RED Matthews
Well-Known Member
Hello you FORUM people. I just finished this dissertation to tell a man how the bird-swing happens in the ABM production of Blow and Blow process bottles. I decided to post it here for your reading, and understanding. If you have questions, you will just have to get back to me with them.
This bottle was made on an ABM (Automatic Bottle Machine) and it was more than likely made on an Emhart IS Machine. ( IS standing for Individual Section).
In this process this bottle would be made upside down in the first stage of manufacturing. The gob of glass is dropped from the orifice ring shear off - into a delivery shoot system that takes it to the blank mold (the parison shaping mold) on the back side of the glass machine. The blank mold is in a closed position and it was closed around a part called the neckring that is operated and carried in an inverting arm system.
That neckring has a guide ring inside of the assembly that is responsible for shaping the top sealing round surface of the finish. Inside that assembly sets a Blow and Blow plunger in the up position.
When the hot gob of glass is dropped it goes through a funnel (a piece of mold equipment) and into the top end of the parison mold cavity. After the dropped gob is in the blank mold, the funnel arm carries it back away from the action and another arm swings in placing a baffle in the recessed top of the parison mold. Air is blown into the parison mold cavity which pushes the molten glass down into the neck area of the potential bottle parison and forms the bottle finish.
Then the little plunger is pulled back down leaving a little cavity in that end of the gob. Then air pressure blows the hot glass up into the little cavity creating a hollow bottle form that is called the parison.
The distribution of the glass thickness in the Final Blow Mold is determined by the shape of this blank mold cavity.
After that has happened - the blank mold opens and the arm with the glass still in the neckring is carried up and over to the Final Blow Mold side of the machine where it is waiting open for the parisons' delivery.
At this point the Final Blow Mold arms close the mold around the parison and an arm carrying the blowhead, comes over the finish end; which sticks up out of the mold, and delivers a blast of air into the parison blowing the parison glass out to the mold cavity and down to the bottom plate.
After that the mold opens and a take-out jaw lifts the bottle out and onto a dead plate near the hot end conveyor. From there a push-out arm sweeps the finished bottle out on the hot end belt
Now then - in that inverting motion of the parison form throwing the hot glass up and over to the final mold position. If the glass is a little too hot in temperature, the inverting motion can cause the inside walls of that parison to touch each others inside walls. Then when the final blow occurs the contacted glass will stretch and pull a birds-swing across the bottles cavity. So that is how they are created.
Inspection equipment normally catches them before they get to the product packaging system on the finished bottle end of the annealing lehr.
I just decided that a lot of people collecting bottles might not know how this anomaly happens.
RED Matthews
This bottle was made on an ABM (Automatic Bottle Machine) and it was more than likely made on an Emhart IS Machine. ( IS standing for Individual Section).
In this process this bottle would be made upside down in the first stage of manufacturing. The gob of glass is dropped from the orifice ring shear off - into a delivery shoot system that takes it to the blank mold (the parison shaping mold) on the back side of the glass machine. The blank mold is in a closed position and it was closed around a part called the neckring that is operated and carried in an inverting arm system.
That neckring has a guide ring inside of the assembly that is responsible for shaping the top sealing round surface of the finish. Inside that assembly sets a Blow and Blow plunger in the up position.
When the hot gob of glass is dropped it goes through a funnel (a piece of mold equipment) and into the top end of the parison mold cavity. After the dropped gob is in the blank mold, the funnel arm carries it back away from the action and another arm swings in placing a baffle in the recessed top of the parison mold. Air is blown into the parison mold cavity which pushes the molten glass down into the neck area of the potential bottle parison and forms the bottle finish.
Then the little plunger is pulled back down leaving a little cavity in that end of the gob. Then air pressure blows the hot glass up into the little cavity creating a hollow bottle form that is called the parison.
The distribution of the glass thickness in the Final Blow Mold is determined by the shape of this blank mold cavity.
After that has happened - the blank mold opens and the arm with the glass still in the neckring is carried up and over to the Final Blow Mold side of the machine where it is waiting open for the parisons' delivery.
At this point the Final Blow Mold arms close the mold around the parison and an arm carrying the blowhead, comes over the finish end; which sticks up out of the mold, and delivers a blast of air into the parison blowing the parison glass out to the mold cavity and down to the bottom plate.
After that the mold opens and a take-out jaw lifts the bottle out and onto a dead plate near the hot end conveyor. From there a push-out arm sweeps the finished bottle out on the hot end belt
Now then - in that inverting motion of the parison form throwing the hot glass up and over to the final mold position. If the glass is a little too hot in temperature, the inverting motion can cause the inside walls of that parison to touch each others inside walls. Then when the final blow occurs the contacted glass will stretch and pull a birds-swing across the bottles cavity. So that is how they are created.
Inspection equipment normally catches them before they get to the product packaging system on the finished bottle end of the annealing lehr.
I just decided that a lot of people collecting bottles might not know how this anomaly happens.
RED Matthews