JPH0117402Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a casting material for pipe joints.

A technology that installs a weir in the machining section of the pipe thread and removes the weir marks during processing in order to eliminate the grinding process of the protrusions left by the weir marks during casting for cast materials for pipe fittings that have female pipe threads at the ends. Various methods have already been developed. However, in order to streamline the manufacturing process of pipe fittings, it is also necessary to automate the process of separating the pipe fitting material from the cast material taken out from the mold and connected to runners, risers, etc. Therefore, while the casting connected to the runner, riser, etc. is transported to the next process by a vibrating conveyor, vibration is applied to the casting, and the self-weight of the riser, etc. is used to move the casting in a direction perpendicular to the parting surface of the casting. However, there was a problem in that pipe joint materials with relatively large diameters could not be completely broken using the conventional dam structure.

The present invention provides a casting material for a pipe joint having a structure in which weir marks can be removed during processing of pipe threads, and the weir can also be automatically broken.

This will be explained below by giving examples. FIG. 1 is a longitudinal cross-sectional view of the end surface of a material for a pipe joint into which a female pipe thread is machined, taken along a cut-off plane, and a thread machining allowance 2 is formed on the inner diameter side of the end of the pipe joint material 1. 3 is an end face of the pipe joint material 1, and as is clear from FIG. 2, a crescent-shaped wall 4 is provided over the hollow part. A weir 5 (shown in a broken state) is provided at the center of the wall 4 in the longitudinal direction. The walls 4 and the weirs 5 are formed in the mold as recesses in the core. The wall 4 may be provided on either the upper mold, the lower mold, or both of the main mold, or may be formed so as to span the upper and lower molds with the parting surface in between. The depth of the recessed portion of the core forming the wall 4 is preferably about one third of the diameter of the baseboard portion of the core.

The cast material of the pipe joint constructed as described above can be cut off in a crescent shape using a cutting edge provided at the tip of the chaser when machining pipe threads. Regarding the automatic rupture of the weir, the width A of the pipe joint at the rupture part in the radial direction (parallel to the parting surface) can be increased, so the width in the wall direction (perpendicular to the parting surface) can be increased. Even if B is pressed small, it can be easily broken by applying vibration after securing a sufficient cross-sectional area.

As explained above, the casting material for the pipe joint according to the present invention is suitable for manufacturing threaded pipe joints.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of the end of a cast material of a pipe joint according to the present invention, cut along a parting surface, and FIG. 2 is a side view of the same. 2... Removal section, 4... Wall, 5... Weir.

Claims (1)

[Scope of utility model registration request] In a pipe joint casting material 1 that is cast using a horizontally split multi-piece main mold, a crescent-shaped wall 4 is formed in the hollow part of the end surface 3 of the pipe joint casting material 1 in the direction of the main mold's parting surface.
A weir 5 is provided on the wall 4 and has a long section in the direction A parallel to the parting surface and a thin cross section in the direction B perpendicular to the parting surface.
A casting material for pipe joints characterized by the provision of.