The machines cannot be used for welding anything. The oxygen could. However your presumption that they'd rather make rockets, which they already seem to have an endless supply, rather than assist their ill, is based on propaganda. Whoever is ill, is someone's mother, father, brother, sister, wife, husband, child. Hamas and the militant factions are FROM the population, as a result of having their land usurped for 62 years. As for the UN transporting them.....source? BTW You do realize the UN is the delivery agent for ALL aid into "territories occupied".. so the story sounds rather.....strange to say the least.
Saudi policeman killed in Mecca after Islamic State raid (Reuters)
from the article: Report: Israel seizes oxygen machines donated to PA