blind riser

blind riser

[¦blīnd ′rī·zər]
(metallurgy)
An internal riser that does not extend to the outer surface of a mold.
References in periodicals archive ?
Rather than a blind riser, which does not reach the exterior of the mold, Reamer suggests using a runner from the gating system to feed the riser.
AG Anderson designed a new blind riser system that was able to improve casting yield and reduce labor and energy costs for large carbon and low alloy steel castings.
In order to prevent the formation of the pressurized zone, the liquid contained by the blind riser must have a free passage to the outside atmosphere.
On the carousel, the wheels are single-poured into one of two side gates, while the other gate is blocked with a mold insert to become a blind riser.
A blind riser connects the runner and the two ingates, which are opened from both sides of the riser.
The difference in the gating of this part from Case 1 is that the runner is extended after the blind riser and an open pop off is used at the end of the runner.
If a blind riser is to feed a steel casting properly, it is important that the riser neck stay open until the casting solidifies.
If it is not possible to route hot metal into the blind riser, there are other solutions such as opening the riser through the cope or enlarging its diameter.
Blind risers work on the principle of using a "firecracker" core to puncture a hole in the steel shell that sets up as the blind riser solidifies.
This puncture hole allows the atmospheric pressure to push on the liquid metal in the blind riser so that it may feed the casting.
eliminating blind risers located below an open riser with a heavy section connecting them;