Methods to Achieve Proper Cradle Dump Operation

Every bird found inside a poultry processing plant has to pass through the back dock on its way into the plant, and it is an area that is often neglected until it breaks down. Each coop that comes off the truck has to unload its birds by dumping them via the cradle dump onto another belt on their way to the hanging belt to begin the automated portion of the poultry processing journey.

There are several key factors that contribute in a positive or negative manner to the proper operation of the cradle dump section of the back dock equipment. Proper operation includes not only moving the birds from the coop to the belt conveyor in the dumping process, but to do so in a SAFE and PRODUCTIVE manner, with a controlled operation that keeps the machinery from becoming a maintenance nightmare.

The Key Factors affecting the dumping process:

• The operator. Probably the most important part of the process, and the one that is least controllable. OPERATOR SAFETY is the first and foremost consideration.
• The condition of the coops- smooth floors and interiors without wire damage is mandatory for ease of bird removal.
• The maximum angle of dump that the cradle can raise to. We have seen this angle vary from 33 to 64 degrees from horizontal.
• The velocity of the dumper cylinders and deceleration time at top and bottom.

Because the coops have doors that are spring loaded in an open and closed position, when the cradle dumps, the birds need to slide along the floor and push against the coop doors to open the doors so the birds can dump down to the belt conveyor. If the coop floor is too rough, or the dumping angle isn’t steep enough, the operator will frequently “shake” the coop (cradle dump assembly) by rapidly moving the manual hydraulic valve handle back and forth to cause the cylinders to rapidly extend and retract a short distance, causing a great deal of hydraulic and mechanical shock in the system, which causes stress cracks in the machine frame welds and premature failure of the cylinders. And last, but certainly not least, all this excessive shaking affects the integrity of the coop construction, and requires more frequent coop repairs.

This shaking and some kind of dumping angle will cause the birds to lose their footing and slide against the coop doors, opening them up to allow the birds to exit the coop due to gravity.

An alternative is to keep the coop at the maximum angle, and to use some type of probe to move the birds out of the coop. This method is normally a last resort for the most stubborn birds, or those that are caught in the coop frame in some manner.

The faster the cradle dump cylinders operate, the greater the potential for machine-damaging shock to be operator-induced into the system. This shock can be in mid-stroke with the rapid valve handle reversal, or it can be at either end of the cylinder travel when the hydraulic cylinders reach the end of their stroke in either an up or down position.

The Direct Costs attributable to excessive cradle shaking:

• The cradle dump downtime costs can be horrendous when you consider that every bird in the plant has to pass through this piece of equipment.
• Catastrophic equipment failure can cause PERSONNEL INJURIES either at the time of failure, or during the required maintenance procedure to bring the equipment back on-line. Something as simple as a hydraulic hose failure can not only cause loss of hydraulic fluid, but it can also cause SERIOUS INJURY if all the hoses are not installed in a manner that offers line-of-sight hose protection for operating personnel.
• The failed hoses, cylinders, valves, and loss of hydraulic fluid are the least expensive items that can be itemized as an “excessive cradle dump shaking” cost.

We can prevent all this shock from occurring, while increasing the cradle dump angle to a suggested nominal angle of 55 degrees. Our No Shock Valve can be easily installed and adjusted to prevent any mid-stroke shock from happening, no matter how the operator moves his valve handle. Our Extended Cushion Hydraulic Cylinders will replace the existing cylinders and give you several advantages: In addition to having extra-long internal cushions, these cylinders have mounting hardware that is bolted on the cylinder and the cradle frame, so that any time the pivot point hardware starts to wear, all these pivot points can be replace without any cutting or welding.

This same No Shock Valve control system can be used anyplace that manual valve operation is causing shock in a hydraulic system, for dumpers or hanging belts. NEMA 4 standard or NEMA 4X stainless enclosures available.

We want to partner with the Poultry Industry to make the back dock machinery operate in a smooth, SAFE manner, and there is no good reason to accept excessive system shock as a normal operating procedure.