There are many opportunities to protect your high pressure pump. The best pump protection is selecting the right pump for the application. The next best pump protection is proper installation. And the easiest pump protection is regular maintenance.
Selecting the correct high pressure pump for the application will offer the best pump protection. Trying to get a pump to do something for which it was not designed will inevitably cause problems, some more severe than others. Proper selection should include a review of the following factors: duty cycle; pump rating or specifications including flow and pressure limits; and the liquid to be pumped with consideration for temperature and chemical compatibility.
To offer maximum high pressure pump protection, the system duty cycle should be one of the primary considerations. If the job calls for 24 hour duty or heavy cycling, be certain the pump is designed for this heavy-duty performance and has a proven track record for minimum maintenance and long life under these conditions. This will avoid costly repairs and downtime.
If your application calls for frequent dormant cycles, select a pump that is easily cleaned or flushed. This can eliminate costly reactions to liquids left in the pump. Carefully reviewing the duty cycle can be a very important factor in protecting your high pressure pump.
Selecting a high pressure pump with a head construction that is compatible with the pumped liquid will provide greater protection for your pump and result in far less down time and service costs. Both the temperature and the chemical compatibility can affect the high pressure pump performance. The combination of chemicals and elevated temperatures can cause accelerated reactions within the pump and may require further upgrading of head and materials to assure maximum pump protection and reliability. Optional material for the seals and o-rings may be necessary to accommodate the elevated temperature or chemicals. Carefully review the pump construction to be certain the pump meets or exceed the chemical and temperature requirements. In high temperature situations the heat transfer to the drive-end may require additional consideration. Knowing the specifications of your application and matching them to the specifications of the high pressure pump will assure a proper selection. Pumps are typically tested and rated by the manufacturers' and should be operated well within the rated limits. Operation under extreme conditions such as maximum temperature, questionable liquids or heavy duty cycles or a combination of these factors may require that the pump be operated at less than its rated specifications such as lower RPM, lower pressure or an intermittent duty cycle for maximum pump protection.
The second best opportunity for protecting your high pressure pump is at installation. A careful review of the system layout and intended pump application should be done to assure the best system design and ultimate pump protection.
Primary consideration should be given to inlet conditions of the high pressure pump. Insufficient liquid, undersized inlet lines, excessive inlet suction or pressure, long feed lines, booster pumps or improper filtration can contribute to pump problems. Installing the appropriate safety measures will assure maximum pump protection. View Inlet Condition Check List before designing your high pressure pump system.
Many pumps function adequately with a supply tank and flooded inlet pressure. The supply tank should be sufficiently sized to provide enough liquid to the pump inlet [typically 6-10 times the system capacity]. The supply tank should have at least two baffles secured to the bottom of the tank to allow liquid to flow over the top and expel unwanted air bubbles. This baffled tank will minimize the aerated liquid being drawn into the pump. View Typical Reservoir Tank before designing your high pressure pump system.
Some local water supplies may provide pressures beyond the pump inlet pressure specifications and may require a pressure reducing valve to hold the inlet pressure within the pump limits. When booster pumps are used to feed the high pressure pump or long feed lines are necessary, a captive acceleration tube or C.A.T. may be necessary. The C.A.T. is a special type of inlet pulsation dampener that stabilizes the inlet pressure to the pump and assure a consistent inlet pressure to avoid the damage caused by liquid hammering and intermittent cavitation. The C.A.T. does not protect against starvation. View our Cavitation Check List for more information on cavitation. View more information on the C.A.T. before designing your high pressure pump system.
Suction feed is often the most difficult inlet condition and requires careful consideration to assure pump protection. Review the negative suction pressure limit for the pump and select a self-priming pump for best performance. Installing a check valve or foot valve to hold liquid in the inlet line may provide additional pump protection.
Proper inlet filtration is particularly significant in protecting your high pressure pump. Filters should be sized to meet or exceed the pump inlet line size to avoid any restrictions. Dual filters or larger capacity filters should be installed in heavily used systems to avoid clogged filters and starving the pump. Special consideration should be given to reclaim systems or liquids with known particulate to assure the proper filtration and best pump protection. Low flow shut-off switches should be installed to offer maximum pump protection against starvation.
Additional high pressure pump protection can be achieved with a careful review of the discharge line accessories. One of the least expensive accessories to assure pump protection is a pressure gauge. This device will monitor system pressure and give the first signal of changes and possible maintenance requirements.
Setting system pressure and offering pressure relief protection is a vital element in pump discharge protection. A regulator or unloader permits setting system pressure and handling unused pumped liquid. These valves will go into by-pass, if an obstruction occurs in the discharge line, thereby, avoiding damage to the pump. The type of valve selected will vary depending upon the type of application being performed, such as single gun, multiple nozzles or guns or hydrostatic testing. In high pressure pump systems a secondary relief valve is also recommended and should be set 200 PSI above the primary valve. Both the regulating and relief devices should exceed the flow and pressure rating of the pump to offer maximum pump protection.
More than one precaution is advisable for pump protection in high temperature systems. To avoid the high risk of cavitation, a pressurized inlet is recommended. Review Tech Bulletin 002 on Inlet pressure vs Liquid Temperature for more information. Installing a thermal relief valve to bleed-off system high temperature liquid from the by-pass line or a temperature control device to shut-off the system at pre-set temperatures will offer the necessary pump protection and avoid costly repairs or permanent pump damage. View Typical Installations before designing your high pressure system.
The best pump protection is a thorough, regularly scheduled maintenance. View Preventative Maintenance Check List for guidelines in establishing your service schedule. Learn about your pump through training seminars or data sheets and service manuals provided by the manufacturer before operation. Most pump manufacturers offer guidelines for typical servicing, however, each installation offers variants and an individualized schedule should be adopted. Change the pump drive-end oil regularly using the manufacturers' recommended oil. Service the seals and valves on a regular schedule. Do not wait until the pump is leaking or quits running to do service. Use genuine original manufacturers' service parts to assure optimum performance.
Working with a systems specialist will help identify potential system problems. Following these system guidelines will help maximize your high pressure pump protection.