrates into the pipe is formed around
both pipe ends.
Fusing The melt patterns are joined with a specified force, which is
constant around the pipe interfacial area.
Cooling
The fusion joint is held immobile with a specified force until
adequately cooled.
Inspecting Visually examine the entire circumference of the joint for
compliance with the standard or fusion procedure used.
TX04660-04-18-16
PH00363B-1-4-9
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