Enamel flow coating process and apparatus

A method of applying enamel slip to a heat exchanger coil comprising the steps of:

• mounting a heat exchanger coil on a rotatable shaft;
• while the heat exchanger coil is mounted to the rotatable shaft using a linear actuator to pivot the heat exchanger coil from a first position wherein the heat exchanger coil is not contained in an upwardly opening container of enamel slip, to a second position wherein the heat exchanger coil is substantially submerged in enamel slip contained in the upwardly opening container of the enamel slip to coat the heat exchanger coil with enamel slip;
• using the linear actuator to pivot the heat exchanger coil from the second position to a position where the heat exchanger coil is removed from the enamel slip and free to rotate on the rotatable shaft;
• driving the rotatable shaft and causing the heat exchanger coil mounted thereto to rotate;
• and
• continuing to rotate the heat exchanger coil until the coating slip coating the heat exchanger coil is no longer liquid;
• further comprising the step of while rotating the heat exchanger coil on the rotatable shaft, simultaneously rotating the heat exchanger coil about a second axis perpendicular to the rotatable shaft.

A method of applying a coating to the exterior of a heat exchanger coil of the type used in a hot water storage tank, comprising the steps of:

• mounting a heat exchanger coil in a first station to a clamp on a rotatable shaft mounted to a support bracket pivotally mounted on an arm forming a part of a wheel, the wheel being mounted for rotation about a horizontal axis on a frame;
• rotating the wheel about the horizontal axis to a second station which positions the heat exchanger coil above an upwardly opening tank mounted beneath the wheel, and locking the wheel against rotation;
• maintaining within the upwardly opening tank a quantity of enamel slip at a fixed level within the tank;
• stirring the quantity of enamel slip within the upwardly opening tank with a rotating paddle;
• operating an actuator arranged between the support bracket and the arm to pivot the support bracket, the rotatable shaft mounted to the support bracket, and the heat exchanger coil clamped to the rotatable shaft until the heat exchanger coil is substantially submerged in the enamel slip;
• operating the actuator until the heat exchanger coil is clear of the upwardly opening tank, followed by beginning rotating the heat exchanger coil on the rotatable shaft, and unlocking the wheel so it is free to rotate;
• rotating the wheel to a third station while collecting slip dripping from the heat exchanger coil with a drip guard which is positioned beneath the heat exchanger coil in the third station;
• and
• continuing to rotate the heat exchanger coil until a coating slip coating the heat exchanger coil is no longer liquid.

A method of applying a coating to the exterior of a heat exchanger coil of the type used in a hot water storage tank formed of a steel tube 1 to 3 inches in diameter having at least six complete coils, the heat exchanger coil having two open ends, the method comprising the steps of:

• mounting the heat exchanger coil to a clamp by the open ends on a rotatable shaft mounted to a support bracket pivotally mounted on an arm forming a part a wheel, the wheel being mounted for rotation about a horizontal axis on a frame;
• rotating the wheel about the horizontal axis to a position where the heat exchanger coil is above an upwardly opening tank mounted beneath the wheel;
• maintaining within the upwardly opening tank a quantity of enamel slip;
• extending a linear actuator arranged between the support bracket and the arm to pivot the support bracket, the rotatable shaft mounted to the bracket, and the heat exchanger coil clamped to the rotatable shaft, until the heat exchanger coil and the at least six complete coils are substantially submerged in the enamel slip;
• retracting the linear actuator until the heat exchanger coil is clear of the upwardly opening tank, followed by beginning rotating the heat exchanger coil on the rotatable shaft;
• rotating the wheel;
• and
• continuing to rotate the heat exchanger coil until a coating slip coating the heat exchanger coil is no longer liquid.