A 100-liter charge tank with legs and gusset weldment is a small welded pressure vessel used to buffer pump start-stop cycles in a water booster system: welded support legs hold it off the floor, and triangular gusset plates weld the legs to the tank shell for rigidity. TankSmith pairs VFD duplex control panels with CDL/CDLF booster pumps (0.37 kW to 200 kW) as a lower-maintenance alternative for Philippine commercial buildings.
What a Charge Tank With Legs and Gusset Weldment Actually Is
A charge tank, also called a hydropneumatic tank, surge tank, or pressure tank, is a small welded pressure vessel installed on the discharge side of a water booster pump. Its job is to hold a reserve of pressurized water and air so the pump does not switch on and off every time a tap opens, a cycle known as short-cycling that wears out motors and contactors faster than continuous duty. The '100L' in a spec sheet refers to the vessel's internal volume, about 100 liters, a size common on light commercial and residential booster setups. 'Legs' are the vertical steel supports welded to the underside of the tank shell so it can stand on a floor or slab instead of hanging on pipework. A 'gusset weldment' is the triangular gusset plate welded between each leg and the tank shell, reinforcing that joint against the bending load created by a full tank of water sitting several inches off the ground. This is shop-welded, single-shell fabrication, a different construction method from TankSmith's core product line: modular bolted panel tanks (FRP, GRP, HDG steel, or stainless steel 304/316) built in 1,000 liter to 500,000 liter capacities for bulk storage, not pressure buffering.
Why 100 Liters Is a Common Spec on Booster Pump Cut Sheets
A booster pump manufacturer sizes the charge tank against the pump's flow rate and the number of allowable starts per hour for the motor, not against building size. A 100-liter vessel is typical where the connected fixture count is small enough that a single small-to-mid pump handles demand without excessive cycling. TankSmith's own product range sits at a different point on the pressure side: CDL and CDLF series vertical multistage centrifugal pumps from 0.37 kW to 200 kW, built in SS304, sized to match a building's peak demand rather than one fixed tank size. On the storage side, TankSmith's modular panel tanks run from 1,000 liters up to 500,000 liters, covering the water reserve a building needs before it reaches the pump and charge tank stage. If a spec calls out a 100-liter charge tank with legs and gusset weldment, that component sits between the storage tank and the building's plumbing, and it is usually specified alongside the pump rather than sold as part of a bulk storage package. Buyers comparing quotes should confirm whether the charge tank is included with the pump package or priced separately, since it is a distinct fabrication from either the storage tank or the pump itself.
How VFD Duplex Control Reduces Reliance on a Large Charge Tank
TankSmith pairs its booster pumps with VFD duplex control panels built on Inovance variable frequency drives, rated IP54, with pressure feedback and auto-alternation between two pumps. A VFD ramps pump speed up and down to match real-time demand instead of switching a fixed-speed motor fully on or fully off. Because the pump modulates rather than cycling between two states, the system needs less stored pressure reserve to avoid short-cycling, which is the main reason a large charge tank exists in a fixed-speed setup. Pressure feedback lets the control panel hold outlet pressure within a tight band directly, and auto-alternation rotates duty between two pumps so no single unit runs continuously. This does not eliminate the need for a small pressure tank entirely, VFD systems still use one for drive stability at very low flow, but it changes the sizing conversation: a duplex VFD panel is a control-side answer to the same short-cycling problem a 100-liter charge tank with legs and gusset weldment is built to solve on a fixed-speed pump. Buyers weighing a welded charge tank against a VFD duplex panel should ask their supplier which approach fits their actual demand profile and duty cycle.
TankSmith's Turnkey Alternative: Tank, Pump, and Control Under One Contract
TankSmith is a Philippines-based turnkey installer: one team supplies, installs, and commissions both the storage tank and the pressure system under a single contract, so there is one point of accountability instead of a tank vendor and a pump contractor pointing at each other when something does not fit. The storage tanks are modular bolted panels in FRP, GRP/SMC, hot-dip galvanized steel, or stainless steel 304/316, built in capacities from 1,000 liters to 500,000 liters. Panels are WRAS-certified for potable water up to 65C, use NSF-compliant liners, come from an ISO 9001 certified partner factory, and are TUV SUD tested. TankSmith backs its FRP panels with a 3-year warranty and a 20 to 25 year design life. On the pressure side, CDL/CDLF vertical multistage centrifugal pumps (0.37 kW to 200 kW, SS304) pair with Inovance VFD duplex control panels for pressure feedback and auto-alternation. For a building that needs a small charge tank with legs and gusset weldment as part of a larger pressure system, TankSmith's turnkey scope covers the storage and pump side of that system so the mechanical and electrical work is coordinated from one supplier rather than split across separate purchase orders.
Who Specifies These Systems in the Philippines
In the Philippines, this kind of booster and storage setup, whether the pressure side uses a welded charge tank or a VFD duplex panel, shows up most often in commercial laundries sizing to kg/day linen throughput, hotels and resorts doing rooftop retrofits, hospitals and clinics that need redundancy and a code-compliant fire reserve, food manufacturing sites that require WRAS-compliant potable water, warehouses and manufacturing plants covering fire reserve and process water, and condominiums or high-rises retrofitting tight-access rooftops. TankSmith installs nationwide across NCR, Luzon, Visayas, and Mindanao, including PEZA and freeport zones such as SBMA, Clark, Cavite, and Batangas. Any of these facilities specifying a 100-liter charge tank with legs and gusset weldment on a mechanical drawing should confirm early whether the rest of the pressure system, pump, control panel, and storage tank, is being sourced from one supplier or several, since coordination gaps between separate vendors are a common cause of commissioning delays on this type of installation.
What to Verify Before You Buy a Charge Tank or Booster System
Before ordering a 100-liter charge tank with legs and gusset weldment, or the booster system around it, ask the supplier for the actual weld inspection records on the leg-to-shell gusset joints, since that connection carries the full load of a filled tank and is the most common failure point on welded pressure vessels. Ask what pressure rating and hydrostatic test the vessel carries, not just its volume. For the storage tank feeding that pressure system, confirm the panel material (FRP, GRP, HDG steel, or stainless steel), whether the panels carry WRAS certification for potable water and NSF-compliant liners, and whether the manufacturing partner holds ISO 9001 and TUV SUD test certification. Ask for the warranty term in writing: TankSmith backs its FRP panels with a 3-year warranty and a 20 to 25 year design life. Finally, confirm whether supply, installation, and commissioning are covered by one contract or split across a tank vendor, a pump vendor, and an electrical contractor, since split scopes are where responsibility for a failed weld or a mis-sized charge tank tends to get lost.
Frequently Asked Questions
A charge tank, also called a hydropneumatic or pressure tank, stores a reserve of pressurized water and air on the discharge side of a booster pump so the pump does not switch on and off every time a fixture opens. That on-off pattern, called short-cycling, wears out motors and contactors faster than steady operation. A 100-liter charge tank is a common size on light commercial and residential setups where a single small-to-mid pump covers demand. TankSmith's booster pumps (CDL/CDLF series, 0.37 kW to 200 kW) pair with VFD duplex control panels that modulate pump speed instead, which reduces how much reserve pressure the system needs from a tank of this kind.
The legs on a welded charge tank are vertical steel supports that let the vessel stand on a floor instead of hanging from pipework. A gusset weldment is the triangular gusset plate welded between each leg and the tank shell to reinforce that joint. A tank full of water sitting on legs puts a bending load on the leg-to-shell connection, and the gusset plate spreads that load over a wider weld area so the joint does not crack or fatigue over time. When comparing suppliers, ask for weld inspection records on the gusset joints specifically, since that connection is the most common failure point on this type of vessel.
No. A 100-liter charge tank with legs and gusset weldment is a small, single-shell, shop-welded pressure vessel used to buffer a booster pump's start-stop cycle. TankSmith's core product is different: modular bolted panel tanks in FRP, GRP, hot-dip galvanized steel, or stainless steel 304/316, built in capacities from 1,000 liters to 500,000 liters, used for bulk water storage rather than pressure buffering. The two sit in the same overall water system but solve different problems and are built with different methods, welded single-shell versus bolted modular panels.
TankSmith's stated product range covers modular bolted storage tanks (1,000 L to 500,000 L) and booster pump systems: CDL/CDLF vertical multistage centrifugal pumps (0.37 kW to 200 kW, SS304) with Inovance VFD duplex control panels for pressure feedback and auto-alternation. A small welded charge tank with legs and gusset weldment is typically specified and supplied alongside the pump package rather than as a TankSmith storage product. For a project that needs both the storage tank and the pressure system, TankSmith's turnkey scope covers supply, installation, and commissioning of the tank and pump side under one contract, which is worth asking about when the charge tank component is being quoted separately.
For the storage tank portion of a system, TankSmith's typical install window is 5 to 14 days for capacities from 20,000 liters to 500,000 liters, depending on tank size and how ready the civil works (foundation, platform) are on site. TankSmith installs nationwide, covering NCR, Luzon, Visayas, Mindanao, and PEZA or freeport zones such as SBMA, Clark, Cavite, and Batangas. Timelines for a smaller pressure system built around a 100-liter charge tank vary with the scope of mechanical and electrical work involved, so get a site-specific schedule before committing to a completion date.
For storage tank panels, check for WRAS certification (potable water use up to 65C), NSF-compliant liners, ISO 9001 certification at the manufacturing partner, and TUV SUD testing; TankSmith's panel systems carry all four. For a welded pressure vessel like a charge tank, ask for its pressure rating, hydrostatic test result, and weld inspection records on the leg-to-shell gusset joints specifically, since that connection carries the full load of a filled tank. Also confirm the warranty in writing: TankSmith backs its FRP panels with a 3-year warranty and a 20 to 25 year design life.
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