are available from these manufacturers:

Hydac Corp. (Hycon Div.)

	Bladder Accumulators The standard bladder accumulator consists of a "closed" rubber bladder inside a forged steel shell. A mechanically actuated valve closes when the fluid has been expelled, blocking off the fluid port, thereby enclosing the bladder within the shell. Where high discharge rates are required, a high flow model is available, using a larger diameter fluid port. Applications with corrosive environments may require shells furnished with an internal and/or external coating or manufactured from stainless steel. The top repairable accumulator permits service and maintenance of the bladder without removing the accumulator from the machine. When the pressure level of a system permits, a low pressure accumulator may be used. It is similar to a standard bladder accumulator, except that the poppet valve is replaced by a perforated plate covering the fluid port, and the shell may be of welded construction. For applications requiring light weight a Kevlar wrapped accumulator shell is available. The wrapping supports the thinner metal shell to permit a substantial weight reduction. Fluids are practically incompressible and cannot therfore store pressure energy. The compressibility of a gas (nitrogen) is utilized in hydro-pneumatic accumulators for storing fluids. HYDAC bladder accumulators are designed on this principle, using nitrogen as the compressible medium. The bladder accumulator consists of a fluid section and a gas section, with the bladder acting as a gas-proof screen. The fluid aroundt the bladder is connected with the hydraulic circuit, so that the bladder accumulator draws in fluid when the pressure increases thus compressing the gas. When the pressure drops, the compressed gas expands and forces the stored fluid into the circuit. HYDAC bladder accumulators consist of a welded or forged pressure vessel (shell), a bladder and ports for gas and fluid inlet. The gas and fluid sides are separated by the bladder. BLADDER MATERIALS Not all fluids are compatible with every elastomer at all temperatures. HYDAC offers the following choice of elastomers: - NBR (Standard Nitrile) - LT-NBR (Low Temperature Nitrile) - ECO (Epichlorohydrin) - IIR (Butyl) - EPR (Ethylene Propylene) - FPM (Fluorelastomer) CORROSION PROTECTION HYDAC offers internal and/or external protective coatings. If this is insufficient, stainless steel is also available. MOUNTING POSITION HYDAC bladder accumulators can be installed vertically, horizontally or even at an angle. When installing vertically or at an angle, the fluid port must be the bottom. On certain applications listed below, particular positions are preferable: - energy storage: vertical - pulsation damping: any position from horizontal to vertical - maintaining constant pressure: any position from horizontal to vertical - volume compensation: any position from horizontal to vertical SYSTEM MOUNTING HYDAC bladder accumulators are designed to be screwed or flanged directly onto the system. HYDAC also recommend the use of HYDAC's mounting components, refer to Mounting Components brochure #A3.502, to minimize the risk of failure due to system vibrations.

		Model SB 330/600 Standard Bladder Accumulator These accumulators come in two basic models. Model SB 330 has a 3000 PSI rating. Model SB 600 has a 5000 PSI rating. These are regular flow, bottom repairable accumulators. Also available are high flow, top repairable, and high flow, top repairable variations. There are 7 SB 330 sizes and 6 SB 600 sizes ranging from 1/4 to 15 nominal volume gallons. Line connections are threaded (BSP, Metric, SAE, or NPT) or flanged (SAE 2"-code 61 OR SAE 1-1/2"-code 62). Materials for the fluid port include: Synthetic coated carbon steel (internal/water service) Carbon steel Stainless steel (304) Stainless steel (316) Chemically plated carbon steel (water service) Low temperature carbon steel (< -40° F) Materials for the shell include: Synthetic coated carbon steel (internal/water service) Carbon steel Stainless steel (316) Low temperature carbon steel (< -40° F) Materials for the bladder compound include: NBR (Buna N) ECO (Hydrin) TIIR (Butyl) LT-NBR (low temperature Buna) FPM (Viton) Others Final pressure vessel codes vary depending on the country of installation. In the US and Canada pressure vessels are governed by the ASME pressure vessel code. HYDAC manufactures according to these standards. For installations in countries outside of the US, please consult Flo-Products Sales for appropriate certifications. Specifications and Options

		Model SB 800/1000 Special Bladder Accumulator These accumulators come in two models. Model SB 800 has a 11,600 PSI rating. Model SB 1000 has a 14,500 PSI rating. These special accumulators are available in either carbon steel or stainless steel shells in a 1.5 gallon size.

		Other Bladder Accumulator Low pressure bladder accumulators are available as well stainless steel bladder accumulators. Contact Flo-Products Sales for further information.

	Diaphragm Accumulators HYDAC diaphragm accumulators utilize the compressibility of a gas (nitrogen) in storing hydraulic energy. The gas is required because fluids are paratically incompressible and thus, can not store energy by themselves. The diaphragm is utilized to separate the gas and fluid sides of the accumulator. The diaphragm accumulator functions by drawing in fluid from the hydraulic circuit when the pressure increases and thus, compresses the gas. It returns this energy to the circuit as the pressure decreases by the expansion of the gas. A poppet is incorporated into the diaphragm to prevent its extrusion through the fluid port. HYDAC manufactures two types of diaphragm accumulators: - welded (non-repairable). - threaded (repairable). These have been successfully applied to both industrial and mobile applications in energy storage, maintaining pressure, leakage compensation and vehicle hydraulic systems (e.g., brake and suspension). CONSTRUCTION Welded TypeIt consists of: - an electronic beam welded shell with gas charging valve or altrnately, complete sealed. Fluid ports are available in various thread configurations. - a flexible diaphragm to separate the gas and fluid sides. - a poppet. Threaded Type It consists of: - a forged upper section with the gas valve. - a forged lower section with the fluid port. - a locking ring to fasten the upper and lower sections together. - a replaceable, flexible diaphragm to separate the gas and fluid sides. - a poppet. BLADDER MATERIALS Not all fluids are compatible with every elastomer at all temperatures. HYDAC offers the following choice of elastomers: - NBR (Standard Nitrile) - LT-NBR (Low Temperature Nitrile) - ECO (Epichlorohydrin) - IIR (Butyl) - FPM (Fluorelastomer) - others available upon request. CORROSION PROTECTION HYDAC offers internal and/or external protective coatings. If this is insufficient, stainless steel is also available. MOUNTING POSITION Diaphragm accumulators by design may be mounted in any position. In systems where contamination is a problem, HYDAC recommends a vertical mount with fluid port oriented downward. SYSTEM MOUNTING HYDAC diaphragm accumulators are designed to be screwed directly onto the system. HYDAC also recommend the use of HYDAC's mounting components, refer to Mounting Components brochure #A3.502, to minimize the risk of failure due to system vibrations.

		SBO Series Welded and Threaded Diaphragm Accumulators These accumulators come in four configurations. Configuration E1 (welded construction, rechargeable, Hydac gas valve version 1), and configuration E4 (welded construction, rechargeable, Hydac gas valve version 4) have a maximum allowable pressure ration of 8:1 or 4:1 and comes in six versions with fluid sizes ranging from 0.075 to 3.5 liters. Configuration E2 (welded construction, factory precharged and sealed, non-rechargeable) have a maximum allowable pressure ration of 8:1 or 4:1 and comes in four versions with fluid sizes ran < from 0.075 to 1 liter. Configuration A6 (threaded construction, rechargeable, Hydac gas valve version 1) has a maximum allowable pressure ration of 10:1 and comes in six versions with fluid sizes ranging from 0.1 to 2 liters. Connections thread is BSP, Metric, SAE, NPT Hexagonal or standard SAE connection. Materials for the fluid port include: Carbon steel Stainless steel (316) Chemically plated carbon steel (water service) Low temperature carbon steel (< -20° F) Materials for the shell include: Synthetic coated carbon steel (water service) Carbon steel Chemically plated carbon steel (water service) Stainless steel (316) Low temperature carbon steel (< -20° F) Materials for the bladder compound include: NBR (Buna N) ECO (Hydrin) IIR (Butyl) LT-NBR (low temperature Buna) FPM (Viton) Others Final pressure vessel codes vary depending on the country of installation. In the US and Canada pressure vessels are governed by the ASME pressure vessel code. HYDAC manufactures according to these standards. For installations in countries outside of the US, please consult Flo-Products Sales for appropriate certifications. Specifications and Options

	Piston Accumulators Fluids are practically incompressible and connot therefore store pressure energy. The compressibility of a gas (nitrogen) is utilized in hydro-pneumatic accumulators for storing fluids. HYDAC piston accumulators are designed on this principle, using nitrogen as the compressible medium. A piston accumulator consists of a fluid section and a gas section with the piston acting as a gas proof screen. The gas section is precharged with dry nitrogen gas. The fluid section is connected to the hydraulic circuit so that the piston accumulator draws in fluid when the pressure increases thus compressing the gas. When the pressure drops, the compressed gas expands and forces the stored fluid into the circuit. HYDAC piston accumulators consist of: a cylinder with a finely finished internal surface. an end cap on the gas side and the oil side, sealed with o-rings. lightweight metal piston. a variety of sealing systems are available depending on the application Three types of pistons for a variety of applications Type 1 - standard design for general accumulator operation without special requirements. Note:Piston friction must be taken into account for sizing purposes. Type 2 - low-friction design for higher piston speeds, slove movements without stick-slip effect and high number of actuations (millions). Note: Filtration ≤ 10µ absolute (ISO 16/13). Type 3 - general duty, cycle requirements 100,000's. SEALING SYSTEMS Precise information about the proposed operating conditions is required in order to select te most appropriate sealing system. Important criteria for this selection are: design pressure. effective pressure differential. number of actuations or cycles. temperature fluctuation. operating fluid. cleanliness of fluid. maintenance requirements. SEAL MATERIALS The following elastomers are available, depending on the operating conditions: NBR / acrylic nitrile butadiene rubber (trade name Perbunan) FKM / fluoro-rubber (trade name Viton) AU / polyurethane (trade name Vulkollan) Suitable materials are also available for low temperature applications. SYSTEM MOUNTING HYDAC piston accumulators operate in any position. Vertical instalation is preferable with the gas side up. ADVANTAGES OF HYDAC PISTON ACCUMULATORS: complete range from 1 quart to 100 gallons nominal volume. high ratios possible between precharge pressure and maximum working pressure. high flow rates - up to 4700 gpm from one accumulator. power savings. gas-proof and leak-free. no sudden discharge of gas when seal is worn. space efficient. piston location monitoring available. Further advantages of using the low-friction sealing system (Type 2 piston): minimum friction. suitable for low pressure differentials. no start-up friction, no stick-slip. low noise, no vibration. high piston speeds up to 12 fps continuous. improved accumulator efficiency. high life expectancy. low maintenance requirements. EFFECT OF SEAL FRICTION The permissible piston velocity depends on the sealing friction. Higher piston velocities are possible where there is less sealing friction. HYDAC piston accumulators with low friction seals allow continuous operating velocities of 12 fps with short excursions to 15 fps. Small pressure differentials between gas and oil side improve the effectiveness of HYDAC piston accumulators. The effect of the working pressure on the sealing friction is particularly striking in piston Type 1.

		SK Series Piston Accumulators These piston accumulators come in two basic models. Model SK 330 has a 3000 PSI rating. Model SK 600 has a 5000 PSI rating. There are 22 SK 330 sizes in three cylinder sizes and 16 SK 600 sizes in two cylinder sizes with capacities ranging from 2-1/2 to 80 nominal volume gallons. Line connection types on the fluid side are BSP, Metric, SAE, NPT, or flanged. Line connection types on the gas side are M28x1,5, 8V1 - ISO 4570, BSP, Metric, SAE, or flanged. Materials for the piston include: Choice of Seal Systems Seal System 1 Seal System 2 Seal System 3 Piston Material Type Aluminum Carbon steel Stainless steel (316) Carbon steel II Seal Compound Choices NBR (Buna N) LT-NBR (low temperature Buna) FPM (Viton) Others AU (Polyurethane) Materials for the shell include: End Cap Material Carbon steel Stainless steel (316) Low temperature carbon steel (< -20° F) Cylinder Material Carbon steel Stainless steel (316) Low temperature carbon steel (< -20° F) Seal Compound Choices NBR (Buna N) LT-NBR (low temperature Buna) FPM (Viton) Others AU (Polyurethane) Final pressure vessel codes vary depending on the country of installation. In the US and Canada pressure vessels are governed by the ASME pressure vessel code. HYDAC manufactures according to these standards. For installations in countries outside of the US, please consult Flo-Products Sales for appropriate certifications. There are five piston diameters ranging from 80 to 355 mm. Additional equipment available is three lengths of electrical end position control, extending position rod, and an ultrasonic system. Gas and fluid threaded connections come in five sizes depending on piston diameter. Gas and fluid flanged connections come in 17 variations depending on piston diameter. Flanged connections are not available for the smallest size piston (80mm) and only one variation is available for the 100mm piston. Specifications and Options