M.a. Industries, Inc.

Poly-tec Products, Inc.

Craig B Williams

James A Westhoff

James A Kelly

Joseph H Montgomery

Method and apparatus for forming cast members. Steps are provided in the cast member by sliding mounting flanges of hollow plastic step inserts into slots provided in the inner mold shell. The cast material is then poured into the mold. Once the cast material has set, the cast member is withdrawn from the mold assembly. The step insert mounting flanges are broken away, leaving hollow step inserts into which manhole steps are force-fittingly mounted. The inserts are provided with integral cover tabs which cover larger slots provided to facilitate insertion of the step inserts, preventing leakage of the cast material into the mold assembly. Integral cover tabs are similarly provided on enforcement ring support members mounted in a similar fashion to insertion slots provided on one of the mold members to cover larger width slot portions to prevent seepage of cast material. Similar seals are provided by cylindrical-shaped inserts for use in wetcast and drycast fabrication methods.

Manhole insert for manufacture of a cast member and to provide a step insert having increased structural and holding strength

A non-metallic ladder for use in a manhole in which permanent manhole steps have been installed and spaced relation from the top of the manhole to a position above the bottom and there being a pair of spaced side members on said ladder connected transversely by spaced steps to form corners at the top in which there are spaces to fit over a respective side members on the step. The spaces may be in the shape of a rectangular cross-section or other configuration. The ladder is 'hung' from the step to resist dislodgment therefrom. There may be provided a wall bumper member at the bottom of the ladder to engage the inside wall of the manhole.

Manhole ladder

The present device is especially useful for positioning on forms prior to the pouring of concrete for removal therefrom to create holes in the concrete to receive inserts therein such as in making holes in concrete for steps to be used in a manhole. A tapered steel shaft of any selected length has a collar fixed near one end thereof with an elongated handle passing transversely therethrough. The collar has slanted cam edges on each end providing a cam surface which is approximately 12.degree. from a line perpendicular to the axis. A second collar identical to the first is welded to a form, such as a steel concrete form used in pouring concrete for manholes. The second collar also has slanted cam edges providing a cam surface corresponding to the slanted cam edges on the first collar and there is a hole passing through the steel pin and through the second collar to receive a removable latch pin therein. The steel pin is inserted through the second collar and fixed in place until after the concrete is poured and has cured sufficiently at which time the latch pin is disengaged and the handle is turned to rotate a cam edge of the first collar against a cam edge of the second collar thereby providing a cam action which readily disengages the pin from the concrete and leaves a hole.

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Fayetteville, GA, United States of America

Craig B Williams