(Mafotokozedwe achidule) Kusamala kwa kukhazikitsa ndi kukonza ma valves a chitetezo: Kusamalira makina otetezeka: (1) valani ya chitetezo chokhazikika:
Khalidwe labwino kwambiri ndi labwino kwambiri, logwirizana ndi malongosoledwe a wogulitsa.it sichingayembekezere. Tikuyembekezera mgwirizano wotsatira.