Abstract: A warming device is constructed to enclose barrels filled with lubricating oil for the purpose of maintaining the oil at operating viscosities even when ambient temperature conditions are severely cold. The barrel warming device includes a housing for supporting a plurality of barrels, a heating device placed on the housing for providing heat to the housing and the barrels, a movable hoist able to place or remove the barrels into or from the housing, and a skid which supports the housing and enables the easy transportation of the barrels. The barrel warming device has particular utility for storing various weights of lubricating oil needed by oil drilling rigs which are operated in cold climates.

Abstract: An indirect air heater having a single airflow path, the invention provides apparatus capable of discharging large volumes of heated air either toward outdoor work areas or into indoor spaces. The present heater is disposed outdoors, fresh air being taken into the heater and passed in heat exchanging contact with heated combustion products moving in a non-communicating flow within the heater. The heated fresh air is directed toward or into the space to be heated while the combustion products are vented to ambient.

Abstract: A metal fence post having an irregular polygon shape which is strong and resists bending and twisting better than posts made of the same gauge metal but of other construction. The method of making the fence post and the manner in which fence wires are tied thereto in order to construct an extra strong fence are included.