Tube support

A tube heater including structure forming a heating chamber having oppositely disposed side walls, a floor and a roof, said roof having a slot extending lengthwise thereof substantially midway between said side walls, burners to heat said chamber, a coil having vertically disposed convolutions located substantially midway between said side walls, a support having a vertically movable portion above said slot, one end of said coil extending through said slot and being fixedly attached to said movable portion, a bracket attached to the upper end of each convolution and extending through said slot, and movable means to support a convolution of the coil connected with each bracket whereby the coil is supported to move as a whole and with each convolution being able to move separately.