A boiler tube clamp including a first U-shaped midsection configured for pressing against one side of a boiler tube, a first hinge member arranged on one end of the first midsection, a threaded bolt hingedly attached to the other end of the first midsection, and a second U-shaped midsection configured for pressing against the other side of the boiler tube. The clamp further includes a second hinge member arranged on one end of the second midsection and hingedly connected to the first hinge member so that the first inner surface and the second inner surface close toward one another. A lip extends radially out from the second midsection and a jackscrew extends through the lip for adjusting the distance a boiler tube contained by the clamp extends into a boiler through a boiler header.